ZNAK SAGITE — više od fantastike — edicija, časopis, knjižara...

Potrebna mi je pomoć za jedan projekat na kojem radim. To jest, da mi neko ko se bolje od mene razume u pozitivističke nauke objasni nekoliko stvari i odgovori na nekoliko pitanja. Unapred zahvalan za svu pomoć:

1) Ako je neka planeta četiri ili pet puta veća od Zemlje, pod kojim uslovima na njoj mogu da vladaju približno isti uslovi za život kao na Zemlji, sa približnom gravitacijom i da li je pri tom moguće da godina i dan na njoj budu približnog trajanja kao na Zemlji?

2) Da li je moguće da planeta ima dva meseca koji oko nje kruže a da se pri tom jedan od ta dva meseca ne vidi sa površine planete?

3) Da bi ti meseci kružili oko rečene planete X za isto vreme kao Zemljin mesec oko nje, da li moraju da budu već od Zemljinog meseca?

Preciziraj ovo prvo. Četiri ili pet puta veći prečnik? Ili površinu? Ili zapreminu? Npr. planeta duplo većeg prečnika bi imala oko 4 puta veću površinu, a oko 8 puta veću zapreminu.

E sad, ja sam matematičar (i to bez diplome) a ne fizičar, pa je moguće da ovo što pišem i nije tačno. Po mojoj računici, da bi planeta duplo većeg prečnika imala istu gravitaciju, morala bi imati 4 puta veću masu. Ali imala bi i 8 puta veću zapreminu, što znaći da bi morala imati 2 puta manju gustinu. Dakle, takva planeta bi morala biti napravljena od laganijeg materijala ili bi morala imati podosta šupljina.

Quote from: Ygg on 28-08-2010, 17:08:24
Preciziraj ovo prvo. Četiri ili pet puta veći prečnik? Ili površinu? Ili zapreminu? Npr. planeta duplo većeg prečnika bi imala oko 4 puta veću površinu, a oko 8 puta veću zapreminu.

E sad, ja sam matematičar (i to bez diplome) a ne fizičar, pa je moguće da ovo što pišem i nije tačno. Po mojoj računici, da bi planeta duplo većeg prečnika imala istu gravitaciju, morala bi imati 4 puta veću masu. Ali imala bi i 8 puta veću zapreminu, što znaći da bi morala imati 2 puta manju gustinu. Dakle, takva planeta bi morala biti napravljena od laganijeg materijala ili bi morala imati podosta šupljina.

Potrebno mi je da planeta ima veću površinu, što valjda znači i veći prečnik? A podosta šupljina mi sasvim odgovara. A šta je sa trajanjem dana i godine? Da li veličina sunca tu igra neku ulogu?

Ово питање ме враћа 25 година уназад. На неком Сферакону у Загребу присутнима је готово идентично питање поставио Горан Худец, тада један од перспективних младих СФ писаца у Хрватској. Било му је потребно за неку причу коју је замислио. Тада сам му одговорио да седне, пише и не објашњава.
Ево и Ygg је дао прави одговор: да, под одређеним условима све је могуће. Ако ће се исповртети добра прича.

2. Misliš na to da je jedan od ta dva meseca zaklonjen iza ovog drugog?

Quote from: Nightflier on 28-08-2010, 17:14:42
Potrebno mi je da planeta ima veću površinu, što valjda znači i veći prečnik? A podosta šupljina mi sasvim odgovara. A šta je sa trajanjem dana i godine? Da li veličina sunca tu igra neku ulogu?

To sa trajanjem dana i godine nemam pojma ovako napamet. Morao bih konsultovati kakav udžbenik fizike.

Nego, pomislio sam da bi problem mogla predstavljati i atmosfera, tj. prevelik atmosferski pritisak. Ali kad sam malo razmislio čini mi se da i ne bi. Ako bi vazdušni omotač bio iste debljine kao i na Zemlji (oko 200 km), onda bi i atmosferski pritisak trebao biti isti (jer je ista gravitacija).

Quote from: scallop on 28-08-2010, 17:22:35
Ово питање ме враћа 25 година уназад. На неком Сферакону у Загребу присутнима је готово идентично питање поставио Горан Худец, тада један од перспективних младих СФ писаца у Хрватској. Било му је потребно за неку причу коју је замислио. Тада сам му одговорио да седне, пише и не објашњава.
Ево и Ygg је дао прави одговор: да, под одређеним условима све је могуће. Ако ће се исповртети добра прича.

Znao sam da ćeš da se javiš sa tim odgovorom, samo što u ovom slučaju ja ne pišem priču i potrebno mi je da znam koji su ti uslovi pod kojima je to što sam pitao moguće.

Quote from: Potopljeni on 28-08-2010, 17:23:23
2. Misliš na to da je jedan od ta dva meseca zaklonjen iza ovog drugog?

To je jedna varijanta. Valjda. Zapravo, nije bitno čak ni da to bude mesec u opipljivom smislu. Sad ću malo da lupam, kao u Star Treku, ali neko čudo koje ima svoju gravitacionu silu kojom kao mesec utiče na planetu. Mini crna rupa? Čak bi i više odgovaralo da nije nešto opipljivo...

Треба ти већи Балкан да га праведније поделиш? Или те звао Горан Худец? Томе који те је то питао дај мој одговор, сасвим је у реду. И, где си ти данас? Ако смо се договорили?

Quote from: Ygg on 28-08-2010, 17:30:26

Quote from: Nightflier on 28-08-2010, 17:14:42
Potrebno mi je da planeta ima veću površinu, što valjda znači i veći prečnik? A podosta šupljina mi sasvim odgovara. A šta je sa trajanjem dana i godine? Da li veličina sunca tu igra neku ulogu?

To sa trajanjem dana i godine nemam pojma ovako napamet. Morao bih konsultovati kakav udžbenik fizike.

Nego, pomislio sam da bi problem mogla predstavljati i atmosfera, tj. prevelik atmosferski pritisak. Ali kad sam malo razmislio čini mi se da i ne bi. Ako bi vazdušni omotač bio iste debljine kao i na Zemlji (oko 200 km), onda bi i atmosferski pritisak trebao biti isti (jer je ista gravitacija).

Pa da. Vazdušni pritisak valjda rešava gravitacija.

Mini crna rupa ti nije dobra, jer joj je vreme trajanja veoma kratka.

2. astrolozi tvrde da Zemlja ima 2 mjeseca i da se jedan ne vidi. Pročešljaj po netu, ali mislim da je drugi znatno manji i da ga zovu Lilit ili Lilith, dobio ime po prvoj Adamovoj ženi. On je u astrologiji tzv mračni mjesec.

sjećam se da sam ranije čitao u nekoj astrološkoj knjizi da je nelogično da naša galaksija ima 9 planeta i da po astrološkim ''računanjima'' mora imati bar još jednu. I onda su prije par godina isprevrnuli sunčev sistem i pronašli baš svašta (koliko uopšte ima planeta danas?) da sam se prenerazio zbog te glupe knjige, i opet se ne sjećam naziva...

tu sam pročitao i za drugi mjesec.

mislim, astrologija, SF, valjda ti je od neke pomoći

Osim toga, uvek se može "izmisliti" neka nova čestica ili "mesec" sastavljen od štatijaznam: gravito-antiprotonskih čestica, nevidljiva u spektru u kom ljudi vide. A kad već pominješ ST - imaš i opciju "cloak", pa možda i neku vrstu prirodnog načina skrivanja. Ili stanovnici jednostavno nisu u stanju da vide mesec zbog toga što je vidljiv u spektru za koji stanovnici planete nemaju odgovarajuće receptore (ko zna kako i da li uopšte i vide).

     I neki astronomi tvrde da Zemlja ima dva meseca (drugi se takođe naziva Lilit), međutim mala je verovatnoća da na današnjem stupnju razvoja astronomije, još uvek ostaje eluzivan. Osim toga astronomski Lilit bi trebao biti vidljiv prilikom prolaska ispred Sunca (a neki tvrde i da su ga tako i videli). Takođe, ako i postoji, stvara zanemarljivu gravitacionu silu.
     Pretpostavljam, međutim, da ti treba nešto što stvara veću gravitacionu silu od podosta udaljenog i od Meseca mnogo manjeg satelita kao što je hipotetični Lilit.

Znam za astrološki mesec, ali ovde su pravila igre takva da planeta mora biti zasnovana na nauci.

pa i Potopljeni ti kaže da i astronomi razmatraju mogućnost postojanja drugog mjeseca, doduše, Lilit je u najboljem slučaju nešto prečnika 10-20 metara



u naučnom smislu možeš se poigravati samo pitanjem percepcije stanovnika planete

to ti je albedo 0 - mjera refleksije jednog tijela. Ako je albedo 0 onda tijelo uopšte ne reflektuje svjetlost, ne odbija sunčeve zrake i ne može se vidjeti

npr asfalt ima 0.04 albedo i to je slaba, skoro nikakva refleksija

dakle neki mjesec od asfalta ili slične materije :lol:

Gravitacija planete je g=G*m/r^2, što će reći da ako planeta ima istu gravitaciju kao Zemlja, a poluprečnik 5 puta veći onda masa treba da joj bude 25 puta veća nego Zemljina. Relativna gustina treba da bude manja u odnosu na Zemljinu, jer je masa proporcionalna kubu poluprečnika (r^3). Više litijuma, a manje gvožđa, i tu smo negde.

Perioda orbite (vreme okretanja oko sunca) je T= 2*PI*sqrt(r^3/(M+m)), gde je r udaljenost od zvezde, M je masa zvezde, m je masa planete. Masa naše planete je 25 puta veća od mase Zemlje, ali to je i dalje zanemarljivo u odnosu na masu zvezde, tako da planeta može da bude na istoj udaljenosti kao Zemlja od Sunca, a i zvezda da bude mase Sunca, i godina će opet isto trajati.

Trajanje dana je nezavisno od svega ostalog, te naša planeta može slobodno da ima isto trajanje dana kao i Zemlja.

Mesec može da se slabo vidi ako je jako mali i jako daleko, ima neočekivanu (iskošenu) putanju, i jako mali albedo, i ako je recimo atmosfera planete takva da se raspršuje i ono malo svetlosti što se odbija od tamnog meseca.

Veličina satelita ne igra ulogu u računanju orbite, ali masa igra, međutim masa ima malu ulogu ako je zanemarljiva u odnosu na masu planete (vidi jednačinu iz drugog pasusa). Ako želiš da OBA satelita imaju periodu kao naš Mesec onda je to zamislivo ako je ovaj skriveni satelit u jednoj od Lagranžovih tačaka, http://en.wikipedia.org/wiki/Lagrangian_point (http://en.wikipedia.org/wiki/Lagrangian_point) a ako je recimo u tački L2 na slici onda će biti i nevidljiv sa planete, jer će biti iza glavnog satelita.

Quote from: mac on 28-08-2010, 21:20:24
Gravitacija planete je g=G*m/r^2, što će reći da ako planeta ima istu gravitaciju kao Zemlja, a poluprečnik 5 puta veći onda masa treba da joj bude 25 puta veća nego Zemljina. Relativna gustina treba da bude manja u odnosu na Zemljinu, jer je masa proporcionalna kubu poluprečnika (r^3). Više litijuma, a manje gvožđa, i tu smo negde.

Perioda orbite (vreme okretanja oko sunca) je T= 2*PI*sqrt(r^3/(M+m)), gde je r udaljenost od zvezde, M je masa zvezde, m je masa planete. Masa naše planete je 25 puta veća od mase Zemlje, ali to je i dalje zanemarljivo u odnosu na masu zvezde, tako da planeta može da bude na istoj udaljenosti kao Zemlja od Sunca, a i zvezda da bude mase Sunca, i godina će opet isto trajati.

Trajanje dana je nezavisno od svega ostalog, te naša planeta može slobodno da ima isto trajanje dana kao i Zemlja.

Mesec može da se slabo vidi ako je jako mali i jako daleko, ima neočekivanu (iskošenu) putanju, i jako mali albedo, i ako je recimo atmosfera planete takva da se raspršuje i ono malo svetlosti što se odbija od tamnog meseca.

Veličina satelita ne igra ulogu u računanju orbite, ali masa igra, međutim masa ima malu ulogu ako je zanemarljiva u odnosu na masu planete (vidi jednačinu iz drugog pasusa). Ako želiš da OBA satelita imaju periodu kao naš Mesec onda je to zamislivo ako je ovaj skriveni satelit u jednoj od Lagranžovih tačaka, http://en.wikipedia.org/wiki/Lagrangian_point (http://en.wikipedia.org/wiki/Lagrangian_point) a ako je recimo u tački L2 na slici onda će biti i nevidljiv sa planete, jer će biti iza glavnog satelita.

Mek, ako mi uspe projekat, navešću te u zahvalnici kao tehničkog savetnika! Mnogo ti hvala! Mogu li da te cimam za još neke stvari? Na primer, ako nam je dan na planeti sa tolikom masom približno isti kao na Zemlji, da li to znači da je njena rotacija oko svoje ose brža? Da li to znači da su olujni vetrovi snažniji?

Dodatni komentar. Lagranžove tačke L1, L2, i L3 su nestabilne. Tu mogu da orbitiraju samo veštački sateliti, koji mogu da koriguju svoju orbitu, a pasivno telo će neminovno jednom napustiti ove ekvilibrijume. Zato su tačke L4 i L5 su stabilne. Jedno vreme je postojala ideja da se na tim tačkama instaliraju orbitalne stanice, ali ideja je napuštena u korist ideje kolonizacije Meseca. http://en.wikipedia.org/wiki/L5_Society (http://en.wikipedia.org/wiki/L5_Society)

Teorijski, u vezi s "tamnim mesecom" - ako je reč o malom nebeskom telu, ali sačinjenom od recimo plutonijuma ili nekog sličnog elementa velike težine, da li bi moglo da bude nevidljivo i da vrši uticaj na površinu planete, kao što vrši "primarni" mesec?

Quote from: Nightflier on 28-08-2010, 21:38:27Mek, ako mi uspe projekat, navešću te u zahvalnici kao tehničkog savetnika! Mnogo ti hvala! Mogu li da te cimam za još neke stvari? Na primer, ako nam je dan na planeti sa tolikom masom približno isti kao na Zemlji, da li to znači da je njena rotacija oko svoje ose brža? Da li to znači da su olujni vetrovi snažniji?

Pazi, ove informacije vučem iz osnovnoškolskog malog mozga, uz teško oslanjanje na Vikipediju. Dok smo u elementarnim vodama biće lako, ali sad kad se povede pitanje vanzemaljske meteorologije tu već možemo da padnemo na neku glupost, pa da nam se smeju ljudi od nauke. Uostalom, nek se smeju, ko ih šiša.

Elem, da nastavimo. Pošto kažemo da dan traje kao dan na Zemlji onda je ugaona brzina ista (stepen u sekundi), ali je brzina tačke na površini veća (metar u sekundi), jer je poluprečnik veći. Koliko to utiče na vetrove? Nemam pojma, ali pošto na vetrove utiče i gustina atmosfere i solarna radijacija i isijavanje toplote s površine (a na to utiče i biosfera planete) onda možemo da pretpostavimo da ostali činioci mogu da anuliraju Koriolisov efekat, ili šta je već to zbog čega bi oluje bile veće. Ako je cela planeta u džungli onda će oluje verovatno biti manje nego da je sve kamen i voda.

Quote from: mac on 28-08-2010, 21:53:36

Quote from: Nightflier on 28-08-2010, 21:38:27Mek, ako mi uspe projekat, navešću te u zahvalnici kao tehničkog savetnika! Mnogo ti hvala! Mogu li da te cimam za još neke stvari? Na primer, ako nam je dan na planeti sa tolikom masom približno isti kao na Zemlji, da li to znači da je njena rotacija oko svoje ose brža? Da li to znači da su olujni vetrovi snažniji?

Pazi, ove informacije vučem iz osnovnoškolskog malog mozga, uz teško oslanjanje na Vikipediju. Dok smo u elementarnim vodama biće lako, ali sad kad se povede pitanje vanzemaljske meteorologije tu već možemo da padnemo na neku glupost, pa da nam se smeju ljudi od nauke. Uostalom, nek se smeju, ko ih šiša.

Elem, da nastavimo. Pošto kažemo da dan traje kao dan na Zemlji onda je ugaona brzina ista (stepen u sekundi), ali je brzina tačke na površini veća (metar u sekundi), jer je poluprečnik veći. Koliko to utiče na vetrove? Nemam pojma, ali pošto na vetrove utiče i gustina atmosfere i solarna radijacija i isijavanje toplote s površine (a na to utiče i biosfera planete) onda možemo da pretpostavimo da ostali činioci mogu da anuliraju Koriolisov efekat, ili šta je već to zbog čega bi oluje bile veće. Ako je cela planeta u džungli onda će oluje verovatno biti manje nego da je sve kamen i voda.

Pa, pretpostavimo da na tolikoj planeti postoji čitav niz klimatskih zona, kao na Zemlji. Neke od njih su verovatno nenastanjive, kao kod nas polovi, dok su neke verovatno pravi mali rajevi. To je već manje bitno. Kao što kažeš, atmosfera je već manji problem od ovoga ostalog. Mislim da ću sa ovim obrazloženjima proći na naredni nivo konkursa.

Sad, ne znam koji ću zadatak tada dobiti, ali verovatno će imati veze sa biosferom.

Quote from: Nightflier on 28-08-2010, 21:46:37
Teorijski, u vezi s "tamnim mesecom" - ako je reč o malom nebeskom telu, ali sačinjenom od recimo plutonijuma ili nekog sličnog elementa velike težine, da li bi moglo da bude nevidljivo i da vrši uticaj na površinu planete, kao što vrši "primarni" mesec?

Gustina Meseca je 3.3464 g/cm^3, a gustina plutonijuma 19.84 g/cm^3. Da bi satelit bio mase Meseca a gustine plutonijuma morao bi da ima poluprečnik (3.3464 / 19.84)^(1/3) (treći koren odnosa gustina) = 0.553 poluprečnika Meseca, iliti pola poluprečnika. Čak i da je sav od plutonijuma bio bi vidljiv, i tu sad imamo problem. Crna rupa mase Meseca je recimo skoro nevidljiva, i relativno stabilna, ali takvi objekti su ređi od jednoroga. http://www.einstein-online.info/elementary/quantum/evaporating_bh (http://www.einstein-online.info/elementary/quantum/evaporating_bh)

Quote from: mac on 28-08-2010, 22:24:58

Quote from: Nightflier on 28-08-2010, 21:46:37
Teorijski, u vezi s "tamnim mesecom" - ako je reč o malom nebeskom telu, ali sačinjenom od recimo plutonijuma ili nekog sličnog elementa velike težine, da li bi moglo da bude nevidljivo i da vrši uticaj na površinu planete, kao što vrši "primarni" mesec?

Gustina Meseca je 3.3464 g/cm^3, a gustina plutonijuma 19.84 g/cm^3. Da bi satelit bio mase Meseca a gustine plutonijuma morao bi da ima poluprečnik (3.3464 / 19.84)^(1/3) (treći koren odnosa gustina) = 0.553 poluprečnika Meseca, iliti pola poluprečnika. Čak i da je sav od plutonijuma bio bi vidljiv, i tu sad imamo problem. Crna rupa mase Meseca je recimo skoro nevidljiva, i relativno stabilna, ali takvi objekti su ređi od jednoroga. http://www.einstein-online.info/elementary/quantum/evaporating_bh (http://www.einstein-online.info/elementary/quantum/evaporating_bh)

Koliko vidim, teorijski može da postoji. Ali, da li bi ta mini crna rupa svojim gravitacionim poljem nekako destabilizovala mesec? Verovatno ne bi, ako je na dovoljnoj udaljenosti od njega? Recimo, u fiksnom položaju u odnosu na mesec, pa da se zajedno sa njim rotira oko planete?

Računa se samo masa. Ako je telo mase Meseca onda nema veze što je crna rupa. Biće prosto minijaturna, i horizont događaja će biti mali. U Lagranžovim tačkama L4 i L5 neće destabilizovati glavni satelit, a i ako je na drugoj orbiti takođe neće destabilizovati (kao što ni svi Jupiterovi sateliti ne destabilizuju jedan drugog). Ali ja lično nisam za objašnjenje sa crnom rupom, to je prosto suviše egzotično. Više ima smisla da je recimo planeta uvek u oblacima (kao Sarakš), ili da recimo to telo izaziva neki efekat u atmosferi tako da samo sebe skriva od običnog pogleda (a stanovnici to doživljavaju kao neki redovni putujući oblak, ili auroru, ili šta već).

Ajd sad da ja malo lupam. Ima li smisla da ta planeta ima dva mjeseca iste veličine i na istoj udaljenosti, ali da se uvijek nalaze na dijametralno suprotnim tačkama u odnosu na planetu? Znači, kruže po istoj orbiti istom brzinom, pa su uvijek nasuprot jedan drugom. Pošto je planeta pet puta većeg prečnika od Zemljinog, valjda se ni sa jedne tačke na planeti ne bi vidjela obadva mjeseca istovremeno. Stanovnici te planete bi viđali naizmjenično jedan pa drugi mjesec ali bi ako bi ti mjeseci bili dovoljno slični oni bi mogli misliti da je to jedan te isti mjesec. To bi im ujedno dalo utisak da je planeta manja nego što jeste, jer mjesecu ne treba puno vremena da je obiđe.

Quote from: Ygg on 29-08-2010, 14:16:44
Ajd sad da ja malo lupam. Ima li smisla da ta planeta ima dva mjeseca iste veličine i na istoj udaljenosti, ali da se uvijek nalaze na dijametralno suprotnim tačkama u odnosu na planetu? Znači, kruže po istoj orbiti istom brzinom, pa su uvijek nasuprot jedan drugom. Pošto je planeta pet puta većeg prečnika od Zemljinog, valjda se ni sa jedne tačke na planeti ne bi vidjela obadva mjeseca istovremeno. Stanovnici te planete bi viđali naizmjenično jedan pa drugi mjesec ali bi ako bi ti mjeseci bili dovoljno slični oni bi mogli misliti da je to jedan te isti mjesec. To bi im ujedno dalo utisak da je planeta manja nego što jeste, jer mjesecu ne treba puno vremena da je obiđe.

Zanimljiva ti je ideja, samo što bi to promenilo neke druge stvari u projektu. Ja sam čak predložio da planeta ima više od dva messeca - recimo devet - ali odbili su me ostali učesnici u projektu.

Cilj je, zapravo, da se osmisli planeta istovremeno slična i različita od zemlje. Fora je da se sličnosti i različitosti što više usklade. Tako sam dao predlog da planeta bude veća od Zemlje, ali da na njoj vlada približno ista sila gravitacije, da ima dva meseca, ali da se jedan ne vidi - i tako dalje.

Sad, tvoj predlog mi je dao ideju, samo ne znam koliko je realna. Naime, šta ako planeta X ima satelit koji kruži oko nje u velikoj elipsi, tako da je vidljiv samo jednom u sto ili dvesta ili hiljadu godina? Da li je tako nešto izvodljivo?

Pluton (koji više nije planeta) ima iskošenu i izduženu orbitu od 248 godina, ali oko Sunca. Objekat veličine Plutona, pa i veći bi mogao da ima još ekscentričniju orbitu, ali oko zvezde, a ne i oko planete. Mislim da ne može planeta da ima periodu od godinu dana, a da satelit te planete ima periodu od sto godina. Pokušavam da nađem na internetu nešto što bi moglo da objasni takav sistem, ali možda će mi za to trebati dve-tri godine.

Quote from: mac on 29-08-2010, 15:37:51
Pluton (koji više nije planeta) ima iskošenu i izduženu orbitu od 248 godina, ali oko Sunca. Objekat veličine Plutona, pa i veći bi mogao da ima još ekscentričniju orbitu, ali oko zvezde, a ne i oko planete. Mislim da ne može planeta da ima periodu od godinu dana, a da satelit te planete ima periodu od sto godina. Pokušavam da nađem na internetu nešto što bi moglo da objasni takav sistem, ali možda će mi za to trebati dve-tri godine.

A planetoid koji kruži oko sunca sa takvom orbitom da jednom u nekoliko stotina godina seče orbitu planete X tako da sa nje bude vidljiv kao mesec?

Quote from: mac on 29-08-2010, 15:37:51
Pokušavam da nađem na internetu nešto što bi moglo da objasni takav sistem, ali možda će mi za to trebati dve-tri godine.

xrofl

Quote from: Nightflier on 29-08-2010, 15:46:02A planetoid koji kruži oko sunca sa takvom orbitom da jednom u nekoliko stotina godina seče orbitu planete X tako da sa nje bude vidljiv kao mesec?

Ček sad, jel treba da bude vidljiv ili nevidljiv? Na stranu to, ako se planetoid toliko približi da bude prividno veličine Meseca onda će ga planeta skrenuti sa njegove putanje, to jest ako mu je perioda orbite i bila 100 godina, ko zna šta će mu biti posle susreta. Takvi opasni susreti su ekstremno retki, jer kad se jednom i dese manji objekat bude izbačen iz orbite, i uglavnom završi na planeti, ili u zvezdi, ili u Kujperovom pojasu. Ako objekat ne mora da bude prividne veličine Meseca onda je to sasvim ostvarivo, zapravo evo ti Halajeve komete za primer.

Na žalost, što duže budemo razgovarali biće sve manje prilika da ja kažem "to je teorijski moguće" (uglavnom zbog mog ograničenog znanja). Možda je bolje da poslušaš Scallopa :-)

Quote
A planetoid koji kruži oko sunca sa takvom orbitom da jednom u nekoliko stotina godina seče orbitu planete X tako da sa nje bude vidljiv kao mesec?

Ovo je možda i moguće... možda čak i jednom u više stotina godina (da ne kažem hiljadu)... ali onda se postavlja pitanje karakteristika planete X, da li u tom sistemu postoje i druge planete, njihov raspored, veličina, itd... bilo šta što može da utiče na kretanje planetoida...
(mada, ili mora prići jako blizu da se vidi kao Mesec ili mora biti dovoljno velik. U oba slučaja, velika je verovatnoća da ih međusobni gravitacioni uticaji dovedu na putanje sa neizbežnim sudarom dva objekta. Ne tvrdim da je nemoguće ali je verovatnoća za postojanjem takvog sistema (a da je stabilan) - veoma mali)

Druga stvar je stepen razvoja stanovnika planete, jer ako su dostigli do "galilejevske fizike", mogu i sa jednostavnim teleskopom slučajno (naravno ovo je samo mogućnost, slučajni pronalazak takvog planetoida bi bio malo verovatan) naći planetoid, a ako su stigli do "njutonovske fizike", mogu i bez direktnog opažanja skontati da postoji ta planeta (naravno, samo u slučaju da je njen gravitacioni uticaj na druge planete sistema dovoljno veliki)...

Ostali učesnici u projektu definitivno su se zagrejali za ideju velike planete sa jednim mesecom i "anomalijom" tipa crne rupe skrivenom negde iza meseca. Dopala im se analogija sa astrološkim "tamnim mesecom", a i dopalo im se što je to toliko retka pojava da postoji samo teoretski. Misle da će to naš projekat učiniti dovoljno zanimljivim da prođemo u drugu fazu.

Mnogo hvala svima. Ako prođem u drugu fazu, opet ću potražiti savete. :)

Auf... Mislim da telo može da orbitira u L2 samo ako je zanemarljive mase u odnosu glavni satelit. A čak i tada mora veštački da se održava u toj orbiti, inače ispada. Ali dobro, ako je vama lepo i meni je.

Ima jedan asteroid, Cruithne (http://en.wikipedia.org/wiki/3753_Cruithne), koji trenutno orbitira u širokom luku oko L4, i gledano sa Zemlje ima otvorenu orbitu u obliku bubrega. Ovo otvorena znači da je na kraju svakog "bubrežnog" ciklusa malo dalje od Zemlje nego na početku.

Gravitacija planete zavisi od MASE, a ne od njene veličine; dakle, ako je veća, mora da bude PRAZNIJA. Zemlja ima gustinu valjda 5.5 kg po kubnom metru. Sve to može da se izračuna sa vrlo malo matematike. Ali ovako odokativno, da bi objekat duplo veći u prečniku bio iste mase, treba da bude tri puta manje specifične težine...

Recimo to možeš da rešiš na sledeći način, fizički je to slabo verovatan ishod, al ko zna... dakle planeta je pet ili koliko god puta veća od Zemlje ali PRAZNA, nema užareno jezgro, već samo ljušturu debljine npr. 1000 kilometara. Ali onda nemaš vulkane, niti tektonska pomeranja.

Quote from: Boban on 04-09-2010, 12:32:20
Gravitacija planete zavisi od MASE, a ne od njene veličine; dakle, ako je veća, mora da bude PRAZNIJA. Zemlja ima gustinu valjda 5.5 kg po kubnom metru. Sve to može da se izračuna sa vrlo malo matematike. Ali ovako odokativno, da bi objekat duplo veći u prečniku bio iste mase, treba da bude tri puta manje specifične težine...

Recimo to možeš da rešiš na sledeći način, fizički je to slabo verovatan ishod, al ko zna... dakle planeta je pet ili koliko god puta veća od Zemlje ali PRAZNA, nema užareno jezgro, već samo ljušturu debljine npr. 1000 kilometara. Ali onda nemaš vulkane, niti tektonska pomeranja.

Dao sam predlog da kora planete bude nešto deblja nego što je kod zemlje - ali šupljikava. To jest, da obiluje pećinskim sistemima mnogo više nego što je to slučaj kod Zemlje. Projekat je odaslan, pa ću videti da li će proći. U svakom slučaju, bila mi je zanimljiva glavolomka.

Hmm, kubik vode teži jednu tonu, pa pretpostavljam da kubik zemlje ne može da bude lakši.

Pa, ne bi trebalo da je lakši. Plus, ne znam baš u kojoj meri pećinski sistemi zaista mogu da utiču na gustinu planete, baš kao što nisam sigurna ni koliko je izvodljivo imati planet kao striktno ljušturu bez jezgra... to je meni baš žešće u domenu fikcije, iako totalno nisam frik po tim pitanjima, naprotiv... Ali po pitanju meseca, bar  ovako kako je ovde postavljeno, čini mi se da gore pominjane anomalije naprosto ne bi bile dovoljno stabilne pa ni trajne, pa bi zato tu funkciju daleko bolje vršili relativno poznatiji objekti, znači uglavnom nekakvi gravitacijom 'uhvaćeni' fragmenti asteroida. A da bi takvi sateliti bili nevidljivi ili tek slabo/povremeno vidljivi, trebalo bi da imaju orbite pod određenim uglom u odnosu na planetin ekvator, što je sasvim okej premisa za nasumično uhvaćene objekte, ali to opet znači da oni ne bi ni bili 'meseci' u smislu u kom mi definišemo naš Mesec, nego prosto sateliti sa prozvoljnim orbitama u odnosu na planetu, pa zato i vidljivi tek povremeno. Fiksni sateliti, sa pravilnijim kružnim orbitama, bi bili vidljivi čak i ako su među najtamnijim objektima sunčevog sistema, kao c-tip asteroid, recimo; primera radi, Marsovi meseci reflektuju tek 6% sunčeve svetlosti, što je manje refleksije nego što je ima ugalj, a pri tom su po gustini tek dvaput jači od vode i upola slabiji od samog Marsa, pa kontam da su svejedno vidljivi sa površine, plus to što je u pitanj ustvarno zanemarljiva plimna vuča, ali su svejedno oba satelita okrenuta ka Marsu uvek istom stranom, a to daje dovoljno prostora za razne pretpostavke.  

Treba uzeti u obzir da je Zemljina kora nekoliko stotina kilometara, a ostatak je užarena polugasovita, poluplazmatična masa male težine. Dakle, kora utiče sa tek nekim delom promila u ukupnoj masi.
Hoću da kažem, da šupljikavost kore ne rešava ništa; potrebna je praznina unutar većine planete.

Kora ima manju gustoću od plašta, zato i pliva na njemu. Neka te ne zavara to što je plašt tekući, ima on veću gustoću od kore.

Što se tiče samih pitanja, ako želiš imalo realizma, zaboravi na šupalj planet. Jedna mogućnost da bude veći, a iste gravitacije, je da se brzo rotira. Doduše, onda je efektivna gravitacija jednaka Zemljinoj, a što ideš dalje prema polovima, to je gravitacija jača.

Tehničke karakteristike:

1. ako je gustoća materijala ista, ako planet ima dvostruki radijus, gravitacija na površini je dvostruko veća (ako je triput veći, gravitacija je triput veća itd.)

2. Malo sam se igrao s Excelom. Ako želiš imati planet koji je
2
3
4 ili
5
puta veći od Zemlje, da bi na ekvatoru efektivna gravitacija bila jednaka Zemljinoj, on se na ekvatoru mora okretati realnom brzinom:
22
38
54
70
puta brže od Zemlje, odnosno dan na njemu će trajati:
0,09
0,08
0,07
0,07

Zemljinog dana.

Doduše, rekao si da želiš da dan traje isto kao na Zemlji, dakle ne znam zašto sam ovo uopće računao, ali bilo je zabavno pa nema veze.

Što se tiče "mjeseca koji se ne vidi", ako želiš ikakvu realnost, zaboravi na to. Odgovor na 2. pitanje je: "Ne". Točka. Osim ako su na planetu stalno oblaci, ali onda se ni prvi mjesec ne vidi.

Što se tiče kruženja oko sunca, tu masa planeta ne igra NIKAKVU ulogu. Brzina/vrijeme kruženja ovise isključivo o masi sunca i udaljenosti od sunca. Točka. Potpuno je svejedno je li riječ o PEZ bombonu ili Jupiteru Sve dok ta masa ne počne ometati samo sunce, ali to ovdje vjerojatno nije slučaj).

Doduše, možda je riječ o paralelnom svemiru u kojemu je gravitacijska konstanta drugačija. Onda imaš razne opcije vezane i uz gravitaciju i veličinu planeta i uz mjesec i uz sve ostalo, ali za to moraš znati brojke. Ako ne znaš, zaboravi.

Ne, reč je o našem svemiru sa našim fizičkim zakonima. Ali, svejedno, projekat nije prošao dalje, tako da je sve ovo bila samo zabavna igrica. Hvala vam svima.

Quote from: Izitpajn on 10-09-2010, 16:13:13
Kora ima manju gustoću od plašta, zato i pliva na njemu. Neka te ne zavara to što je plašt tekući, ima on veću gustoću od kore.

Bez obzira da li je ovo tačno ili ne, gravitacija ne zavisi od veličine, nego od mase i udaljenosti od centra.
Elem, masa Meseca je 81x manja od mase Zemlje, ali mu je prećnik 4 puta manji, pa je teža 6x manja.

U suštini, ako bi planeta bila pet puta veća od Zemlje, a imala dva puta manju gustinu, otprilike bi gravitacija bila ista.
Znam da ti to više ne treba, ali zapravo uopšte nije ni trebalo da se smarate sa matematikom i astrofizikom; jednostavno, tako je kako odaberete i kraj.

Quote from: Nightflier on 10-09-2010, 16:53:53
Ne, reč je o našem svemiru sa našim fizičkim zakonima. Ali, svejedno, projekat nije prošao dalje, tako da je sve ovo bila samo zabavna igrica. Hvala vam svima.

Увек тако бива кад слушаш математичаре.  :lol:

Quote from: scallop on 10-09-2010, 19:39:46

Увек тако бива кад слушаш математичаре.  :lol:

:cry: :cry: :cry:

Sad bi bar moglo da padne više detalja o tom konkursu, ili šta li je već bio. I malo konkretnije o vašoj ideji.

Quote from: Boban on 10-09-2010, 18:07:14U suštini, ako bi planeta bila pet puta veća od Zemlje, a imala dva puta manju gustinu, otprilike bi gravitacija bila ista.

Gravitacija  bi bila 2,5 puta veća ;)

ti si u zabludi, jer gravitacija opada sa udaljenošću od jezgra.
Sedi i ispiši brojeve pa ćeš videti.

Pa eto, to za planetu bez jezgre... meni se učinilo da je prilično riskantno izvlačiti kojekakve grandiozne koncepte bez dobre astrofizičke potkovanosti. A ne vidim ni bog zna kakvu potrebu za time, kad za ove navedene potrebe ima sasvim dovoljno dokumentovanih fenomena na koje svaki laik može sasvim zdravo da se osloni...

Quote from: Boban on 12-09-2010, 02:24:08
ti si u zabludi, jer gravitacija opada sa udaljenošću od jezgra

Ma da?

Doduše, ja sam računao da "pet puta veće" znači "pet puta veći radijus", ali sam se kasnije sjetio da si možda mislio "pet puta veći volumen". Ako je tako, onda je u redu.

Dakle, molim njegovati preciznost izričaja. Fizika nije za amatere.

Pa ako u formuli za određivanje gravitacije figurira poluprečnik na kvadrat; nikako ne može biti linearna veza. Drugim rečima, ista masa, duplo veći prečnik znači četiri puta manju gravitaciju.

Problem s gravitacijom je u tome što se ona ravnomerno (prema formuli) distribuše u prostoru, tj. nema pravolinijski smer, a masa ne mora da bude pravilno raspoređena u prostoru. Neki tvrde da je masa Meseca neravnomerno raspoređena i da je njegova gravitacija različita na različitim mestima. Zbog toga su u početku spuštanja na Mesec bila neuspela, jer je računata slabija gravitacija, a izgleda da je bila znatno veća od 1/6 Zemljine.

Takođe, treba znati da gravitacija koja pripada "masi" postoji i izvan te mase (kao dejstvo), u okolnom prostoru, pa se to dejstvo sabira i dobija se "tačka težišta" koja može da bude i u praznom prostoru.

Dakle, dovodi se u sumnju tvrdnja da je gravitacija osobina mase - može da bude i nešto drugo u pitanju. Videćemo da li će da nađu tu Božansku Bozu ovi u Cernu, pošto očigledno nisu sigurni šta je zapravo "izvor" gravitacije.

http://peswiki.com/index.php/PowerPedia:Tesla%27s_Dynamic_Theory_of_Gravity (http://peswiki.com/index.php/PowerPedia:Tesla%27s_Dynamic_Theory_of_Gravity)

Ovaj tip je dosta spekulisao i dokazivao, ali ja nisam stručan da bih mogao da mu u potpunosti verujem. Međutim, dosta je zanimljivo to što priča.

Quote from: Boban on 12-09-2010, 17:21:56
Pa ako u formuli za određivanje gravitacije figurira poluprečnik na kvadrat; nikako ne može biti linearna veza. Drugim rečima, ista masa, duplo veći prečnik znači četiri puta manju gravitaciju.

...i osam puta manju gustoću. Dakle, da Zemlju raztegneš na dupli promjer bez dodavanja mase, mogla bi plutati na vodi.

Nego, o čemu mi ovdje uopće raspravljamo?

ali gustina nema nikakve veze sa masom, zapravo ima matematički u određivanju kolika je masa, ali već određena masa daje određenu gravitaciju na određenoj udaljenosti od centra mase. U svakom slučaju dolazimo do šupljeg nebeskog tela za početni zahtev.

Masa Jupitera je 317.8 Zemljinih masa, ali gravitacija na površini ekvatora (mada ne znam šta im to znači "površina" na Jupiteru) je svega 2.528 g.

Gustina mu je skoro pet puta manja od Zemljine.

http://www.newscientist.com/article/mg21028154.200-when-the-multiverse-and-manyworlds-collide.html?full=true (http://www.newscientist.com/article/mg21028154.200-when-the-multiverse-and-manyworlds-collide.html?full=true)

QuoteCosmologists reconcile this seeming contradiction by assuming that the superposition eventually "collapses" to a single state. But they tend to ignore the problem of how or why such a collapse might occur, says cosmologist Raphael Bousso at the University of California, Berkeley. "We've no right to assume that it collapses. We've been lying to ourselves about this," he says.

Dosta je bilo PRETPOSTAVKI. Da li su se ti naučnici konačno osvestili????

Dosta s lagarijama...  xfuck5

Ceo tekst.

http://arxiv.org/PS_cache/arxiv/pdf/1105/1105.3796v1.pdf (http://arxiv.org/PS_cache/arxiv/pdf/1105/1105.3796v1.pdf)

Ne samo što su Srbi sada stvarno narod najstariji u Europi (ili bar imaju najstarije stanovništvo), nego astronomi sad tvrde i da je naš svemir toliko star da je skoro potpuno prestao da proizvodi nove zvezde:

Study: The Universe Has Almost Stopped Making New Stars (http://www.wired.com/wiredscience/2012/11/universe-making-stars/) 

Quote
By Ian Steadman, Wired UK
Most of the stars that will ever exist have already been born, according to the most comprehensive survey of the age of the night sky.


An international team of astronomers used three telescopes — the UK Infrared Telescope (http://www.jach.hawaii.edu/UKIRT/) and the Subaru Telescope (http://www.naoj.org/index.html), both in Hawaii, and Chile's Very Large Telescope (http://www.eso.org/public/teles-instr/vlt.html) — to study trends in star formation, from the earliest days of the universe. Extrapolating their findings has revealed that half of all the stars that have ever existed were created between 9 and 11 billion years ago, with the other half created in the years since. That means that rate at which new stars are born has dropped off massively, to the extent that (if this trend continues) 95 percent of all the stars that this universe will ever see have already been born.

Several studies have looked at specific time "epochs", but the different methods used by each study has restricted the ability to compare their findings and discern a fuller model of how stars have evolved over the course of the entire universe's lifespan.

We do know that many stars around today — including our own — likely formed out of the dust left over from earlier, bigger stars going supernova in the early years of the universe. The problem was figuring out exactly how many stars the universe used to give birth to relative to how many are born in later years, as it seemed that at some point there was a steep drop off in the creation of new stars.
The telescopes searched for alpha particles emitted by Hydrogen atoms (commonly found in star formation, appearing as a bright red light) throughout huge patches of sky. Snapshots were taken of the look of the universe at defined different points in time, when it was 2, 4, 6 and 9 billion years old — a sample that's 10 times as large as any previous similar study.
The results showed clearly that half of all the stars that have ever existed in the universe were created more than 9 billion years ago, with the remaining half coming into existence since then. On the Subaru Telescope's site (http://www.naoj.org/Pressrelease/2012/11/05/index.html), the study's lead author, Leiden University's David Sobral (http://home.strw.leidenuniv.nl/~sobral/SOBRAL/Welcome.html), writes: "The production of stars in the Universe as a whole has been continuously declining over the last 11 billion years; it is 30 times lower today than at its likely peak 11 billion years ago. If this trend continues, no more than five percent more stars will exist in the Universe. We are clearly living in a Universe dominated by old stars. All of the action in the Universe occurred billions of years ago!"
Importantly, it also provides a way to reconcile the previously confusing disparity between the number of stars we can observe and the number of stars we know should have been created by the universe. The first generations of stars would have been extremely large — many hundreds of times larger than our Sun — and would have burned through their fuel quickly, undergoing supernovae death and providing the scattered discs of dust that later stars and planetary systems will have formed out of.
The findings map onto this, showing a huge rate of star formation which slowed rapidly after the first generation 9 billion years ago. It then took almost five times as much time for the same number of stars to be born again, accounting for the second half of all observed star formation. Findings from other studies into star formation — which used smaller sample sizes, or different methods — also fit onto the graph that the team derived, reinforcing the "huge early peak then rapid decline" theory. The study has been published in the Monthly Notices of the Royal Astronomical Society, and is available to read here (http://arxiv.org/pdf/1202.3436v2.pdf).
Unfortunately, then, it looks like our universe is running out of steam — in only a few more billion years, the study predicts, we may well be seeing the very last star that will ever be born. That's if humans manage to survive that long, of course.

Nema veze, pravićemo mi veštačke zvezde.

...od blata.

Za jedne blato, za druge materijal za fuziju :)

Sad pokušavam da se setim u kojoj beše priči ili romanu detoniraju bombu u srcu Jupitera, da bi od njega napravili zvezdu...

druga Odiseja?

Није било бомбе у "Другој одисеји", већ монолити заврше посао. И настане Луцифер.

znam, nego kontam da je možda NF mislio na to. nema veze...

Updated model for identifying habitable zones around stars puts Earth on the edge (http://www.gizmag.com/habitable-zone/26051/)

Quote
Researchers at Penn state have developed a new method for calculating the habitable zone around stars. The computer model based on new greenhouse gas databases provides a tool to better estimate which extrasolar planets with sufficient atmospheric pressure might be able to maintain liquid water on their surface. The new model indicates that some of the nearly 300 possible Earth-like planets previously identified might be too close to their stars to to be habitable.
So far, scientists have found some 18,000 extrasolar planet candidates with only a handful of these the right size, distance and having the proper orbital characteristics to be potentially habitable. "Habitable" is very broadly defined as being very approximately the right size and having a temperature where liquid water could exist on the surface of the planet. It's a very generous definition, but it's still one that leaves a very large margin of error.
Part of the reason is the variables the scientists use to calculate the habitable zone. One half of the equation is the star itself. Is it old? Is it young? Is it hot? Is it cool? Is it a variable? These determine how far the habitable zone is from the star and how wide it is. Then there is the planet itself, with characteristics such as size and temperature used to fine tune the estimates.
The Penn State model is based on previous work by James Kasting, Evan Pugh Professor of Geosciences also at Penn State. In the current study, the habitable zone is calculated based on stellar flux incident on a planet, that is, the amount of light falling on it, instead of its equilibrium temperature.
It is not, however, a way of coming up with a simple temperature reading. Instead, it's a complex computer model based on assumptions about the atmosphere of the planet and how it absorbs and radiates heat under given conditions. Even though these calculations are so involved they need a supercomputer to carry them out, they are still very simplified compared to reality and operate on a number of assumptions. For example, this study assumes a one-dimensional, radiative-convective (http://en.wikipedia.org/wiki/Climate_model#Radiative-convective_models), cloud-free climate. The team themselves admit that some factors may have been under or overestimated and the results will reflect this.
The team used updated absorption databases of greenhouse gases, such as carbon dioxide and water vapor, that are more accurate than those used by Kasting 20 years ago. These were fed into supercomputers at Penn State and the University of Washington and from this the habitable zone was calculated for various classes of stars.
The habitable zone was calculated between the point where the planet would be so hot that water would be hopelessly lost (the inner limit) and the point where the greenhouse effect would be too weak to melt ice (the outer limit). The results of the Penn State study indicate that the habitable zones are farther away from their stars than previously thought. This means that some extoplanets previously thought to be potentially habitable might not be so.
One disturbing finding of the study was that the Solar System's habitable zone lies between 0.99 AU (92 million mi, 148 million km) and 1.70 AU (158 million mi, 254 million km) from the Sun. Since the Earth orbits the Sun at an average distance of one AU, this puts us at the very edge of the habitable zone.
This may seem like a good argument for moving to Mars, which has an average distance from the Sun of 1.52 AU, but the team is careful to point out that their model doesn't take into account feedback from clouds, which reflect radiation away from the Earth and stabilize the climate.
According to the team, the model can be used to investigate the over 2,000 potential systems found by the NASA Kepler mission (http://www.gizmag.com/tag/kepler-mission/). It could also help the Penn States Habitable Zone Planet Finder (a spectrograph designed to seek water-sustaining planets) as well as NASA's proposed Terrestrial Planet Finder telescope network.
A paper describing the team's results has been accepted for publication in the Astrophysical Journal (http://iopscience.iop.org/0004-637X), but a pre-publication copy is available for viewing (http://arxiv.org/abs/1301.6674) (PDF).
Source: Penn State (http://live.psu.edu/story/63930)

Prvo sam pomislio da bi ovo više pasovalo u "Gde bi trebalo poslati SF ekspedicije", a onda sam ustanovio da taj topik baš i ne ide u DELA STRANIH AUTORA. Na kraju, ispostavilo se da se još nekoliko topika na forumu bavi istom ili sličnom materijom u odeljku NAUKA I KVAZINAUKA. Bože, kakav haos na ovom forumu!

 
(https://www.znaksagite.com/diskusije/proxy.php?request=http%3A%2F%2Fimages3.kurir-info.rs%2Fslika-620x333%2Fotkrice-srpski-fizicari-foto-sukiipbacrs-1362994547-280337.jpg&hash=e6944bdbc5e7cd9ff3935f7d3ef6faa2bbb38a13)

BEOGRAD - Srpski naučnici Milovan Šuvakov i Veljko Dmitrašinović, sa Univerziteta u Beogradu uspeli su da pronađu nova rešenja apstraktne naučne zagonetke koja je naučnike noćima držala budnim - može li se predviteti kako će tri objekta orbitirati jedan oko drugog na periodičan način.

U prvih 300 godina otkako je "problem tri tela" definisan, samo su tri familije rešenja otkrivene. Nedavno, dva domaća fizičara su otkrila još 13 novih familija. Ovo je pravi podvig u matematičkoj fizici koji bi mogao da značajno pomogne astrofizičarima da razumeju nove planetarne sisteme.

Otkriće ovih novih rešenja ostavilo je naučnike širom sveta zapanjenima i oduševljenim.

"Obožavam ovakve stvari", kaže Robert Vanderbei, matematičar sa Univerziteta Prinston koji nije bio umešan u rad na ovom projektu. On dodaje da je proveo celu noć razmišljajući o ovim rezultatima.

Problem tri tela potiče iz 1680. ih godina. Isak Njutn je već uveliko pokazao da njegov novi zakon gravitacije uvek može da predvidi orbite dva tela u gravitacionom polju – kao što je sistem koji se sastoji od zvezde i planete – sa apsolutnom preciznošću. Orbite u ovom slučaju su uvek elipse. Međutim, Njutn nije bio u stanju da dođe do sličnih rešenja za slučaj u kom tri tela orbitiraju jedna oko drugih. Dva veka su naučnici isprobavali različite pristupe, sve dok nemački matematičar Hajnrik Bruns nije ukazao da je potraga za opštim rešenjem problema tri tela uzaludna i da su samo specijalni slučajevi mogući za rešavanje. U opštem slučaju, poznato je da je kretanje tri tela neponavljajuće.

Ipak, specijalne, periodične slučajeve bilo je teško pronaći. Slavni matematičari Lagranž i Ojler su pronašli neka od rešenja u XVIII veku, ali novih otkrića na ovu temu nije bilo sve do sedamdesetih godina XX veka i razvoja modernog računarstva, kada su američki matematičar Rodžer Bruk i francuski astronom Mihel Enon uspeli da otkriju još. Do sada, specijalni slučajevi su bili podeljeni u tri familije: Lagranž-Ojlerova familija, Bruk-Enonova familija i familija oblika osmice, od kojih je poslednja otkrivena 1993. godine od strane fizičara Kristofera Mura sa Instituta Santa Fe.

Familija oblika osmice se zove tako zato što opisuje tri tela koja prate jedno drugo po orbitama u obliku broja osam. Lagranž-Ojlerova rešenja su jednostavnija i predstavljaju tri tela podjednako udaljena jedna od drugih koja se kreću po kružnici – poput vrteške. Bruk-Enonova familija je najsloženija: dve tela se kreću napred i nazad unutra dok treće telo orbitira okolo spolja.

Otkriće čak 13 novih familija, zaslugama fizičara Milovana Šuvakova i Veljka Dmitrašinovića sa Univerziteta u Beogradu, čini da sada ukupan broj familija specijalnih slučajeva problema tri tela iznosi 16.

"Rezultati su prelepi i prelepo su predstavljeni", kaže Ričard Montgomeri, matemaričar na Univerzitetu Kalifornije, Santa Kruz, koji nije bio umešan u otkriće.

Pronalaženje bilo kog od rešenja ima zastrašujuće nepovoljne izglede. Tri tela u prostoru se mogu postaviti na bezbroj načina. Nekako, treba pronaći početne uslove (početne pozicije i brzine) koji bi nakon određenog vremena doveli ova tela ponovo u te iste pozicije sa istim uslovima, kako bi cela ova "igra" mogla da se ponovlja u nedogled. Na osnovu rada koji je objavljen u časopisu Fizikal rivju leters, metod Šuvakova i Dmitrašinovića podrazumeva da se započne sa postojećim rešenjem u računarskoj simulaciji, a onda da se štimuju početni uslovi sve dok se ne dobije novi tip orbite.

"Ono što smo uradili je najjednostavnija stvar koju bi iko zamislio", kaže Dmitrašinović.

"Bili smo šokirani kada smo došli do novih rešenja, a bili smo još više šokirani kada smo saznali da sve ovo nije bilo prethodno otkriveno."

Suočeni sa impozantnim brojem novih rešenja, beogradski fizičari su uveli i novi klasifikacioni sistem. Oni su upotrebili apstraktni prostor nazvan "sfera oblika" koji opisuje oblik orbita pomoću međusobnih udaljenosti objekata. Tri tačke na ekvatoru sfere koje označavaju gde bi se dva tela sudarila, zajedno sa zatvorenom linijom na sferi koja ne prolazi kroz pomenute tačke, mapiraju koliko tela mogu da se približe jedna drugom. Najjednostavnije rešenje na sferi oblika je iz Lagranž-Ojlerove familije. To je samo jedna tačka, što u stvarnom prostoru predstavlja tri tela koja održavaju konstantnu i jednaku međusobnu udaljenost dok orbitiraju po kružnici.

Druga rešenja su mnogo intrigantnija. Jedno od novih rešenja, nazvano "predivo", izgleda kao klupko na sferi oblika, dok orbite ovog rešenja u stvarnom prostoru izgledaju još složenije – kao velika hrpa špageta. Sva ova rešenja mogu se pogledati OVDE.

Šuvakov i Dmitrašinović su podelili sve orbite, uključujući i prethodno poznate, u 16 familija na osnovu figura koje formiraju na sferi oblika. Ove familije su sortirali u četiri klase na osnovu simetrije i drugih karakteristika oblika, gde prva klasa sadrži sva prethodno otkrivena rešenja.

Sledeći korak beogradskih fizičara je da vide koliko je od njihovih novih rešenja stabilno – koliko će rešenja ostati na orbiti i u slučaju malih perturbacija. Ako su neka od rešenja stabilna, to znači da postoji dobra šansa da se pronađu i u stvarnosti. Trenutno, jedino opšteprihvaćeno rešenje problema tri tela posmatrano u svemiru je sistem koji čine Sunce, Jupiter i jedan od obližnjih asteroida iz grupe Trojanaca, koji orbitiraju u stilu Lagranž-Ojlerove kružnice. No, ukoliko budemo posmatrali dovoljno egzoplanetarnih sistema, postoji verovatnoća da ćemo videti neka nova, kompleksnija rešenja takođe – poput Sunčevog sistema koje izgleda kao hrpa špageta.

"Posmatračka astronomija se razvija jako ubrzano", ističe Dmitrašinović, ali i dodaje da će detektovanje nekog od ovih rešenja u svemiru još neko vreme biti vrlo teško.
Kurir (http://www.kurir-info.rs/bum-u-fizici-neverovatno-otkrice-srpskih-naucnika-clanak-689249)         

Zanimljivo. I ova nova klasifikacija im je dobra.

Ovaj Šuvakov će sad možda morati da malo uozbilji svoj sajt, http://suki.ipb.ac.rs/ (http://suki.ipb.ac.rs/)

Quote from: mac on 11-03-2013, 12:38:05
http://suki.ipb.ac.rs/ (http://suki.ipb.ac.rs/)

znači, 2Up3R

Ne znam gde drugo ovo da stavim. Nil deGras Tajson je poklonio svoju naučničku pažnju filmu Gravitacija, jer film to zaslužuje. Prvo je gledao film i oduševio se. Onda je na Tviteru naveo neke netačnosti u filmu (http://www.huffingtonpost.com/2013/10/07/gravity-accuracy_n_4057280.html). Mediji su reagovali kako eto NDGT ocrnjuje film, pa je morao čovek da reaguje navodeći i neke detalje koji su verno prikazani (http://www.theverge.com/2013/10/10/4823078/neil-degrasse-tyson-gravity-movie-high-quality). Na primer orbite teleskopa Habl i Međunarodne svemirske stanice su devedesetak minuta, kao što se i potencira u filmu.

E sad, šta je problem? Svemirski krš koji urniše sve na svom putu takođe orbitira (i uništava) u periodi od tih 90 minuta, ali se kreće u suprotnom smeru od svega ostalog u filmu. Posledica? Krš i sve ostalo u filmu će se sretati na svakih 45 minuta, a ne 90 kao što film prikazuje. Neko treba da javi Tajsonu, da ne živi čovek u neznanju...

Nastanjiva zona je proširena novim modelom. Procenjeni broj planeta u našoj galaksiji koje mogu da podrže život povećao se za nekih 1,5 milijardi. Takođe, dobili smo više vremena na Zemlji pre nego što Sunce postane prevruće za tečnu vodu (temperatura vremenom raste na zvezdama).

http://www.space.com/23921-habitable-zone-exoplanets-sunlike-stars.html (http://www.space.com/23921-habitable-zone-exoplanets-sunlike-stars.html)
http://www.popularmechanics.com/science/space/deep/the-goldilocks-zone-for-planets-is-growing-16256444 (http://www.popularmechanics.com/science/space/deep/the-goldilocks-zone-for-planets-is-growing-16256444)

Is Earth Weighed Down By Dark Matter? (http://slashdot.org/topic/datacenter/is-earth-weighed-down-by-dark-matter-or-internet/)

Quote
Earth may have a dark-matter corset weighing it down... or that might just be a shadow.

There may be a giant ring of dark matter invisibly encircling the Earth, increasing its mass and pulling much harder on orbiting satellites than anything invisible should pull, according to preliminary research from a scientist specializing the physics of GPS signaling and satellite engineering.

The dark-matter belt around the Earth could represent the beginning of a radically new understanding of how dark matter works and how it affects the human universe, or it could be something perfectly valid but less exciting despite having been written up by New Scientist and spreading to the rest of the geek universe on the basis of a single oral presentation of preliminary research at a meeting of the American Geophysical Union in December.

The presentation came from telecom- and GPS satellite expert Ben Harris, an assistant professor of mechanical and aerospace engineering at the University of Texas- Arlington, who based his conclusion on nine months' worth of data that could indicate Earth's gravity was pulling harder on its ring of geostationary GPS satellites than the accepted mass of the Earth would normally allow.

Since planets can't gain weight over the holidays, Harris' conclusion was that something else was adding to the mass and gravitational power of Earth – something that would have to be pretty massive but almost completely undetectable, which would sound crazy if predominant theories about the composition of the universe didn't assume 80 percent of it was made up of invisible dark matter.

Harris calculated that the increase in gravity could have come from dark matter, but would have had to be an unexpectedly thick collection of it – one ringing the earth in a band 120 miles thick and 45,000 miles wide.

Harris, (http://www.uta.edu/mae/index.php?page=faculty/benharris.php) an expert in Global Positioning Systems, GPS networks, spacecraft systems engineering and founder of the open-source GPS software project GPS ToolKit (http://www.gpstk.org/bin/view/Documentation/WebHome), wasn't looking for dark matter specifically, but was trying to explain observations that suggested the Juno space probe NASA launched in August  (http://www.newscientist.com/article/dn20765-waterscouting-probe-to-take-off-for-jupiter.html)seemed to be going faster than it should have while taking a loop around the Earth to pick up a little speed for its trip to Jupiter.

The probe's unexpected extra bit of speed, other researchers suggested, could have been caused by something different about Earth's gravity, though what that could have been wasn't clear.

One possibility was that the 1964 calculation by the venerable International Astronomical Union (http://www.iau.org/) underestimated the Earth's mass –and therefore its gravitational pull – causing NASA scientists to underestimate the speed the Juno probe would build up running "downhill" into Earth's gravity well during its final fly-by.

In an analysis published in 2009, Institute for Advanced Study researcher Stephen Adler  (http://prd.aps.org/abstract/PRD/v79/i2/e023505)suggested the reason for the anomaly could have been that the density of dark matter within the Solar System – and around the Earth in particular – could be much higher than astrophysicists had assumed.

Dark matter – invisible and so-far almost undetectable – was invented to try to explain why the universe does seem to be expanding from a single point as Big Bang theory predicts, but not nearly as fast as it should.

Galaxies, stars and other matter should only crawl away from each other at current speeds if there were a lot more gravity holding them back than there would be if the matter we could see were all the matter in the universe. Making the math work – getting it to agree with what the universe had already decided to do – meant bumping up the guesstimated weight of the universe by 80 percent, with nothing to explain what all that mass actually was. Dark matter is widely accepted as real among physicists, but is still more a "mystery filler" substance than an actual, explainable phenomenon.

Unlike most research about dark matter, Adler's 2008 analysis tried to pin blame for a specific micro-event on a massive, invisible force whose invisibility shows our inability to see the answer to a question we can't quite understand, or could be a fantasy created to make the math work until someone can put a finger on a more obvious and simple mistake.

One anomalous speed reading during a single flyby isn't much to hang a major proof on, however.

A dense ring of closely watched, constantly managed spacecraft in a sphere covering almost every inch of the Earth make a decent set of measurement tools. Unlike wide-orbiting, long-distance probes, GPS satellites fly in tight, precisely ordered and measured orbits that are constantly measured and adjusted by ground crews to keep each in exactly the right place to let GPS systems on the ground get consistent calculations of their own locations.

Harris took nine months of data from the U.S. network of GPS satellites, the Russian GLONASS GPS network and European Galileo satellites and started looking for differences between what the Earth's pull actually was compared to what it was supposed to be.

"The nice thing about GPS satellites is that we know their orbits really, really well," he told New Scientist.  (http://www.newscientist.com/article/mg22129503.100-gps-satellites-suggest-earth-is-heavy-with-dark-matter.html)which posted a story Jan. 2 about his talk in mid-December.

Harris, who made an oral presentation of his findings but had no paper showing the data and calculations for other scientists to vet, and admitted his calculations were preliminary and presentation incomplete.

He hadn't calculated the effect of relativity on the orbits of the satellites for example, he warned New Scientist. He also hadn't yet accounted for the gravitational pull of the sun and moon or other possible influences.

Other data presented at the same meeting suggested the Juno probe was not, in fact, speeding when it passed by the Earth which, if true, would have made Harris' conclusion more tentative.

Harris concluded that the mass of Earth is between .005 percent and .008 percent higher than the figure that had been accepted almost universally since the IAU calculated it 50 years ago.

It's not like discovering an invisible new moon, but is still a pretty significant mistake, if that's what it was.

Not everyone agrees the mistake is in the IAU's figures, or even that Harris has presented enough information to know anything new about either dark matter or the Earth.

Making elaborate claims in oral presentations, without nailing down all the variables that could keep a set of results from being twisted into something more interesting than the truth is a red flag for any scientific presentation, let alone one making audacious claims about the way dark matter behaves or weight of the Earth, according to an exasperated counterargument from Matthew R. Francis, (http://bowlerhatscience.files.wordpress.com/2014/01/resume_matthew-r-francis.pdf) who earned a Ph.D. in physics and astronomy from Rutgers in 2005, held visiting and assistant professorships at several Northeastern universities and whose science writing has appeared in Ars Technica, The New Yorker, Nautilus, BBC Future and others including his own science blog at Galileo's Pendulum. (http://galileospendulum.org/2014/01/02/no-dark-matter-is-not-messing-up-gps-measurements/)

Dark matter might clump up around Earth as Harris suggested, but only if its particles pull more strongly on each other than most physicists expect. If they do, and if it has gathered in unlikely density around the Earth, it could have a measurable gravitational effect, but even the mass of the sun hasn't attracted dense, powerful clumps of dark matter, at least not that anyone has discovered, Francis wrote.

Prevailing theories about dark matter paint is as being much more evenly distributed throughout the galaxy, at densities equivalent to about 600 electrons within the area of a cube a centimeter on each side. In human terms that's something lower than undetectable, not something likely to create more pull on a satellite than anyone had previously found or failed to explain more simply.

Dark matter is not space dirt; it hardly interacts with "normal" matter at all.

Particles of dark matter, like Higgs Bosons, neutrinos and other particles that are difficult for humans even to detect, pass straight through each of us all the time, though "whether you find that creepy or not depends on your mindset" and how many are doing it at an one time depends on what dark matter will actually turn out to be.

"To dark matter, you're basically transparent," Francis wrote.

Francis' Jan. 2 blog entry carries the tag "debunkery," but he doesn't say Harris' conclusions are wrong, criticize his research methods or even accuse Harris of anything unsavory.

He does complain that Harris presented his conclusions and got publicity from New Scientist for them without having passed through the gauntlet of skepticism and peer review designed to filter most of the mistakes out of new research before it's published, with its data and methodology exposed so the rest of its faults can be pummeled away.

Conferences like the one at which Harris spoke are "good opportunities to present ideas that might or might not be publishable in journals," Francis wrote.

"Not publishable" can mean good science that has not yet been sufficiently vetted but ultimately will be, and complete quackery, though Francis doesn't even address which Harris' work might be.

The problem isn't the quality of the work, or its conclusions. The problem is that it was presented in too informal a way for other scientists to judge its quality, given more exposure by the New Scientist writeup and went proto-viral through the geekosphere as it was picked up writers and editors [ahem] who recognized the potential impact of Harris' results without looking hard enough at the data supporting his conclusions.

"I've seen (and even given) talks based on preliminary research that aren't ready yet, and I suspect this talk fell into that category," Francis wrote. "When Harris has taken general relativity and the effects of the Sun and Moon into account and if he still sees this phenomenon, then we might have something to talk about."

Francis added a sentence concluding that dark matter does not play a role in the motion of GPS satellites, but I left that out in deference to his concern about accuracy. Even if every word Harris said was wrong, it would only mean we have no idea whether dark matter can affect satellites, any more than we would know whether it likes to clump, gather in halos around tiny gravity wells or whether it resents being called dark and mysterious just because one planet's biological infection can't see well enough to detect 80 percent of the universe.

Better to just skip that discussion altogether.

Takođe:
   Stellar Trio Could Put Einstein's Theory of Gravity to the Test (http://news.sciencemag.org/physics/2014/01/stellar-trio-could-put-einsteins-theory-gravity-test)

QuoteIn a cosmic coup, astronomers have found a celestial beacon known as a pulsar in orbit with not one, but two other stars. The first-of-its-kind trio could soon be used to put Einstein's theory of gravity, or general relativity, to an unprecedented test. "It's a wonderful laboratory that nature has given us," says Paulo Freire, a radio astronomer at the Max Planck Institute for Radio Astronomy in Bonn, Germany, who was not involved in the work. "It's almost made to order."
A pulsar consists of a neutron star, the leftover core of a massive star that has blown up in a supernova explosion. The core's own gravity squeezes it so intensely that the atomic nuclei meld into a single sphere of neutrons. The spinning neutron star also shines out a beam of radio waves that sweeps the sky just as the light beam from a lighthouse sweeps the sea. In fact, pulsars flash so regularly that they make natural timepieces whose ticking can be as steady as that of an atomic clock.
The incredible regularity makes it possible to determine whether the pulsar is in orbit with another object, as roughly 80% of the more than 300 fast-spinning "millisecond" pulsars are known to be. As the pulsar and its companion orbit each other, the distance between the pulsar and Earth varies slightly, so that it takes more or less time for the pulses of radio waves to reach Earth. As a result, the frequency of pulsing speeds up and slows down in a telltale cycle.
But such a simple scenario couldn't explain the peculiar warbles in the frequency of pulsar PSR J0337+1715, which Scott Ransom, an astronomer at the National Radio Astronomy Observatory in Charlottesville, Virginia, and colleagues discovered in 2007 with the Robert C. Byrd Green Bank Telescope in West Virginia. Training other radio telescopes on the object, Ransom and colleagues kept it under near-constant surveillance for a year and a half. Eventually, Anne Archibald, a graduate student at McGill University in Montreal, Canada, figured out exactly what's going on.
The pulsar, which has 1.4 times the sun's mass and spins 366 times a second, is in a tight orbit lasting 1.6 days with a white dwarf star only 20% as massive as the sun. A second white dwarf that weighs 41% as much as the sun orbits the inner pair every 327 days, as Ransom and colleagues report online today in Nature (http://dx.doi.org/10.1038/nature12917). "We think that there are not more than 100 of these [trios] in our galaxy," Ransom says. "They really are one-in-a-billion objects."
The distinctive new system opens the way for testing a concept behind general relativity known as the equivalence principle, which relates two different conceptions of mass. An object's inertial mass quantifies how it resists pushing or pulling: It's easier to start a stroller rolling than a car because the stroller has less inertial mass. A thing's gravitational mass determines how much a gravitational field pulls on it: A barbell is heavier than a feather because it has more gravitational mass.
The simplest version of the equivalence principle says inertial mass and gravitational mass are equal. It explains why ordinary objects like baseballs and bricks fall to Earth at the same rate regardless of their mass—as legend claims Galileo showed by dropping heavier and lighter balls from the Leaning Tower of Pisa.
The strong equivalence principle takes things an important step further. According to Einstein's famous equation, E = mc², energy equals mass. So an object or system's mass can be generated by the energy in the gravitational fields within the system itself. The strong equivalence principle states that even if one includes mass generated through such "self-gravitation," gravitational and inertial mass are still equal. The principle holds in Einstein's theory of general relativity but typically does not hold in alternative theories, says Thibault Damour, a theoretical physicist at the Institute for Advanced Scientific Studies in Bures-sur-Yvette, France. So poking a pin in the principle would prove that general relativity is not the final word on gravity.
Researchers have already tried to test the strong equivalence principle. Since the 1970s, some have compared how the moon and Earth orbit in the gravitational field of the sun. More recently, others have analyzed the motion of pulsar–white dwarf pairs in the gravitational field of the galaxy. But those studies have been limited, Damour says. Earth's self-gravitation accounts for just a billionth of its mass. In pulsar studies, the galaxy's gravity is very weak. So the strong equivalence principle has been tested only to a precision of parts per thousand.
The new pulsar system opens the way to a much more stringent test by combining the strengths of the two previous methods. The self-gravitation of the pulsar accounts for roughly 10% of its mass, in contrast to less than 0.001% for the inner white dwarf. At the same time, both move in the gravitational field of the outer white dwarf, which is much stronger than the field of the galaxy. By tracking the system's evolution, Ransom and colleagues should be able to tell whether either the inner white dwarf or the pulsar falls faster toward the outer white dwarf and test strong equivalence about 100 times as precisely as before, Damour says.
So will strong equivalence principle be found wanting? "I would rather expect to get a better limit" on possible violations, Damour says. "But I'm open-minded. It would be great to get a violation." Freire says a violation would be "a complete revolution."
Researchers may not have to wait long, Ransom says. His team should be able to test the principle within a year.
   

Nećemo otvarati nove topike samo zato što je neko konačno uspeo da sintetiše i stabilizuje (well, sort of) antivodonik!!!!!!!


Antimatter experiment produces first beam of antihydrogen (http://home.web.cern.ch/about/updates/2014/01/antimatter-experiment-produces-first-beam-antihydrogen)

Quote
The ASACUSA experiment (http://home.web.cern.ch/about/experiments/asacusa) at CERN has succeeded for the first time in producing a beam of antihydrogen atoms. In a paper published today in Nature Communications (http://www.nature.com/ncomms/index.html), the ASACUSA collaboration reports the unambiguous detection of 80 antihydrogen atoms 2.7 metres downstream of their production, where the perturbing influence of the magnetic fields used initially to produce the antiatoms is small. This result is a significant step towards precise hyperfine spectroscopy of antihydrogen atoms.
Primordial antimatter (http://home.web.cern.ch/topics/antimatter) has so far never been observed in the universe, and its absence remains a major scientific enigma. Nevertheless, it is possible to produce significant amounts of antihydrogen in experiments at CERN by mixing antielectrons (positrons) and low energy antiprotons produced by the Antiproton Decelerator (http://home.web.cern.ch/about/accelerators/antiproton-decelerator).
The spectra of hydrogen and antihydrogen are predicted to be identical, so any tiny difference between them would immediately open a window to new physics, and could help in solving the antimatter mystery (http://home.web.cern.ch/topics/antimatter/matter-antimatter-asymmetry-problem). With its single proton accompanied by just one electron, hydrogen is the simplest existing atom, and one of the most precisely investigated and best understood systems in modern physics. Thus comparisons of hydrogen and antihydrogen atoms constitute one of the best ways to perform highly precise tests of matter/antimatter symmetry.
Matter and antimatter annihilate immediately when they meet, so aside from creating antihydrogen, one of the key challenges for physicists is to keep antiatoms away from ordinary matter. To do so, experiments take advantage of antihydrogen's magnetic properties (which are similar to hydrogen's) and use very strong non-uniform magnetic fields to trap antiatoms long enough to study them. However, the strong magnetic field gradients degrade the spectroscopic properties of the (anti)atoms. To allow for clean high-resolution spectroscopy, the ASACUSA collaboration developed an innovative set-up to transfer antihydrogen atoms to a region where they can be studied in flight, far from the strong magnetic field.
"Antihydrogen atoms having no charge, it was a big challenge to transport them from their trap. Our results are very promising for high-precision studies of antihydrogen atoms, particularly the hyperfine structure, one of the two best known spectroscopic properties of hydrogen. Its measurement in antihydrogen will allow the most sensitive test of matter/antimatter symmetry. We are looking forward to restarting this summer with an even more improved set-up," says Yasunori Yamazaki of RIKEN, Japan, a team leader of the ASACUSA collaboration. The next step for the ASACUSA experiment will be to optimize the intensity and kinetic energy of antihydrogen beams, and to understand better their quantum state.
Progress with antimatter experiments at CERN has been accelerating in recent years. In 2011, the ALPHA (http://home.web.cern.ch/about/experiments/alpha) experiment announced trapping of antihydrogen atoms for 1000 seconds (http://press.web.cern.ch/press-releases/2011/06/cern-experiment-traps-antimatter-atoms-1000-seconds) and reported observation of hyperfine transitions of trapped antiatoms (http://press.web.cern.ch/press-releases/2012/03/cern-experiment-makes-spectroscopic-measurement-antihydrogen) in 2012. In 2013, the ATRAP (http://home.web.cern.ch/about/experiments/atrap) experiment announced the first direct measurement of the antiproton's magnetic moment (http://press.web.cern.ch/press-releases/2013/03/atrap-experiment-makes-worlds-most-precise-measurement-antiproton-magnetic) with a fractional precision of 4.4 parts in a million.
Read the paper: "A source of antihydrogen for in-flight hyperfine spectroscopy (http://www.nature.com/ncomms/2014/140121/ncomms4089/full/ncomms4089.html)" – Nature Communications
 

   
• Français (http://home.web.cern.ch/fr/about/updates/2014/01/antimatter-experiment-produces-first-beam-antihydrogen)

Posted by Cian O'Luanaigh (http://profiles.web.cern.ch/717206) on 21 Jan 2014. Last updated 21 Jan 2014, 17.36.   
Topic Antimatter (http://home.web.cern.ch/topics/antimatter)

   
• The matter-antimatter asymmetry problem (http://home.web.cern.ch/topics/antimatter/matter-antimatter-asymmetry-problem)

Sigurno ste se nekad upitali da li neka planeta može da ima oblik torusa (krofne). Gle čuda, može:

http://io9.com/what-would-the-earth-be-like-if-it-was-the-shape-of-a-d-1515700296 (http://io9.com/what-would-the-earth-be-like-if-it-was-the-shape-of-a-d-1515700296)

A, jel' može kao ćevap? Neverending krk&look.

Torus je stabilan, treba samo da se obrće odgovarajućom brzinom. Planeta bi mogla da bude samo od vode, i opet bi se nekako držala. Ćevap bi se, s druge strane, urušio u ćuftu.

    Pluto's Moons Are Even Weirder Than Thought (http://www.space.com/29559-pluto-moons-weird-orbit-chaos.html)

Quote
Pluto's moons are even stranger and more intriguing than scientists imagined, a new study reveals.

The Pluto (http://www.space.com/16537-pluto-quiz-dwarf-planet-moons.html) system consists of four tiny satellites — Nix, Hydra, Kerberos and Styx — orbiting a "binary planet" comprised of Pluto and its largest moon Charon, which, at 750 miles (1,207 kilometers) in diameter, is nearly half as wide as the dwarf planet itself.

This binary setup has profoundly influenced the orbits of the four small moons, injecting chaos into their movements — as depicted in a newly released animation of tumbling Nix (http://www.space.com/29561-spuds-in-space-pluto-moon-s-weird-spin-animated-video.html) — in ways not fully appreciated until now, the study suggests. [Photos of Pluto and Its Moons (http://www.space.com/11431-photos-pluto-charon-moons-dwarf-planet.html)]
"It's a very strange place to live in if you are orbiting a binary planet (http://www.space.com/28545-pluto-charon-wobbly-dance-proves-it-s-a-double-planet-video.html)," lead author Mark Showalter, of the SETI (Search for Extraterrestrial Intelligence) Institute in Mountain View, California, told Space.com. Brightness and size
Showalter and co-author Douglas Hamilton, of the University of Maryland, analyzed images of the Pluto system taken by NASA's Hubble Space Telescope (http://www.space.com/15892-hubble-space-telescope.html) between 2005 and 2012. (During this period, the observatory discovered all four of the dwarf planet's tiny known moons; Showalter led the teams that detected Kerberos and Styx.)

The two researchers used these photos — which captured brightness variations of the moons over time — and computer models to characterize the four small satellites and their orbits in unprecedented detail.

For example, Showalter and Hamilton derived new brightness and size estimates for the moons. They found that Nix and Hydra are likely about as bright as Charon (http://www.space.com/26250-pluto-moon-charon-subsurface-ocean.html), which reflects roughly 40 percent of the light that hits it.

Before the new study, "we didn't really know how big Nix and Hydra were, because we didn't know how bright they were," Showalter said. "And now, based on our analysis, we actually do pretty well know how big and how bright they are, so there are a lot of uncertainties about the properties of Nix and Hydra that have gone away now."
The Hubble images suggest that Hydra is around 28.2 miles (45.4 km) across, while Nix has a diameter of 24.6 miles (39.6 km) or so. Kerberos and Styx, meanwhile, are probably about 15.4 miles (24.8 km) and 4.2 miles (6.8 km) wide. (These latter two moons are tougher to characterize, because they are fainter than Nix and Hydra.)

These diameter estimates assume a spherical shape for the moons, which is likely not the reality; most if not all of the four tiny satellites are probably ellipsoidal, researchers said.

The duo's analysis also suggests that Kerberos is much darker than its fellow satellites, with a reflectivity of just 4 percent. Whereas Nix and Hydra are basically "dirty snowballs" in terms of reflectivity, "Kerberos is a charcoal briquet," Showalter said. [Pluto's 5 Moons Explained (Infographic) (http://www.space.com/16538-pluto-moons-explained-infographic.html)]

This result "took us completely by surprise, because everybody has been assuming all along that the moons would be pretty similar," he added. "They all probably formed at the same time; they all are made of the same stuff."

Astronomers think Pluto's four small moons were formed from the debris scattered by a long-ago giant impact between a proto-Pluto object and a proto-Charon. Perhaps the proto-Charon was a very dark body, and Kerberos is a relatively pristine piece of this original impactor, Showalter said, though he stressed that this idea is mere speculation.   Resonance and chaos
Showalter and Hamilton also determined that Styx, Nix and Hydra are linked by a "resonance," a sort of gravitational sweet spot in which orbits of multiple celestial bodies are related by a ratio of two whole numbers. A similar three-body resonance is found among the Jupiter moons Io, Europa and Ganymede, the researchers said.

"The resonant relationship between Nix, Styx and Hydra makes their orbits more regular and predictable, which prevents them from crashing into one another," Hamilton said in a statement (https://www.umdrightnow.umd.edu/latest-news). "This is one reason why tiny Pluto is able to have so many moons."

But there is also quite a bit of chaos in the Pluto system, imparted by the complex and shifting gravitational field of the Pluto-Charon binary.
For instance, Showalter and Hamilton found that Nix and Hydra exhibit chaotic rather than synchronous rotation, meaning they don't always keep the same side facing Pluto-Charon — and that it's very tough to predict their rotational movement. (Nearly every other moon in the solar system, including Earth's, is a synchronous rotator.)

"If you lived on Nix, you would not know if the sun is coming up tomorrow; it is that extreme," Showalter said, adding that models suggest that Styx and Kerberos are chaotic rotators as well. "You'd have days where the sun rises in the east and sets in the north."

Such findings could help researchers better understand the many alien planets that orbit binary stars, researchers said.

"We are learning that chaos may be a common trait of binary systems," Hamilton said. "It might even have consequences for life on planets orbiting binary stars."  New Horizons and beyond
The new study was published online in the journal Nature (http://nature.com/articles/doi:10.1038/nature14469) today (June 3), just six weeks ahead of the first-ever Pluto flyby. On July 14, NASA's New Horizons spacecraft will zoom within 7,800 miles (12,500 km) of the dwarf planet's surface.

New Horizons should get good looks at the surfaces of Nix and Hydra, and the probe's observations will likely reveal how dark Kerberos is, Showalter said.

Data from the flyby, as well as continued long-term monitoring by Hubble and NASA's James Webb Space Telescope, which is scheduled to launch in 2018, could end up bringing Pluto's moons into sharp focus, he added.

"We've got pieces to start fitting together, and maybe eventually out of this we'll get a whole formation scenario for the [Pluto] system," Showalter said.

Na linku imaju i slike i video.

Itan Sigel spekuliše:

Kolonija treba da bude isplativa, ili ekonomski ili tako što će oni koji uspostave koloniju steći neka nova saznanja. Mesec nudi par dobrih razloga za kolonizaciju (Helijum-3, materijal za neku masovnu proizvodnju satelita oko Zemlje), ali na Veneri trenutno nema ništa interesantno.

Opet Itan:
Why Is Our Solar System Missing The Universe's Most Common Planet? (http://www.forbes.com/sites/ethansiegel/2015/07/11/why-is-our-solar-system-missing-the-universes-most-common-planet/)

The New, Nerdy Mythology of Pluto's Place Names (http://www.wired.com/2015/07/new-nerdy-mythology-plutos-place-names/?mbid=social_twitter)

Quote
Once you have pictures of a never-before-seen-up-close almost-planet, you have to start naming what you see. And according to an image of  from the New Horizons press room that our correspondent Nick Stockton tweeted earlier today, the Plutonians have started naming their surroundings...informally. 

The names are all related to various mythologies of the underworld, appropriately enough. They also suggest that some of these researchers are pretty darn nerdy—though some of the names seem to have come from  during New Horizons' flight.

Like, for example, "Cthulu," the name of an elder god from the fiction of HP Lovecraft. Or what about "Balrog," the name of the monster that seemingly killed Gandalf the Grey in the Lord of the Rings trilogy? Meng-p'o is the Buddhist goddess of forgetfulness and amnesia—she lives in the underworld. Hun-Came and Vucub-Came are Mayan death gods.

We thought at first that Krun was a reference to a Non-Player Character from the hellfire peninsula in World of Worldcraft, but he's actually one of five lords of the underworld for the Mandaeans, an ancient religion from the Iraq-Iran region. (His nickname is "Mountain-of-Flesh.") Ala is an underworld and harvest goddess of the Ibo people of eastern Nigeria.

Pluto might not technically be a planet, but it has some great place-names.

NASA just found something big hiding out behind Pluto (http://finance.yahoo.com/news/nasa-just-found-something-big-205800491.html)

Quote

NASA and the team behind its New Horizons spacecraft announced today that Pluto — the dwarf planet — has a giant tail.

It's not a physical tail like a dog's, of course, but rather a frigid cloud of ionized gases trailing an estimated 48,000 to 68,000 miles behind Pluto, according to a NASA press release (http://www.nasa.gov/nh/pluto-wags-its-tail).

This giant tail is actually part of Pluto's atmosphere. Except that the bits of atmosphere are being stripped away by solar wind, a torrent of electrically charged particles that constantly pours out of the sun in all directions.

"We see the atmosphere way far out," Randy Gladstone, a New Horizons coinvestigator at Southwest Research Institute in San Antonio, said during a NASA press conference on Friday. "We see it from the ground out to 1,000 miles above the surface."

Because Pluto is such a tiny planet — it's a fraction of a percent as massive as the Earth — its atmosphere escapes directly into space, Gladstone said.

Gladstone and others discovered the tail after examining data from the Solar Wind Around Pluto (SWAP) instrument on the New Horizons spacecraft. The device found an anomaly in the solar wind around the dwarf planet: A depression composed of nitrogen ions (http://www.nasa.gov/nh/pluto-wags-its-tail). This depression is the tail, and it extends an unknown length behind the planet.

"We have actually flown through this [tail]," Fran Bagenal, a New Horizons coinvestigator from the University of Colorado at Boulder, said during the press conference.

Ionized gas (http://education.jlab.org/qa/plasma_01.html) forms when a bunch of energy pummels atmospheric atoms and molecules. This bombardment pops electrons off the atmospheric gas particles, allowing their electrons to freely circulate. The end result is plasma: A fourth state of matter after solids, liquids, and gases.

As far as we know, plasma is the most common state of matter in the universe (http://education.jlab.org/qa/plasma_01.html). There's simply a lot of energy pouring out of stars, and a lot of gas in space to form plasma. So while it might seem surprising, plasma tails like Pluto's aren't new. They even exist behind other planets in the solar system, including Venus and Mars (https://www.nasa.gov/feature/how-big-is-pluto-new-horizons-settles-decades-long-debate).

The team still hasn't determined the precise shape of Pluto's newly discovered tail. They also don't know exactly how the was formed.

So NASA is anxiously waiting for New Horizons to beam back more data (http://www.businessinsider.com/why-it-takes-so-long-for-new-horizons-to-send-images-2015-7). By August the team hopes to calculate how fast Pluto is losing its atmosphere to space — and, likewise, how quickly the icy world is shrinking.

NOW WATCH: Scientists just discovered 11,000-foot ice mountains, geysers and volcanoes on Pluto (http://www.businessinsider.com/pluto-ice-mountains-geysers-volcanos-nasa-2015-7)

Universe Is Dying, Galactic Survey Shows (http://news.discovery.com/space/galaxies/universe-is-dying-galactic-survey-shows-150810.htm)

Quote
A study of more than 200,000 galaxies, encompassing wavelengths of light from the far ultraviolet to infrared, shows that the universe is producing half as much energy as it did 2 billion years ago and continues to fade.
"Newer galaxies are simply putting out less energy than galaxies did in the past," astronomer Mehmet Alpaslan, with NASA's Ames Research Center in Mountain View, Calif., told Discovery News.Older stars are fading out faster than new stars are forming, a trend that eventually will leave the universe a cold and lonely place. "At some point, all matter will eventually decay. We're observing the lights slowly shutting down," Alpasian said.
"The timeline for all this to come to pass is very long, hundreds of trillions of years," he added.
The study, released Monday at the International Astronomical Union conference in Hawaii, culminates a seven-year, international effort to measure both the distances and energy output of more than 200,000 galaxies.
Seven observatories, including Europe's Visible and Infrared Survey Telescope for Astronomy (VISTA) and its VLT Survey Telescope, both at the Paranal Observatory in Chile, contributed to the study. Other data came from NASA's Wide-field Infrared Survey Explorer (WISE) and its now-defunct Galaxy Evolution Explorer (GALEX) space telescopes, and European Space Agency's retired Herschel space telescope.


"GAMA is the first survey to study a large number of galaxies and map the energy outputs over the range where most of the energy comes out," lead scientist Simon Driver, with the University of Western Australia, wrote in an email to Discovery News.
Scientists have known since the late 1990s that the universe is slowly fading, but the GAMA study is the first to measure galaxies' radiation across the spectrum. Measurements were made at 21 wavelengths, ranging from the far ultraviolet to the infrared.
"You're probing a lot of different kinds of physics when you look at a lot of different energy," Alpaslan said. "Having the homogeneous data set makes it a lot easier to fully understand what is going on in a galaxy across all these different kinds of physics."
The decline in galaxies' energy output coincides with the universe's ever-increasing rate of expansion, which is due to a mysterious, anti-gravity force referred to as dark energy.


Astronomers now plan to use the GAMA data for a variety of studies, such as understanding how different types of stars form and evolve in different kinds of environments; the rates at which galaxies are merging; and how those merges impact the galaxies' evolution.
"We're phasing toward doing more science with the data, rather than just analyzing," Alpaslan said. "We've surveyed a large enough region for this to be representative."
The GAMA team's research has been submitted for publication in the Monthly Notices of the Royal Astronomical Society.

Quote from: Meho Krljic on 12-08-2015, 10:18:49
Universe Is Dying, Galactic Survey Shows (http://news.discovery.com/space/galaxies/universe-is-dying-galactic-survey-shows-150810.htm)

Quote
A study of more than 200,000 galaxies, encompassing wavelengths of light from the far ultraviolet to infrared, shows that the universe is producing half as much energy as it did 2 billion years ago and continues to fade.
"Newer galaxies are simply putting out less energy than galaxies did in the past," astronomer Mehmet Alpaslan, with NASA's Ames Research Center in Mountain View, Calif., told Discovery News.Older stars are fading out faster than new stars are forming, a trend that eventually will leave the universe a cold and lonely place. "At some point, all matter will eventually decay. We're observing the lights slowly shutting down," Alpasian said.
"The timeline for all this to come to pass is very long, hundreds of trillions of years," he added.
The study, released Monday at the International Astronomical Union conference in Hawaii, culminates a seven-year, international effort to measure both the distances and energy output of more than 200,000 galaxies.
Seven observatories, including Europe's Visible and Infrared Survey Telescope for Astronomy (VISTA) and its VLT Survey Telescope, both at the Paranal Observatory in Chile, contributed to the study. Other data came from NASA's Wide-field Infrared Survey Explorer (WISE) and its now-defunct Galaxy Evolution Explorer (GALEX) space telescopes, and European Space Agency's retired Herschel space telescope.


"GAMA is the first survey to study a large number of galaxies and map the energy outputs over the range where most of the energy comes out," lead scientist Simon Driver, with the University of Western Australia, wrote in an email to Discovery News.
Scientists have known since the late 1990s that the universe is slowly fading, but the GAMA study is the first to measure galaxies' radiation across the spectrum. Measurements were made at 21 wavelengths, ranging from the far ultraviolet to the infrared.
"You're probing a lot of different kinds of physics when you look at a lot of different energy," Alpaslan said. "Having the homogeneous data set makes it a lot easier to fully understand what is going on in a galaxy across all these different kinds of physics."
The decline in galaxies' energy output coincides with the universe's ever-increasing rate of expansion, which is due to a mysterious, anti-gravity force referred to as dark energy.


Astronomers now plan to use the GAMA data for a variety of studies, such as understanding how different types of stars form and evolve in different kinds of environments; the rates at which galaxies are merging; and how those merges impact the galaxies' evolution.
"We're phasing toward doing more science with the data, rather than just analyzing," Alpaslan said. "We've surveyed a large enough region for this to be representative."
The GAMA team's research has been submitted for publication in the Monthly Notices of the Royal Astronomical Society.

Sveža vest, bokte, nismo pojma imali, ono jeste da je Klauzijus otkrio drugi zakon termodinamike još 1850. a Vilijam Tomson iz toga izveo ideju o toplotnoj smrti vasione sledeće godine...

Quote from: mac on 11-09-2010, 01:23:42
Sad bi bar moglo da padne više detalja o tom konkursu, ili šta li je već bio. I malo konkretnije o vašoj ideji.

Džebote, tek sam sada video Macovo pitanje od pre pet godina. I'm an idiot.

Elem, reč je bila o konkursu koji se zvao Worldbuilding (ili tako nešto) i sastojao se od faza. Prva faza je bila "izrada" naučno uverljive planete/sveta/objekta negde u svemiru. Dakle, to je mogla da bude planeta, neko veštačko telo ili šta već, ali uslov je bio da to telo bude  dovoljno veliko da bi se na njemu razvio stabilan ekosistem, pa onda i civilizacija. Druga faza je bila upravo civilizacija/kultura, ali na odabranom nebeskom telu. Dakle, svi učesnici koji prođu u drugi krug morali bi da za svoju planetu/šta već uzmu pobednika iz prvog kruga. U trećoj fazi se pišu priče, koje se odigravaju u okvirima civilizacije/kulture koja je pobedila u drugoj fazi.

Mene je moja grupa angažovala zbog civilizacijskog aspekta, ali nismo prošli ni u drugu fazu :)

QuoteSveža vest, bokte, nismo pojma imali, ono jeste da je Klauzijus otkrio drugi zakon termodinamike još 1850. a Vilijam Tomson iz toga izveo ideju o toplotnoj smrti vasione sledeće godine...

A Pamela Zoline potvrdila u kultnoj priči novog talasa "The Heat Death of the Universe" (vidi neki stari SIRIUS)...  :)

Ili vidi ovde

http://future-lives.com/wp-content/uploads/2014/09/zoline_heat-death.pdf (http://future-lives.com/wp-content/uploads/2014/09/zoline_heat-death.pdf)

Naravno! Ja sam je prvi put čitala u tematu Reči posvećenom entropiji, koji je uredio Novica Petrović. Divan temat bio, i Pinčon i Balard i sve sve :)

Quote from: Nightflier on 12-08-2015, 17:02:33
Mene je moja grupa angažovala zbog civilizacijskog aspekta, ali nismo prošli ni u drugu fazu :)

Možda je problem bio to što se vaš ekosistem nije nešto bitno razlikovao od ovdašnjeg zemaljskog. Ako sam dobro razumeo vaša ideja je bila crna rupica mase Meseca koja je uvek skrivena sa druge strane vidljivog satelita, koji kruži oko planete osetno (ali ne previše) veće od Zemlje, ali sa Zemljinom gravitacijom.

Koji su rezultati konkursa? Koje ekološke ideje su prošle dalje, i šta je na kraju pobedilo? Ima li neki link?

Prestao sam da pratim negde na polovini druge faze. Na kraju su neke priče napisane i objavljene na nekoj onlajn platformi - da li Wattpadu ili tako nečemu, ali više se ne sećam.

 Has Stephen Hawking Just Solved a Huge Black-Hole Mystery? (http://www.space.com/30366-stephen-hawking-black-hole-mystery.html)

Quote
Stephen Hawking may have just solved one of the most vexing mysteries in physics — the "information paradox."

Einstein's theory of general relativity predicts that the physical information about material gobbled up by a black hole (http://www.space.com/15906-black-hole-quiz-facts.html) is destroyed, but the laws of quantum mechanics stipulate that information is eternal. Therein lies the paradox.

Hawking — working with Malcolm Perry, of the University of Cambridge in England, and Harvard University's Andrew Stromberg — has come up with a possible solution: The quantum-mechanical information about infalling particles doesn't actually make it inside the black hole.

"I propose that the information is stored not in the interior of the black hole, as one might expect, but on its boundary, the event horizon," Stephen Hawking (http://www.space.com/15923-stephen-hawking.html) said during a talk today (Aug. 25) at the Hawking Radiation conference, which is being held at the KTH Royal Institute of Technology in Stockholm, Sweden.

The information is stored at the boundary as two-dimensional holograms known as "super translations," he explained. But you wouldn't want super translations, which were first introduced as a concept in 1962, to back up your hard drive.

"The information about ingoing particles is returned, but in a chaotic and useless form," Hawking said. "For all practical purposes, the information is lost."

Hawking also discussed black holes — whose gravitational pull is so intense that nothing, not even light, can escape once it passes the event horizon — during a lecture last night (Aug. 24) in Stockholm.

It's possible that black holes could actually be portals to other universes, he said.

"The hole would need to be large, and if it was rotating, it might have a passage to another universe. But you couldn't come back to our universe," Hawking said at the lecture, according to a KTH Royal Institute of Technology statement (https://www.kth.se/en/aktuellt/nyheter/hawking-offers-new-solution-to-black-hole-mystery-1.586546). "So, although I'm keen on spaceflight, I'm not going to try that."

http://youtu.be/DkRDmJpthXg (http://youtu.be/DkRDmJpthXg)

Whoa!



Researchers catch Comet Lovejoy giving away alcohol  (http://www.eurekalert.org/pub_releases/2015-10/nsfc-rcc102315.php)

Quote
Comet Lovejoy lived up to its name by releasing large amounts of alcohol as well as a type of sugar into space, according to new observations by an international team. The discovery marks the first time ethyl alcohol, the same type in alcoholic beverages, has been observed in a comet. The finding adds to the evidence that comets could have been a source of the complex organic molecules necessary for the emergence of life.
"We found that comet Lovejoy was releasing as much alcohol as in at least 500 bottles of wine every second during its peak activity," said Nicolas Biver of the Paris Observatory, France, lead author of a paper on the discovery published Oct. 23 in Science Advances. The team found 21 different organic molecules in gas from the comet, including ethyl alcohol and glycolaldehyde, a simple sugar.
Comets are frozen remnants from the formation of our solar system. Scientists are interested in them because they are relatively pristine and therefore hold clues to how the solar system was made. Most orbit in frigid zones far from the sun. However, occasionally, a gravitational disturbance sends a comet closer to the sun, where it heats up and releases gases, allowing scientists to determine its composition.
Comet Lovejoy (formally cataloged as C/2014 Q2) was one of the brightest and most active comets since comet Hale-Bopp in 1997. Lovejoy passed closest to the sun on January 30, 2015, when it was releasing water at the rate of 20 tons per second. The team observed the atmosphere of the comet around this time when it was brightest and most active. They observed a microwave glow from the comet using the 30-meter (almost 100-foot) diameter radio telescope at Pico Veleta in the Sierra Nevada Mountains of Spain.
Sunlight energizes molecules in the comet's atmosphere, causing them to glow at specific microwave frequencies (if microwaves were visible, different frequencies would be perceived as different colors). Each kind of molecule glows at specific, signature frequencies, allowing the team to identify it with detectors on the telescope. The advanced equipment was capable of analyzing a wide range of frequencies simultaneously, allowing the team to determine the types and amounts of many different molecules in the comet despite a short observation period.
Some researchers think that comet impacts on ancient Earth delivered a supply of organic molecules that could have assisted the origin of life. Discovery of complex organic molecules in Lovejoy and other comets gives support to this hypothesis.
"The result definitely promotes the idea the comets carry very complex chemistry," said Stefanie Milam of NASA's Goddard Space Flight Center in Greenbelt, Maryland, a co-author on the paper. "During the Late Heavy Bombardment about 3.8 billion years ago, when many comets and asteroids were blasting into Earth and we were getting our first oceans, life didn't have to start with just simple molecules like water, carbon monoxide, and nitrogen. Instead, life had something that was much more sophisticated on a molecular level. We're finding molecules with multiple carbon atoms. So now you can see where sugars start forming, as well as more complex organics such as amino acids -- the building blocks of proteins -- or nucleobases, the building blocks of DNA. These can start forming much easier than beginning with molecules with only two or three atoms."
In July, the European Space Agency reported that the Philae lander from its Rosetta spacecraft in orbit around comet 67P/Churyumov­-Gerasimenko detected 16 organic compounds as it descended toward and then bounced across the comet's surface. According to the agency, some of the compounds detected play key roles in the creation of amino acids, nucleobases, and sugars from simpler "building-block" molecules.
Astronomers think comets preserve material from the ancient cloud of gas and dust that formed the solar system. Exploding stars (supernovae) and the winds from red giant stars near the end of their lives produce vast clouds of gas and dust. Solar systems are born when shock waves from stellar winds and other nearby supernovae compress and concentrate a cloud of ejected stellar material until dense clumps of that cloud begin to collapse under their own gravity, forming a new generation of stars and planets.
These clouds contain countless dust grains. Carbon dioxide, water, and other gases form a layer of frost on the surface of these grains, just as frost forms on car windows during cold, humid nights. Radiation in space powers chemical reactions in this frost layer to produce complex organic molecules. The icy grains become incorporated into comets and asteroids, some of which impact young planets like ancient Earth, delivering the organic molecules contained within them.
"The next step is to see if the organic material being found in comets came from the primordial cloud that formed the solar system or if it was created later on, inside the protoplanetary disk that surrounded the young sun," said Dominique Bockelée-Morvan from Paris Observatory, a co-author of the paper.

###

Milam was funded by a grant from the NASA Planetary Astronomy Program. The team included researchers from the Paris Observatory, CNRS (Centre National de la Recherche Scientifique, Paris), PSL Research University (Paris Sciences et Lettres, Paris), Bordeaux Observatory, France, IRAM (Institut de Radioastronomie Millimétrique, Grenoble, France) and Stockholm Observatory, Stockholm, Sweden, as well as from NASA. The 30-meter telescope used to make the team's observations is operated by IRAM, a collaboration among France, Germany, and Spain. IRAM is supported by INSU (Institut National des Sciences de l'univers)/CNRS (France), MPG (Max-Planck-Gesellschaft zur Förderung der Wissenschaften e. V.) (Germany), and IGN (Instituto Geográfico Nacional) (Spain).

I ja Love Joy i ponekad give away alcohol. xdrinka

 Teza koja ima smisla:  Earth Bloomed Early: A Fermi Paradox Solution? (http://www.space.com/30889-earth-bloomed-early-fermi-paradox-solution.html)

Quote
Our place in the universe is a conundrum — life on Earth evolved to create a technologically-savvy race that is now looking for other technologically-savvy intelligences populating our galaxy. But there's a problem; it looks like humanity is the only "intelligent" species in our little corner of the universe — what gives?

This question forms the basis of the Fermi Paradox: given the age of the universe and the apparent high probability of life evolving on other planets orbiting other stars, where are all the smart aliens?
According to a new study (http://hubblesite.org/newscenter/archive/releases/2015/35/full/) based on data collected by the NASA/ESA Hubble Space Telescope and NASA's Kepler Space Telescope, it might be that Earth (and all life on it) is an early bloomer. By extension, the logical progression from this new study is that we're not hearing from advanced alien civilizations because, in short, the universe hasn't had the time to spawn many more habitable worlds.

The study, which focuses purely on the likelihood of the evolution of habitable worlds (and not speculation of alien intelligence, the Fermi Paradox implication is my own), finds that when our planet was born from our young sun's protoplanetary disk some 4.6 billion years ago, it was born into an era when only "8 percent of the potentially habitable planets that will ever form in the universe existed." This means that the universe has 92 percent to go until it runs out of the necessary material to produce the stars that go on to produce planets, some of which will be small and rocky and orbit in just the right location for life (as we know it) to thrive.

"Our main motivation was understanding the Earth's place in the context of the rest of the universe," said Peter Behroozi of the Space Telescope Science Institute (STScI) in Baltimore, Md., "Compared to all the planets that will ever form in the universe, the Earth is actually quite early."

Hubble has shown astronomers that young galaxies were churning out stars at a fast rate some 10 billion years ago. However, the quantity of hydrogen and helium involved in stellar production was low compared with the amount of these star-forming gases that exist today.
"There is enough remaining material (after the Big Bang) to produce even more planets in the future, in the Milky Way and beyond," said Molly Peeples, also of STScI.

By combining this knowledge from Hubble with exoplanetary data from Kepler, the researchers were able to form a picture of the habitable planet potential of our galaxy and use it as a model for the number of other habitable worlds existing throughout the cosmos.

Since Kepler started taking data in 2009, we've been introduced to a menagerie of small rocky worlds orbiting sun-like stars. Some of these thousands of worlds orbit their stars within the habitable zone — the region surrounding a star that's not too hot and not too cold to allow liquid water to persist on its surface. By extrapolating from Kepler's comparatively small dataset, astronomers have predicted that there should be around 1 billion Earth-sized worlds orbiting within their stars' habitable zones in the Milky Way. If we consider there are 100 billion galaxies in the observable universe, there's a huge number of habitable, Earth-sized worlds throughout the cosmos.

And the universe, according to this new theoretical study, has only just started in the planetary production business. The last star isn't expected to fizzle out for another 100 trillion years (when the universe will continue toward its perpetual march to "heat death"), so there's lots of time left.
With the help of these observations, the researchers predict that Earth 2.0 (i.e. rocky planets of Earth-like dimensions orbiting within their stars' habitable zones) will most likely pop up inside giant galaxy clusters or dwarf galaxies where reservoirs of star-forming (and therefore planet-forming) gases are known to reside. Alas, the Milky Way's planet-forming days are numbered, as much of these gases have already been consumed during our galaxy's heady "starburst" days.

Noted by the researchers is that the advantage of being an "early" civilization evolving at this time of universal evolution is that we have the awesome opportunity to study the early stages of cosmic evolution, using space telescopes (such as Hubble) to see the early formation of galaxies and witness observable evidence for the Big Bang. For any future civilization in a trillion years time, the universe will look very different than it does now — fewer galaxies will be visible and the earliest evidence for the Big Bang (such as the cosmic microwave background radiation) will have further ebbed away.

It's interesting to ponder how an intelligent alien civilization will interpret a more mature, perpetually expanding universe lacking the cues to its origin that we take for granted today. Would they assume, lacking contradictory evidence, that the universe has always existed? And that just because the universe is expanding, it doesn't mean there had to be a Big Bang?
Of course, this is just a fun thought experiment; predicting the existence of a future alien intelligence, let alone how they may interpret their cosmic environment, is presumptuous at best. But it does pose an existential problem beyond the Fermi Paradox. If the Earth is an early bloomer, and humanity is one of the first intelligent civilizations to pop up in a universe of infinite possibilities, how might our civilization unfold?

Who knows, but it seems the universe has the boundless potential to form new worlds and new life (and new intelligences) that will potentially form long after humanity and life on Earth has come and gone, eventually succumbing to the inevitable death of our sun in about 5 billion years time. This study serves to remind us that our time as an intelligent life form in the universe is fleeting, and it seems many more intelligences will evolve long after we are gone.

Source: Hubblesite.org (http://hubblesite.org/newscenter/archive/releases/2015/35/full/)

Mystery Of Mars' Lost Atmosphere Solved At Last, Thanks To NASA's MAVEN Mission (http://www.forbes.com/sites/startswithabang/2015/11/05/mystery-of-mars-lost-atmosphere-solved-at-last-thanks-to-nasas-maven-mission/)

We've found the brightest ever supernova but can't explain it (https://www.newscientist.com/article/dn28772-weve-found-the-brightest-ever-supernova-but-cant-explain-it/)

Quote
The brightest supernova ever seen has been confirmed, but it still has astronomers puzzling over what unknown type of star could have been responsible.
Supernovas mark the violent deaths of stars that collapse on themselves and blow up. They are some of the brightest and most energetic objects in the universe.
This one, called ASASSN-15lh, is about 3.8 billion light years away, 200 times more powerful than most supernovas, and twice as bright as the previous record holder. It shines 20 times brighter than the combined output of the Milky Way's 100 billion stars, and in the last six months, it has spewed as much energy as the sun would in 10 lifetimes, says Krzysztof Stanek (http://www.astronomy.ohio-state.edu/%7Ekstanek/) of the Ohio State University, co-principal investigator of the All Sky Automated Survey for SuperNovae (ASAS-SN) network that spotted the explosion.
   "This is really on steroids, and then some," he says. "If it was in our own galaxy, it would shine brighter than the full moon; there would be no night, and it would be easily seen during the day."
He spotted the outburst on 14 June (https://www.newscientist.com/article/dn27879-record-breaking-super-bright-supernova-spotted-in-southern-sky) while perusing telescope images over his morning coffee, and alerted the rest of the ASAS-SN team, including Subo Dong (http://kiaa.pku.edu.cn/people/subo-dong) at the Kavli Institute for Astronomy and Astrophysics at Peking University. Dong quickly signalled a network of amateur astronomers who help the team confirm possible supernovae, and received some images that night.
The team suspected it was a rare "superluminous" supernova (https://www.newscientist.com/article/dn20554-meet-the-league-of-extraordinary-supernovae), but the 14-centimetre ASAS-SN telescopes were too small to see the details required to be sure. Bad weather and problems with instruments delayed further investigation by 10 days. Finally the Southern African Large Telescope revealed details about the star's chemical makeup when it exploded, allowing Dong to calculate its distance and confirm that the object was the brightest supernova ever recorded. It was 2 am in Beijing when Dong received these results, "but I was too excited to sleep the rest of the night", he says.


The supernova appears to be in an old, large galaxy that is bigger and brighter than the Milky Way, which is unusual because the handful of other known superluminous supernovas have been found in dim, small and young galaxies. It's also much hotter than other stellar explosions.
Mammoth or magnetar Those oddities mean astronomers are not totally sure what it is, Stanek says.
"My analogy is that we have been studying elephants, and our project has found the biggest elephant ever," he says. "There's a chance it is not an elephant, but a mammoth, a relic from the earlier universe."
It might be a different exotic object called a magnetar (https://www.newscientist.com/article/dn7032-distant-explosion-breaks-brightness-records), a special kind of neutron star with an intense magnetic field. But ASASSN-15lh is more powerful than magnetars can possibly become, so that seems unlikely, says Steve Rodney (http://www.physics.sc.edu/steven-rodney) at the University of South Carolina.
It could also be the remains of a star being pulled apart by a supermassive black hole, or an ordinary supernova that is being magnified by a cosmic lens, an effect of gravity. But both of those theories are unlikely: the explosion lacks the hydrogen and helium that would be the hallmarks of a black hole's lunch, and the explosion's relatively close distance makes lensing implausible.
ASASSN-15lh has just moved behind the sun, but astronomers have been taking new data until this week with the space-based Swift Gamma Ray Burst Explorer. The team was awarded time on the Hubble Space Telescope and hope to use it in a couple months – after the object fades a little bit, so the telescope can see its host galaxy in better detail. The Hubble observations will give astronomers more insight into the strange object's origins. Stanek says he's eager to hear new theories about what it could be.
"When you see something which has never been seen before, you get excited," he says. "It doesn't happen that often."
Journal: Science, 10.1126/science.aac9613

Proračuni i simulacije kažu da negde daleko van Kujperovog pojasa mora da postoji planeta mase desetak puta veće od Zemlje.

http://www.sciencemag.org/news/2016/01/feature-astronomers-say-neptune-sized-planet-lurks-unseen-solar-system (http://www.sciencemag.org/news/2016/01/feature-astronomers-say-neptune-sized-planet-lurks-unseen-solar-system)

Članak je dugačak pa ovde stavljam samo prvih par pasusa.

QuoteThe solar system appears to have a new ninth planet. Today, two scientists announced evidence that a body nearly the size of Neptune—but as yet unseen—orbits the sun every 15,000 years. During the solar system's infancy 4.5 billion years ago, they say, the giant planet was knocked out of the planet-forming region near the sun. Slowed down by gas, the planet settled into a distant elliptical orbit, where it still lurks today.

The claim is the strongest yet in the centuries-long search for a "Planet X" beyond Neptune. The quest has been plagued by far-fetched claims and even outright quackery. But the new evidence comes from a pair of respected planetary scientists, Konstantin Batygin and Mike Brown of the California Institute of Technology (Caltech) in Pasadena, who prepared for the inevitable skepticism with detailed analyses of the orbits of other distant objects and months of computer simulations. "If you say, 'We have evidence for Planet X,' almost any astronomer will say, 'This again? These guys are clearly crazy.' I would, too," Brown says. "Why is this different? This is different because this time we're right."

Outside scientists say their calculations stack up and express a mixture of caution and excitement about the result. "I could not imagine a bigger deal if—and of course that's a boldface 'if'—if it turns out to be right," says Gregory Laughlin, a planetary scientist at the University of California (UC), Santa Cruz. "What's thrilling about it is [the planet] is detectable."

Batygin and Brown inferred its presence from the peculiar clustering of six previously known objects that orbit beyond Neptune. They say there's only a 0.007% chance, or about one in 15,000, that the clustering could be a coincidence. Instead, they say, a planet with the mass of 10 Earths has shepherded the six objects into their strange elliptical orbits, tilted out of the plane of the solar system.

The orbit of the inferred planet is similarly tilted, as well as stretched to distances that will explode previous conceptions of the solar system. Its closest approach to the sun is seven times farther than Neptune, or 200 astronomical units (AUs). (An AU is the distance between Earth and the sun, about 150 million kilometers.) And Planet X could roam as far as 600 to 1200 AU, well beyond the Kuiper belt, the region of small icy worlds that begins at Neptune's edge about 30 AU.

If Planet X is out there, Brown and Batygin say, astronomers ought to find more objects in telltale orbits, shaped by the pull of the hidden giant. But Brown knows that no one will really believe in the discovery until Planet X itself appears within a telescope viewfinder. "Until there's a direct detection, it's a hypothesis—even a potentially very good hypothesis," he says. The team has time on the one large telescope in Hawaii that is suited for the search, and they hope other astronomers will join in the hunt.

Mene danas da ubiješ ne bih više znao da kažem koliko se "zvanično" računa da ima planeta u našem solarnom sistemu.  :cry: :cry: :cry:

Više mi vrediš živ, i zato da te informišem: bilo je devet, a (za) sada je osam.

To je jer je Pluton ražalovan sa statusa planete, okej. Ali bila je tu i "deseta" planeta pre jedno deset godina  (http://science.nasa.gov/science-news/science-at-nasa/2005/29jul_planetx/)a očigledno nisam upratio šta je s tim bilo...

 Earth Is Made Up Of Two Planets, Say Scientists (http://news.yahoo.com/earth-is-made-up-of-two-planets-say-scientists-154623238.html)

Quote
A 'violent, head-on collision' between Earth and a developing planet called Theia formed the planet that we live on today and also created the moon, according to new research.
A 'planetary embryo' called Theia, thought to be around the same size as Earth or Mars, collided with Earth 4.5 billion years ago with the two being effectively melded together to form a single planet, says the study.
The head-on smash took place approximately 100 million years after the Earth was formed.
While it was already known that the two planets collided, it was previously thought that Theia merely grazed Earth, causing the former to break up, with a piece of the fledgling planet forming the moon.
If that were the case, the moon would have a different chemical composition to Earth because it would be made up predominantly of Theia.
Researchers at the University of California (http://newsroom.ucla.edu/releases/moon-was-produced-by-a-head-on-collision-between-earth-and-a-forming-planet) studied moon rocks brought back to Earth by the Apollo 12, 15 and 17 missions, along with volcanic rocks from the Earth's mantle, found in Hawaii and Arizona.
They found that the rocks from the moon and Earth had almost identical oxygen isotopes, turning the previous theory on its head.
"Theia was thoroughly mixed into both the Earth and the moon, and evenly dispersed between them," said lead researcher Edward Young. "This explains why we don't see a different signature of Theia in the moon versus the Earth."
While Theia ended up incorporated into Earth, Young says that it would probably have become a planet in its own right if the collision hadn't taken place.
The research was published in the journal Science (http://science.sciencemag.org/content/351/6272/493).

Conditions for life may hinge on how fast the universe is expanding (http://www.sciencemag.org/news/2016/02/conditions-life-may-hinge-how-fast-universe-expanding)

Quote
Scientists have known for several years now that stars, galaxies, and almost everything in the universe is moving away from us (and from everything else) at a faster and faster pace. Now, it turns out that the unknown forces behind the rate of this accelerating expansion—a mathematical value called the cosmological constant—may play a previously unexplored role in creating the right conditions for life.
That's the conclusion of a group of physicists who studied the effects of massive cosmic explosions, called gamma ray bursts, on planets. They found that when it comes to growing life, it's better to be far away from your neighbors—and the cosmological constant helps thin out the neighborhood.
"In dense environments, you have many explosions, and you're too close to them," says cosmologist and theoretical physicist Raul Jimenez of the University of Barcelona in Spain and an author on the new study. "It's best to be in the outskirts, or in regions that have not been highly populated by small galaxies—and that's exactly where the Milky Way is."
Jimenez and his team had previously shown that gamma ray bursts could cause mass extinctions (http://www.sciencemag.org/news/2014/11/complex-life-may-be-possible-only-10-all-galaxies) or make planets inhospitable to life by zapping them with radiation and destroying their ozone layer. The bursts channel the radiation into tight beams so powerful that one of them sweeping through a star system could wipe out planets in another galaxy. For their latest work, published this month in Physical Review Letters, they wanted to apply those findings on a broader scale and determine what type of universe would be most likely to support life.
The research is the latest investigation to touch on the so-called anthropic principle: the idea that in some sense the universe is tuned for the emergence of intelligent life. If the forces of nature were much stronger or weaker than physicists observe, proponents note, crucial building blocks of life—such fundamental particles, atoms, or the long-chain molecules needed for the chemistry of life—might not have formed, resulting in a sterile or even completely chaotic universe. Some researchers have tried to gauge how much "wiggle room" various physical constants might have for change before making the cosmos unrecognizable and uninhabitable. Others, however, question what such research really means and whether it is worthwhile.
Jimenez and colleagues tackled one, large-scale facet of the anthropic principle. They used a computer model to run simulations of the universe expanding and accelerating at many different speeds. They then measured how changing the cosmological constant affected the universe's density, paying particular attention to what that meant about gamma ray bursts raining down radiation on stars and planets.
As it turns out, our universe seems to get it just about right (http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.081301). The existing cosmological constant means the rate of expansion is large enough that it minimizes planets' exposure to gamma ray bursts, but small enough to form lots of hydrogen-burning stars around which life can exist. (A faster expansion rate would make it hard for gas clouds to collapse into stars.)
Jimenez says the expansion of the universe played a bigger role in creating habitable worlds than he expected. "It was surprising to me that you do need the cosmological constant to clear out the region and make it more suburbanlike," he says.
Beyond what they reveal about the potential for life in our galaxy and beyond, the findings offer a new nugget of insight into one of the biggest puzzles in cosmology: why the cosmological constant is what it is, says cosmologist Alan Heavens, director of the Imperial Centre for Inference and Cosmology at Imperial College London.
In theory, Heavens explains, either the constant should be hundreds of orders of magnitude higher than it appears to be, or it should be zero, in which case the universe wouldn't accelerate. But this would disagree with what astronomers have observed. "The small—but nonzero—size of the cosmological constant is a real puzzle in cosmology," he says, adding that the research shows the number is consistent with the conditions required for the existence of intelligent life that is capable of observing it.
Lee Smolin, a theoretical physicist at Perimeter Institute for Theoretical Physics in Waterloo, Canada, and a skeptic of the anthropic principle, says the paper's argument is a novel one and that on first reading he didn't see any obvious mistakes. "I've not heard it before, so they're to be praised for making a new argument," he says.
However, he adds, all truly anthropic arguments to date fall back on fallacies or circular reasoning. For example, many tend to cherry-pick by looking only at one variable in the development of life at a time; looking at several variables at once could lead to a different conclusion.
Jimenez says the next step is to investigate whether gamma ray bursts are really as devastating to life as scientists believe. His team's work has shown only that exposure to such massive bursts of radiation would almost certainly peel away a planet's protective ozone layer.  "Is this going to be catastrophic to life?" he says. "I think so, but it may be that life is more resilient than we think."

Astronomers say they've found the biggest structure in the universe and they named it the BOSS (https://www.washingtonpost.com/news/morning-mix/wp/2016/03/11/astronomers-say-theyve-found-the-biggest-structure-in-the-universe-and-they-named-it-the-boss/)

Quote
You think the Milky Way (shown here in the night sky over the German island of Fehmarn) is big? Pfft. Wait till you hear about the BOSS Great Wall. (Daniel Reinhardt/European Pressphoto Agency)
The BOSS is big. Really big. Yuuuuuge.

So big that when a star is born on one side of the BOSS, it takes a billion years for the light to reach the other side.

So big that comparing the BOSS to the next biggest thing like it is like comparing Andre the Giant to your 3-year-old nephew.

What is the BOSS? It's a wall. A Great Wall. It makes other walls — you know which ones — look like, well, nothing, because the BOSS Great Wall is an immense complex comprising more than 800 galaxies and weighing 10,000 times as much as the Milky Way and other walls are just a measly pile of rocks on an insignificant planet in a remote part of space.

(Astronomers, here to put human affairs in perspective since 1564 (https://www.google.com/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=galileo+birthday).)
  This animated flight through the universe shows close to 400,000 galaxies. (Berkeley Lab) 
Anyway, scientists working for the Baryon Oscillation Spectroscopic Survey (http://www.sdss3.org/surveys/boss.php) — the international galaxy-mapping effort from which the BOSS gets its truly spectacular acronym — say that the newly discovered cosmic feature is the largest structure in the universe. Or at least, as much of the universe as they've mapped so far.

In a study published in the newest issue of the journal Astronomy and Astrophysics (http://arxiv.org/pdf/1602.08498v1.pdf), the scientists describe the BOSS Great Wall (BGW) as an enormous collection of galaxies more than one billion light-years across.

"It was so much bigger than anything else in this volume," Heidi Lietzen (http://vivaldi.ll.iac.es/severoochoa/index.php/people/postdoctoral-fellows) of the Canary Islands Institute of Astrophysics, a lead author on the study, told the New Scientist (https://www.newscientist.com/article/2079986-billion-light-year-galactic-wall-may-be-largest-object-in-cosmos/).

[Astronomers just saw farther back in time than they ever have before (http://wpo.st/KVqK1)]

"Walls" like the BGW are part of the underlying structure of the universe. Most of space is a vast empty void, and all the stuff that astronomers look for — stars, planets, the galaxies they constitute — is threaded through that nothingness. Pulled together by gravity, galaxies coalesce into clusters, which in turn form larger structures called superclusters, as explained by PBS (http://www.pbs.org/wgbh/nova/universe/tour_ggs.html). Those are then corralled into "walls" — the coronary arteries of this giant system of matter, and the biggest things in space.

Researchers for the Sloan Digital Sky Survey (the BOSS survey is one of its projects) have been trying to map that web in order to better understand the universe's history, size and speed of expansion. Using a dedicated telescope located in the remote desert scrubland of Sunspot, N.M., they scan huge swaths of the sky for distant galaxies, brilliant quasars and other celestial objects.

In the process, they've found some pretty enormous things. Like the "Sloan Great Wall (http://apod.nasa.gov/apod/ap071107.html)," which Lietzen and her co-authors say is the closest system of superclusters comparable to the BGW.

But even that is dwarfed by the Sloan survey's newest find. The BOSS Great Wall has ten times the volume of the Sloan wall and is almost 70 percent larger in diameter. It comprises four superclusters containing 830 galaxies, and it looms in space some 5 billion light-years away from Earth. (For what it's worth, the biggest thing in our neck of the woods, the Laniakea supercluster (https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwjR5InckLjLAhVJOiYKHeOjBWkQFggcMAA&url=https%3A%2F%2Fpublic.nrao.edu%2Fnews%2Fpressreleases%2Fsupercluster-gbt&usg=AFQjCNHKVdMWwWUUmm1f852BSAPSgtdplA&sig2=2uRqg2E4PFjLnwCk1rVIMg&bvm=bv.116573086,d.eWE) that includes our own Milky Way galaxy, is less than half the size of the BGW.)

['Touchdown!' Scott Kelly returns to Earth with a fist-pump and a cult following (http://wpo.st/YVqK1)]

Indeed, the BGW is so big that some scientists question whether it can really be considered all one thing.

"I don't entirely understand why they are connecting all of these features together to call them a single structure," Allison Coil (http://cass.ucsd.edu/~acoil/home.html), an astrophysicist at the University of California at San Diego, told the New Scientist (https://www.newscientist.com/article/2079986-billion-light-year-galactic-wall-may-be-largest-object-in-cosmos/). "There are clearly kinks and bends in this structure that don't exist, for example, in the Sloan Great Wall."

But size isn't really the point, Smithsonian Magazine (http://www.smithsonianmag.com/smart-news/meet-boss-largest-structure-universe-180958378/) noted. The discovery of the BOSS Great Wall is just one part of a larger survey that will — astronomers hope — reveal not just what the universe looks like, but how it's evolved and how it continues to change.

Which is a very nice sentiment. But the BOSS Great Wall is still biggest. And you know what that makes it?

A winner.

Astronomers discovered unexpected activity on a giant asteroid that could point to something huge (http://finance.yahoo.com/news/something-unexpected-happening-those-mysterious-163417488.html)

Quote
Nestled 250 million miles from Earth, between the orbits of Mars and Jupiter, is the largest object in the asteroid belt: Ceres.
It's home to some of the most puzzling features ever observed in our solar system, including a giant pyramid that dwarfs many mountains on Earth and several dazzling bright spots inside a 50-mile-wide crater.
Now, recent research, led by astronomers at the INAF-Trieste Astronomical Observatory (http://www.oats.inaf.it/) in Italy, has discovered that these unique bright spots are doing something unexpected: They're changing.
And it could point to some of the most compelling evidence yet for a huge underground ocean sloshing beneath Ceres' rocky shell.A misty glowWe first got a good look at Ceres and its perplexing landscape last year, when the Dawn spacecraft fell into orbit around it. But Dawn isn't the only instrument scientists are using to study Ceres.
Using the European Southern Observatory's 3.6-meter telescope, the team noticed that Ceres' spots appear to vary in brightness over time — growing brighter before dimming back down, like a lightning bug on a summer night.
Interestingly, the spots are brightest when they're on the day side of Ceres, facing the sun. This has led the team to suspect that these surprising changes are the result of sublimation, when a solid becomes a gas.
Heat from the sun's light sublimates certain materials, which then forms a visible misty haze above the spots, the team reported (http://www.oats.inaf.it/index.php/it/pubbliche-relazioni/news/602-foschia-su-cerere.html) in the Monthly Notices of the Royal Astronomical Society (http://www.eso.org/public/archives/releases/sciencepapers/eso1609/eso1609a.pdf).
When additional sunlight then strikes the mist, it scatters the light, giving off a brilliant glow that makes the spots appear brighter.
The mist, however, is only temporary. It seems to evaporate within a few hours after forming. Without any mist hanging over them, the spots then appear to dim, which explains the variable changes the team observed.
But there's one thing the mist doesn't explain: What's fueling it in the first place.
(NASA/ESA)
A grand ocean in spaceCeres has been around since the start of our solar system, which makes it roughly 4.6 billion years old.
If these spots have been shooting off mist for that long, then they should have disappeared by now, unless some source was continuously supplying the material.
So what's going on?
The team suspects that a vast underground ocean could be swelling up through cracks in Ceres' crust, which formed after a powerful impact.
"It is assumed that something comes out from [the] interior of the planet where there is a large amount of water and that can evaporate filling the crater and eventually dispersed under the action of solar radiation," the team said in a press release (http://www.oats.inaf.it/index.php/it/pubbliche-relazioni/news/602-foschia-su-cerere.html).
If there's liquid water underneath Ceres' surface, then that means that there must also be a heat source.
Ceres is turning out to be a far more interesting world than we thought.

Još priče o devetoj planeti...

  Our solar system may have a ninth planet after all — but not all evidence is in  (http://www.theverge.com/2016/1/20/10801824/ninth-planet-x-discovered-evidence)

Bio je Tajson kod Kolbera pre neki mesec da objašnjava matematiku glede toga...

What Is Dark Matter? Astronomers Are One Step Closer to Understanding Mysterious Phenomena (http://mic.com/articles/139082/what-is-dark-matter-astronomers-are-one-step-closer-to-understanding-mysterious-phenomena#.cCSOYCYiG)

Quote

Astronomers may have detected signatures of elusive dark matter (http://home.cern/about/physics/dark-matter) — a mysterious, invisible material that permeates the universe, but has so far proved undetectable. 

If the results are confirmed, scientists will have a better idea of what dark matter is and how we might be able to directly observe it.

Even though we can't see dark matter, we know it exists because we can measure its gravitational effect on visible matter. Galaxies in our observable universe are rotating way too fast (http://home.cern/about/physics/dark-matter) for the gravity of their visible matter to be enough to hold them together. Based on the matter we can see, these galaxies should have flown apart and dissolved long ago.

So, clearly, something else is helping hold these galaxies together — and astronomers think that something is the gravitational pull of dark matter. In fact, astronomers estimate the matter we can see makes up only about 5% (http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/) of the universe, while dark matter makes up 27% (http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/). (The other 68% is tied up in something called dark energy.)

Detecting dark matter: One of the most popular dark matter theories is that it is composed of weakly interacting massive particles (http://imagine.gsfc.nasa.gov/educators/galaxies/imagine/dark_matter.html), or WIMPs, that annihilate each other when they collide. Those collisions should create a type of detectable high-energy radiation in the form of gamma rays.

A team of astronomers studying the distribution of gamma ray emissions near the center of the Milky Way found (http://arxiv.org/abs/1402.6703) a huge gamma ray burst signature that might be evidence of such dark matter collisions.
The astronomers acknowledge it's possible the gamma ray burst came from a nearby group of rotating neutron stars called pulsars. But after the team pinned down more specific locations for the gamma rays and mapped out the emissions in greater detail, it seems more likely they came form dark matter collisions than pulsars.

"The team was able to show with high significance that the distribution of gamma-ray emission is in good agreement with the predictions of simple annihilating dark matter models, but less likely to be consistent with a pulsar explanation," the Smithsonian Astrophysical Observatory explained in a statement (https://www.cfa.harvard.edu/news/su201612) about the research.

If the results are confirmed, it will lend a lot of support to the WIMP theory and it could help us finally directly detect dark matter.

Večeras sam otkrila ovaj kanal. I ne mogu da prestanem da ga gledam:

http://www.youtube.com/watch?v=ZL4yYHdDSWs

First Water Clouds Reported outside the Solar System (http://www.scientificamerican.com/article/first-water-clouds-reported-outside-the-solar-system/)

Quote
Signs seen on brown dwarf, an object bigger than a planet and smaller than a star




For the first time ever, astronomers have found strong evidence of water clouds on a body outside the solar system.
New observations of a frigid object called WISE 0855, which lies 7.2 light-years from Earth, suggest that the "failed star" has clouds of water, or water ice, in its atmosphere, the researchers said.
"We would expect an object that cold to have water clouds, and this is the best evidence that it does," study lead author Andrew Skemer, an assistant professor of astronomy and astrophysics at the University of California, Santa Cruz, said in a statement (http://news.ucsc.edu/2016/07/coldest-brown-dwarf.html) released by the university. [Frigid Brown Dwarf May Have Water-Ice Clouds (Video) (http://www.space.com/27103-frigid-brown-dwarf-may-have-water-ice-clouds-video.html)]
WISE 0855 is five times more massive than Jupiter, making it a brown dwarf (http://www.space.com/24467-brown-dwarfs-failed-stars-explained-infographic.html)—an object too large to be a planet but too small to spark the internal fusion reactions that power stars (a fact that explains another name for these bodies: "failed stars").
Scientists discovered WISE 0855 in 2014, using data from NASA's Wide-field Infrared Survey Explorer (WISE) spacecraft. A later paper in 2014 (co-authored by Skemer) uncovered some evidence of water clouds in the object's atmosphere, based on limited photometric data (how bright the object is in specific light wavelengths).
In the new study, Skemer and his colleagues used the Gemini North telescope in Hawaii to study the brown dwarf for 13 nights. Gemini North is located on the highest Hawaiian mountain (Mauna Kea), at an altitude with little water vapor to interfere with telescopic observations.
These observations allowed the astronomers to make the first spectroscopy (light fingerprint) measurements of WISE 0855. The team found water vapor and also confirmed the object's temperature, which is about minus 10 degrees Fahrenheit (minus 23 degrees Celsius, or 250 kelvins). For comparison, the temperature at the top of Jupiter's clouds is about minus 225 degrees Fahrenheit (minus 143 degrees Celsius, or 130 kelvins).
WISE 0855 is "five times fainter than any other object detected with ground-based spectroscopy at this wavelength," Skemer said in a different statement (http://www.gemini.edu/node/12536). "Now that we have a spectrum, we can really start thinking about what's going on in this object. Our spectrum shows that WISE 0855 is dominated by water vapor and clouds, with an overall appearance that is strikingly similar to Jupiter."
Specifically, the spectrum of WISE 0855 appears very similar to the water-absorption features found in Jupiter's atmosphere. But there also are some differences, such as the amount of phosphine (a compound of phosphorous and hydrogen): Jupiter has a lot of it; WISE 0855 does not.
Phosphine is created in the scalding-hot interiors of objects, so its presence in an atmospheric spectrum suggests that a lot of mixing has gone on. So, based on phosphine concentrations, it appears that Jupiter's atmosphere is much more turbulent than that of WISE 0855, study team members said.
The new research was published in The Astrophysical Journal Letters.

   
• Nearest Brown Dwarf Star Shows Moody Atmosphere | Video (http://www.space.com/24462-nearest-brown-dwarf-star-shows-moody-atmosphere-video.html)
• WISE Up: Space Photos from NASA's Sky-Mapping Telescope (http://www.space.com/10894-wise-great-photos-nasa-sky-mapping-telescope.html)
• Photos: Jupiter, the Solar System's Largest Planet (http://www.space.com/11682-photos-jupiter-largest-planet-solar-system.html)

 New Dwarf Planet Discovered in Outer Solar System  (http://www.seeker.com/new-dwarf-planet-discovered-in-outer-solar-system-1915913544.html)

QuoteAstronomers have spotted another dwarf planet, 435 miles in diameter, beyond the orbit of Neptune.


Astronomers have found another Pluto-like dwarf planet (http://www.seeker.com/tag/dwarf-planet) located about 20 times farther away from the sun than Neptune.
The small planet, designated 2015 RR245, is estimated to be about 435 miles in diameter and flying in an elliptical, 700-year orbit around the sun.
RELATED: Weird Dark Moon Orbiting Dwarf Planet Makemake (http://www.seeker.com/weird-dark-moon-orbiting-dwarf-planet-makemake-1888690309.html)

At closest approach, RR245 will be about 3.1 billion miles from the sun, a milestone it is expected to next reach in 2096.
At its most distant point, the icy world is located about 7.5 billion miles away.
It was found by a joint team of astronomers using the Canada-France-Hawaii Telescope (CFHT) on Maunakea, Hawaii, in images taken in September 2015 and analyzed in February. The discovery was announced on Monday in the Minor Planet Electronic Circular.

"There it was on the screen -- this dot of light moving so slowly that it had to be at least twice as far as Neptune from the sun," Michele Bannister, a postdoctoral fellow with the University of Victoria in British Columbia, said in a press release.

RELATED: The Hunt for Planet Nine: What's It Made Of? (http://www.seeker.com/the-hunt-for-planet-nine-whats-it-made-of-1771180210.html)
The Minor Planet Center describes RR245 as the 18th largest object in the Kuiper Belt (http://www.seeker.com/tag/Kuiper-Belt).

"The vast majority of the dwarf planets like RR245 were destroyed or thrown from the solar system in the chaos that ensued as the giant planets moved out to their present positions," the CFHT said. "RR245 is one of the few dwarf planets that has survived to the present day — along with Pluto and Eris, the largest known dwarf planets."
Observations of RR245 will continue. Once its precise orbit is known the dwarf planet will get an official name. As discoverers, the Outer Solar System Origins Survey team has naming rights.

World's Most Powerful Radio Telescope Discovers 1300 New Galaxies in Trial Run (http://motherboard.vice.com/read/worlds-most-powerful-radio-telescope-discovers-1300-new-galaxies-in-trial-run)

Quote
On Saturday night astronomers at the South African MeerKAT radio telescope array (http://www.ska.ac.za/meerkat/) fired up 16 of its recently completed dishes and released the first ever image from what is slated to become the world's most powerful radio telescope. The initial results were incredibly promising: operating with only one quarter of the 64 dishes that will eventually comprise MeerKAT, the telescope was able to find 1300 galaxies in a small corner of the universe where only 70 galaxies were known to exist previously.


MeerKAT, which is located roughly 350 miles north of Cape Town, is something of a proof of concept for the Square Kilometer Array (https://www.skatelescope.org/) (SKA) which is slated to come online in the 2020s. When the 3000 dishes that comprise SKA go live they will comprise the most sensitive radio telescope in the world, but for now this illustrious title will be claimed by MeerKAT, whose 64 dishes will be incorporated into the SKA array when they're finished next year.
Even operating with only a quarter of its eventual 64 dishes, MeerKAT's Saturday evening trial run established the radio telescope as the most powerful in the southern hemisphere according to SKA's chief scientist (https://www.theguardian.com/science/2016/jul/17/first-image-from-south-african-super-radio-telescope-far-better-than-expected) Fernando Camilo. By the time all 64 dishes are completed next year, Camilo claimed MeerKAT will be the most powerful telescope in the world.
As one of the two main clusters of radio telescopes comprising SKA (the other cluster is located in Australia), MeerKAT will help astronomers study everything from black holes and dark energy to the development of the early universe some 13 billion years ago. The first image from MeerKAT depicts several galaxies with massive black holes at their center, as well as a galaxy that is roughly 200 million light years away.
Scientists and astronomers are already chomping at the bit to get a chance to put this powerful tool to use, and nearly 500 scientific groups from over 40 countries have booked time on the telescope between now and 2022.

 Curious tilt of the Sun traced to undiscovered planet (http://www.spacedaily.com/reports/Curious_tilt_of_the_Sun_traced_to_undiscovered_planet_999.html)

QuotePlanet Nine - the undiscovered planet at the edge of the solar system that was predicted by the work of Caltech's Konstantin Batygin and Mike Brown in January 2016 - appears to be responsible for the unusual tilt of the Sun, according to a new study. The large and distant planet may be adding a wobble to the solar system, giving the appearance that the Sun is tilted slightly.
"Because Planet Nine is so massive and has an orbit tilted compared to the other planets, the solar system has no choice but to slowly twist out of alignment," says Elizabeth Bailey, a graduate student at Caltech and lead author of a study announcing the discovery.
All of the planets orbit in a flat plane with respect to the Sun, roughly within a couple degrees of each other. That plane, however, rotates at a six-degree tilt with respect to the Sun - giving the appearance that the Sun itself is cocked off at an angle. Until now, no one had found a compelling explanation to produce such an effect.
"It's such a deep-rooted mystery and so difficult to explain that people just don't talk about it," says Brown, the Richard and Barbara Rosenberg Professor of Planetary Astronomy.
Brown and Batygin's discovery of evidence that the Sun is orbited by an as-yet-unseen planet - that is about 10 times the size of Earth with an orbit that is about 20 times farther from the Sun on average than Neptune's - changes the physics.
Planet Nine, based on their calculations, appears to orbit at about 30 degrees off from the other planets' orbital plane - in the process, influencing the orbit of a large population of objects in the Kuiper Belt, which is how Brown and Batygin came to suspect a planet existed there in the first place.
"It continues to amaze us; every time we look carefully we continue to find that Planet Nine explains something about the solar system that had long been a mystery," says Batygin, an assistant professor of planetary science.
Their findings have been accepted for publication in an upcoming issue of the Astrophysical Journal, and will be presented this week at the American Astronomical Society's Division for Planetary Sciences 48th annual meeting, held jointly in Pasadena, California, with the 11th European Planetary Science Congress.
The tilt of the solar system's orbital plane has long befuddled astronomers because of the way the planets formed: as a spinning cloud slowly collapsing first into a disk and then into objects orbiting a central star.
Planet Nine's angular momentum is having an outsized impact on the solar system based on its location and size. A planet's angular momentum equals the mass of an object multiplied by its distance from the Sun, and corresponds with the force that the planet exerts on the overall system's spin. Because the other planets in the solar system all exist along a flat plane, their angular momentum works to keep the whole disk spinning smoothly.
Planet Nine's unusual orbit, however, adds a multi-billion-year wobble to that system. Mathematically, given the hypothesized size and distance of Planet Nine, a six-degree tilt fits perfectly, Brown says.
The next question, then, is how did Planet Nine achieve its unusual orbit? Though that remains to be determined, Batygin suggests that the planet may have been ejected from the neighborhood of the gas giants by Jupiter, or perhaps may have been influenced by the gravitational pull of other stellar bodies in the solar system's extreme past.
For now, Brown and Batygin continue to work with colleagues throughout the world to search the night sky for signs of Planet Nine along the path they predicted in January. That search, Brown says, may take three years or more.
"Solar Obliquity Induced by Planet Nine," (https://arxiv.org/abs/1607.03963) Elizabeth Bailey, Konstantin Batygin and Michael E. Brown, 2016, Astrophysical Journal

The supermoon (perigee full moon) on November 14, 2016, will bring the moon closer to Earth than it has been since January 26, 1948. What's more, the moon won't come this close to Earth again until November 25, 2034. That makes the November 2016 full moon the closest and largest supermoon in a period of 86 years!

  Stephen Hawking Puts An Expiry Date On Humanity (https://www.yahoo.com/news/stephen-hawking-puts-expiry-date-103124525.html) 

Quote
Stephen Hawking believes that humanity has less than a thousand years on Earth before a mass extinction occurs, the leading theoretical physicist said during a speech Tuesday at Oxford University Union, U.K.
According to Hawking, the only way humans can avoid the possibility of extinction was to find another planet to inhabit. At the talk (http://www.express.co.uk/news/science/732606/Stephen-Hawking-end-of-the-world), Hawking gave a one-hour speech on man's understanding of the origin of the universe from primordial creation myths to the most cutting-edge predictions made by "M-theory," which presents an idea about the basic substance of the universe.
"We must also continue to go into space for the future of humanity," he said. "I don't think we will survive another 1000 without escaping beyond our fragile planet."
Earlier this year, the 74-year-old predicted that technology would lead Earth to a virtually inevitable global cataclysm.
"We face a number of threats to our survival from nuclear war, catastrophic global warming, and genetically engineered viruses," he said in January. "The number is likely to increase in the future, with the development of new technologies, and new ways things can go wrong. Although the chance of a disaster to planet Earth in a given year may be quite low, it adds up over time."
Hawking reportedly added that finding another planet was the only chance of survival.
"[We] have spread out into space, and to other stars, so a disaster on Earth would not mean the end of the human race," he said. "However, we will not establish self-sustaining colonies in space for at least the next hundred years, so we have to be very careful in this period."
Since 2009, NASA has been working to discover Earth-like planets that can support life.
The discovery (https://www.nasa.gov/kepler/discoveries) of more than 2,000 planets has been confirmed so far and over 4,500 "planet candidates" are waiting to have their existence confirmed.
"The first exoplanet orbiting another star like our sun was discovered in 1995," according to NASA (http://www.nasa.gov/press-release/nasa-hosts-media-teleconference-to-announce-latest-kepler-discoveries/). "Exoplanets, especially small Earth-size worlds, belonged within the realm of science fiction just 21 years ago. Today, and thousands of discoveries later, astronomers are on the cusp of finding something people have dreamt about for thousands of years."

Овај би да побјегне од Трампа! Неће моћи!

Quote from: Meho Krljic on 21-01-2016, 13:00:53
To je jer je Pluton ražalovan sa statusa planete

 NASA Scientists Have Proposed a New Definition of Planets, and Pluto Could Soon Be Back  (http://www.sciencealert.com/nasa-scientists-have-proposed-a-new-definition-for-planets-and-it-could-change-everything)

 Astronomers Just Found a Star Orbiting a Black Hole at 1 Percent the Speed of Light  (http://www.sciencealert.com/astronomers-just-found-a-star-orbiting-a-black-hole-at-1-percent-the-speed-of-light)

Quote
  Astronomers have just spotted a star whizzing around a vast black hole at about 2.5 times the distance between Earth and the Moon, and it takes only half an hour to complete one orbit.
To put that into perspective, it takes roughly 28 days for our Moon to do a single lap around our relatively tiny planet at speeds of 3,683 kilometres (2,288 miles) per hour, meaning this star is moving at some mind-boggling, break-neck speeds. Using data from an array of deep space telescopes, a team of astronomers have measured the X-rays pouring from a binary star system called 47 Tuc X9, which sits in a cluster of stars about 14,800 light-years away.
The pair of stars aren't new to astronomers - they were identified (https://arxiv.org/pdf/1702.02167.pdf) as a binary system way back in 1989 - but it's now finally becoming clear what's actually going on here.
"For a long time, it was thought that X9 is made up of a white dwarf pulling matter from a low mass Sun-like star," said researcher Arash Bahramian (http://chandra.harvard.edu/blog/node/637).
When a white dwarf pulls material from another star, the system is described as a cataclysmic variable star (https://en.wikipedia.org/wiki/Cataclysmic_variable_star). But back in 2015 (http://chandra.harvard.edu/press/17_releases/press_031317.html), one of the objects was found to be a black hole, throwing that hypothesis into serious doubt.
Data from Chandra has confirmed large amounts of oxygen in the pair's neighbourhood, which is commonly associated with white dwarf stars. But instead of a white dwarf ripping apart another star, it now seems to be a black hole stripping the gases from a white dwarf.
White dwarfs (https://en.wikipedia.org/wiki/White_dwarf) are super dense objects that are usually the remnants of a star - think of something with the mass of our Sun but only as big as our planet - so pulling material from its surface would require some impressive gravity. "We think the star may have been losing gas to the black hole for tens of millions of years and by now has now lost the majority of its mass," said researcher James Miller-Jones (http://www.icrar.org/whitedwarf/) from Curtin University and the International Centre for Radio Astronomy Research.
The real exciting news, however, is regular changes in the X-rays' intensity suggest this white dwarf takes just 28 minutes to complete an orbit, making it the current champion of cataclysmic dirty dancers.
"Prior to this discovery, the closest star around any likely black hole was a system known as MAXI J1659-152, which is in an orbit with a 2.4-hour period," said Miller-Jones (http://www.sciencealert.com/Prior%20to%20this%20discovery,%20the%20closest%20star%20around%20any%20likely%20black%20hole%20was%20a%20system%20known%20as%20MAXI%20J1659-152,%20which%20is%20in%20an%20orbit%20with%20a%202.4-hour%20period.%20If%20the%20likely%20black%20holes%20in%20both%20systems%20have%20similar%20masses,%20this%20would%20imply%20an%20orbit%20three%20times%20larger%20in%20physical%20size%20than%20the%20one%20we%20found%20in%20X9.).
"If the likely black holes in both systems have similar masses, this would imply an orbit three times larger in physical size than the one we found in X9."
To put it in perspective, the distance between the two objects in X9 is about 1 million kilometres (about 600,000 miles), or about 2.5 times the distance (http://chandra.harvard.edu/press/17_releases/press_031317.html) from here to the Moon.
Crunching the numbers, that's a journey of roughly 6.3 million kilometres (about 4 million miles) in half an hour, giving us a speed of 12,600,000 km/hr (8,000,000 miles/hr) - about 1 percent of the speed of light.
"Finding these rare black holes is important, as they are not only the end points of massive stars, produced in supernova explosions, they also continue to play a role in the evolution of other stars after their deaths," Geraint Lewis from the University of Sydney (http://www.smh.com.au/technology/sci-tech/white-dwarf-x9-is-closest-star-found-orbiting-a-black-hole-at-astonishing-12-million-kmh-20170314-guxh1d.html) told Marcus Strom at The Sydney Morning Herald.
Our two star-crossed lovers aren't fated to collapse into each other's arms any time soon, at least, with the dance looking like it will continue without the white dwarf falling into the black hole or being ripped apart.
In fact, if anything, it seems the two objects were even closer together in the past and orbiting even faster.
For the black hole to overcome the white dwarf's own intense gravity, the bodies need to be fairly close together. Over time, as material is stripped away, the now-lighter white dwarf would slip a little further back.
"Eventually so much matter may be pulled away from the white dwarf that it ends up only having the mass of a planet," said researcher Craig Heinke (http://chandra.harvard.edu/press/17_releases/press_031317.html). "If it keeps losing mass, the white dwarf may completely evaporate."
That's good news for future scientists keen to study gravitational waves; while the current technology used by the Laser Interferometer Gravitational-Wave Observatory isn't able to spot the slow pulses emitted by X9, it's not out of the question that progress in that field will one day allow us to detect lower frequency waves.
Of course, by then we might have found a new king and queen of cataclysmic variable stars, spinning the night away at even faster speeds.
This research has been published in the Monthly Notices of the Royal Astronomical Society (https://academic.oup.com/mnras/article/3052451/The)and you can read it in full at arXiv.org (https://arxiv.org/pdf/1702.02167.pdf).
   

Quote from: Meho Krljic on 25-02-2017, 06:35:52

Quote from: Meho Krljic on 21-01-2016, 13:00:53
To je jer je Pluton ražalovan sa statusa planete

 NASA Scientists Have Proposed a New Definition of Planets, and Pluto Could Soon Be Back  (http://www.sciencealert.com/nasa-scientists-have-proposed-a-new-definition-for-planets-and-it-could-change-everything)

A kako se i lepo kaže na američkom: kada kiši onda poliva:


A new definition would add 102 planets to our solar system — including Pluto (https://www.washingtonpost.com/news/speaking-of-science/wp/2017/03/20/a-new-definition-would-add-102-planets-to-our-solar-system-including-pluto/?utm_term=.bbb1416acb4e)

Odgovor na pitanje iz naslova je, kako nas uči Beteridž, "ne", ali svejedno, ovo je zanimljivo:

Multiverse: have astronomers found evidence of parallel universes?  (https://www.theguardian.com/science/across-the-universe/2017/may/17/multiverse-have-astronomers-found-evidence-of-parallel-universes)

China built the world's largest telescope, but has no one to run it (https://arstechnica.com/science/2017/08/china-built-the-worlds-largest-telescope-but-has-no-one-to-run-it/)

Podignite pogled ka noćnom nebu i uživajte!

Quote
Pripremite se, za 2 dana počinje nebeski spektakl

Podignite pogled ka noćnom nebu i uživajte!

Kao i svakog leta, i ovog ćemo moći da uživano u meteorskoj kiši Perseida.

Ovaj događ poseban je kada se radi o meteoriskim kišama, pošto Perseidi imaju kudikamo veći intenzitet od drugih, pa prosečno za sat vremena može da se vidi i do 80 meteora koji sagorevaju u atmosferi.

Perseidi su ostaci komete 109 P/Swift-Tuttle koja oko nama najbliže zvezde, odnosno Sunca, orbitira jednom 133 godine Otkrivena je daleke 1862. godine.

Zemlja svake godine prolazi kroz ostatke te komete, pa tada dolazi do pojave meteorske kiše Perseida.

Ove godine će najveći broj "zvezda padalica" biti vidljiv u noći 12/13. avgusta. Problem mogu da prave Mesec, koji će biti 73 odsto obasjan Suncem, kao i eventualni oblaci.

Najbolje vreme za posmatranje nema biće posle 22 sata 12. avgusta, a idealno oko dva sata posle ponoći.

Ukoliko želite da uživate u ovom nebeskom spektaklu, najbolje bi bilo da se odmaknete od Beograda i drugih većih gradova u Srbiji, odnosno, ako je ikako moguće, da odete na neku planinu, gde nema svetlosnog zagađenja i gde je nebo kudikamo čistije, s većim brojem zvezda na nebu.

http://webtribune.rs/pripremite-se-za-2-dana-pocinje-nebeski-spektakl/

Half the universe's missing matter has just been finally found (https://www.newscientist.com/article/2149742-half-the-universes-missing-matter-has-just-been-finally-found/amp/)

Pa... da sačekamo 16. Oktobar onda....


Mystery Space Announcement: Scientists to Reveal Astronomical Phenomenon 'Never Witnessed Before' (http://www.newsweek.com/gravitational-waves-mystery-announcement-astronomical-phenomenon-682561)

neutron star collision. :roll:

Zapravo da.

Astronomers just measured a whole lot more than gravitational waves (https://www.engadget.com/2017/10/16/astronomers-measured-more-than-gravitational-waves/) 


    Scientists witness huge cosmic crash, find origins of gold (http://www.sfgate.com/news/science/article/Scientists-witness-huge-cosmic-crash-find-12281190.php)

Može jedno pitanje u vezi astronomije/astrofizike?

Pošto ja sve to smatram za okultno zavarivanje ,obmanjivanje i utupljivanje ljudske vrste od strane hajskul maltretiranih cvikeraša koji ionako imaju više sajbersexa nego realnog, jer su ih ovi drugi maltretirali ceo teen period jelte, želim odgovor od onih koji ne razmišljaju kao ja.

Koji će nam konkretan s' oproštenjem kurats sve te gluposti koje oni baljezgaju?
I crne rupe, i kohezije i anhezije planeta, talasa, trista PMaterina, koje imaju istu svrhu kao Alisa u zemlji čuda...
bezveznu, apstraktnu razonodu.
Koji je konkretno benefit ljucke vrste od svega toga?

Teflon.


A ima i drugih benefita:

https://spinoff.nasa.gov/Spinoff2008/tech_benefits.html

https://www.nasa.gov/50th/50th_magazine/benefits.html

https://www.universetoday.com/37079/benefits-of-space-exploration/

Teflon su smislili metalurzi, hemičari, kovači, metaloglodači,strugari,bravari.
Nema veze astro-fizika sa teflonom.

Ako će ovi tvoji linkovi da mi objasne samo kako su amerikanci otvorili masu novih fabrika i givdpipldžaaaaabz' i pospešili throvavejsosajiti na konto slogana, idemo na mars,
onda je sve jedna još veća lagarija i ja tu ne vidim benefit.
Da je benefit, Srbija ne bi popila bombe i Ameri bi imali kule bliznakinje, zajebi.
Bajdvej, i sve te ostale STVARI koje su NAPRAVILE druge grane NAUKE, nemaju veze sa astronomijom a ni astrofizikom...

Vidim da te nisu zadovoljili. 'Oćeš kratku priču, novelu, roman ili pentologiju?

Kratko, konkretno i jebitačno!
Ništa te suviše pakovane i lepo zamotane, pa unutra mućak!

Naslušah se za života govorancija, parola i manifesta, ne zna se koji okultniji.

Ne zna se unapred šta nam konkretno korisno može doneti znanje o postojanju crnih rupa. Ali bolje da ulažemo u to znanje nego u još ubitačnije projektile i još čudesnije načine da naudimo jedni drugima.

U nekoj jakoj dalekoj budućnosti možda će nam recimo zatrebati zlata u masi jednakoj masi cele jedne planete. Pošto sada imamo jako dobru predstavu da zlato nastaje u sudaru dve neutronske zvezde (NAUKA) onda sve što treba da uradimo je da odemo do jednog takvog sudara i pokupimo svo to zlato koje prosto stoji tamo i čeka da bude pokupljeno.


EDIT: Uzgred, sad skoro nas je mimoišao asteroid veličine kuće (http://bgr.com/2017/10/14/asteroid-tc4-hitting-earth-future-2079/). ASTRONOMI su izračunali da sledeći susret sa istim asteroidom 2050. godine neće biti opasan, ali trenutno ne mogu ništa da garantuju za susret posle toga 2079. godine. Treba im više podataka, to jest više ulaganja u ASTRONOMIJU.

U početku bejaše reč... e, čovek je radoznala živuljka pa bi da zna i šta je na kraju.


Istraživanja se finansiraju jer sva naučna i tehnička istraživanja imaju nuzprodukte kroz koje stiže novo finansiranje. Da dam primere? I teflon je... Dobro, neću.


Najbogatiji daju pare da saznaju mogu li i gde da zbrišu, kad dara prevrši meru.


Od viška pameti može da zaboli glava, ali od manjka je još gore.

Ako nam je pamet dotle stigla da su nam vodilje imaginarne crne rupe i hipotetički promašaji asteroida, svaka nam čast, zaslužujemo da budemo tu gde jesmo.

Meho da lupa glavu šta će sa jadnim starcima, ja da crtam haj fantazi sa goblinima a scallop da se nakucava sa nama dvojicom.

Da budemo fer, naravno da nije ni očigledno ni intuitivno šta normalan svet dobija time što neki tamo gledaju kroz teleskope u nebo i piskaraju neke svoje naučne radove. Možda bi zgodna paralela bila sa nekadašnjim istraživanjem mora i oceana gde su se isto ljudi bavili naukom koja nije odmah mogla da da jasne korisne rezultate. Ali, eto, drndali su ljudi te svoje tadašnje astronomije i geometrije i kada je na kraju napravljen sekstant, odjednom su brodovi mogli da se otiskuju dalje od obale i da se zalete preko mora i naprave mnoga korisna otkrića koja su se isplatila svežim resursima, trgovačkim rutama itd. Naravno, nemamo pojma šta i kako će biti, ako ga bude, korist od sadašnjih astronomskih istraživanja, ali nije sasvim iracionalno nadati se sličnim prodorima...

Quote from: Ugly MF on 17-10-2017, 13:10:10

Meho da lupa glavu šta će sa jadnim starcima, ja da crtam haj fantazi sa goblinima a scallop da se nakucava sa nama dvojicom.

Eto nuzprodukta fajde od crnih rupa i promašaja asteroida. Uroš našao model povremenog nelupanja glavom zbog staraca, ti ne moraš da misliš dok crtaš gobline, a ja kompletiram likove za neko sledeće pisanije.

Mnjeeeeee....
Ni Mehovi starci ,ni moji goblini, ni tvoj sajfaj nemaju ama baš nikakve veze sa astrofizikom.
To smo se zajebavali, ajmo dalje.

Quote from: Ugly MF on 17-10-2017, 11:37:13
...
Koji će nam konkretan s' oproštenjem kurats sve te gluposti koje oni baljezgaju?
I crne rupe, i kohezije i anhezije planeta, talasa, trista PMaterina, koje imaju istu svrhu kao Alisa u zemlji čuda...
bezveznu, apstraktnu razonodu.
Koji je konkretno benefit ljucke vrste od svega toga?

spoznaja, ne igra ulogu oko cega, sve.
realno zivimo na tankoj kori usijane lopte (ili ploce) okruzeni nistavilom i pravimo se kako je bitno bilo sta drugo osim spoznaje.
izjava nije u smislu nekakve hipi-komune, mahanja palminom granom, i slicnih pipla. produktivnost je osigurala elementarne potrebe covjecanstva, prosto je ludilo fokusirati se na bilo sto drugo, staviti je u sluzbu bilo cega (profit, carke izmedju careva i kraljeva i sl.) do znanosti i spoznaje.
i svakih deset godina tri hidrogene bombe na afriku cija ce se populacija u sljedecih deset godina opet udvostruciti.

Quote from: zosko on 12-10-2017, 19:48:01
neutron star collision. :roll:

Colliding neutron stars apply kiss of death to theories of gravity (https://arstechnica.com/science/2017/10/colliding-neutron-stars-decapitate-zombie-theory-of-gravity/)

bas simpaticno napisano. gravitacija je najveci izazov koji moramo ukrotiti da bi dobili novum u sf-a. inace ostaju samo stare price koje se ponavljaju u raznim varijantama. :cry:

Kakav novum? To je još Brik Bradford sredio.

Jedva čekam da svi pokapiraju da je zemlja ravna,
pa da sve astrofizičare lepo i pošteno nazovemo pravim imenima...gatari, zvezdari, vračari, alhemičari, okultisti, obmanjivači...

E, to bi bio SF novum. Izbrisao bi sve do Meri Šeli.

Quote from: scallop on 26-10-2017, 10:00:17
Kakav novum? To je još Brik Bradford sredio.

И Кембел, у Who goes there?, пре скоро 80 година.

Quote from: Ugly MF on 26-10-2017, 10:10:25
Jedva čekam da svi pokapiraju da je zemlja ravna,
pa da sve astrofizičare lepo i pošteno nazovemo pravim imenima...gatari, zvezdari, vračari, alhemičari, okultisti, obmanjivači...

nista nisu postigli dok gravitacione talase ne nauce savinuti u polukrug snagom misli. :roll:

The universe shouldn't exist, scientists say after finding bizarre behaviour of anti-matter (http://www.independent.co.uk/news/science/universe-exist-cern-universe-matter-bizarre-behaviour-scientists-a8015216.html)

Scientists shouldn't exist after last statement about Universe.

Visitor from Far, Far Away: Interstellar Object Spotted in Our Solar System (https://www.space.com/38580-interstellar-object-spotted-comet-asteroid-mystery.html)

Tekst nije naročito sjajan ali ostaviću i link za sam rad...

Dark Matter and Energy Don't Exist: Astronomer Claims to Solve Universe's Greatest Mysteries With New Model (https://www.yahoo.com/news/dark-matter-energy-don-apos-160738754.html)

https://arxiv.org/abs/1701.03964 (https://arxiv.org/abs/1701.03964)

Quote from: Meho Krljic on 26-10-2017, 06:07:50

Quote from: zosko on 12-10-2017, 19:48:01
neutron star collision. :roll:

Colliding neutron stars apply kiss of death to theories of gravity (https://arstechnica.com/science/2017/10/colliding-neutron-stars-decapitate-zombie-theory-of-gravity/)

Two Stars Slammed Into Each Other And Solved Half Of Astronomy's Problems. What Comes Next? (https://fivethirtyeight.com/features/two-stars-slammed-into-each-other-and-solved-half-of-astronomys-problems-what-comes-next/amp/)

Kepler Mission: NASA to Reveal AI Breakthrough Discovery—With a Little Help from Google (http://www.newsweek.com/kepler-nasa-ai-breakthrough-discovery-google-743816)



Naravno, držaće nas u neizvesnosti do Četvrtka...

Nije baš ispalo spektakularno ovo:
NASA Kepler event RECAP: Space agency used Google's artificial intelligence to find new alien planet (http://www.mirror.co.uk/science/nasa-kepler-event-live-latest-11695611)



Mislim, lepo, našli novu planetu, ali nas, blazirane, to više ne impresionira.





Al zato:


Cosmic Filament Probes Our Galaxy's Giant Black Hole (https://www.cfa.harvard.edu/news/2017-35)

Supermassive black holes may control galaxy formation (https://www.engadget.com/2017/12/21/quasars-may-control-galaxy-formation/)


Nažalost, tekst je dosta mutav, ali potrudio sam se da iskopam rad na osnovu kog je napisan, pa, evo ko želi, može:


http://iopscience.iop.org/article/10.1088/1742-6596/372/1/012016 (http://iopscience.iop.org/article/10.1088/1742-6596/372/1/012016)

Detailed image of red giant confirms theory about massive stars (https://www.engadget.com/2018/01/30/detailed-image-of-gruis-red-giant-confirms-theory/)

Mexane, mora te pitam iskreno,
koji je tvoj personalni stav u vezi svih tih svemironskih fantazija.
Verujes u sve to sto ti naucnici napisu ili ne?

Ne veruje. Zna on da je Zemlja ravna.

Meni najbitnije da ti znas!
I Bata!
Za sve ostale, ima vremena, ne moraju svi odma da se opamete....

Bata je ekspert za neoliberalnu ravnu Zemlju. Od 1204. Tada su je poravnali. I utabali.

Neoliberali su za globalizaciju, nači globus iliti loptu. Prevaranti!

Eto. Znao sam da je prevara. Razvučeš globalizaciju oklagijom i eto Ravne Zemlje.

Jebemu, nemoz' Mexo da odgovori od vas, samo mu upadate u rec, e breeeeee....

Ne može on da sabere toliko činjenica koliko gluposti ja mogu da izmislim.

Nema ovde sta da se sabira i oduzima, ili verujes sve ovim astrolozima ili ne verujes nista.
Nema procenata, onda nije nauka, nego teorija...

Znam da je sa naukom zajebano. Taman opeglaš, a ono se zgužva. Teorije su pouzdanije. Odvališ i držiš se toga. Nema Cile-Mile. Pljosnato, od Zaječara do Negotina. Za ostalo, grbavo pa koga se tiče. Da su mi bolje noge ni ja ne bih teturao od sobe do kujne. A ravno, ne možeš da zamisliš.

Kako li su Vojvodjane ubedili u globus?!?

Rekli im da Timočani veruju u Ravnu Zemlju.

Bre, na ovoj Sagiti ne mereš ozbiljno, a ne mereš se ni zajebavati. :x

Sta se lupas uglavu, nije te valjda neko negde naljutio!?!
Evo ja se na leto selim u Zemun, sve cu vi objasnim odatle!

Tek tamo je zakrivljeno! Banjica je Banjica.

Verujem da je ono sa čime se većina naučnika slaže najbliže tom nekom stvarnom stanju stvari.

Fail.
:/
Da ili ne je bio odgovor.

Razumem, ali to samo pokazuje da je pitanje nedovoljno precizno. Nauka ne daje definitivne nego najverovatnije odgovore, ako smem da je tako uprostim. Ako bismo rekli da su pre hiljadu godina "svi", pa i naučnici govorili da je zemlja ravna, to je i dalje bilo bliže nekakvom stanju stvari kako ga ja doživljavam od verovanja da je na leđima nose slonovi a koji stoje na kornjači itd.

Pitanje je precizno da nema vise 'de,
ali meni je svaki tvoj odgovor rekao sve sto treba da znam.

( poenta je bila da ne odgovoris sa DA, onda bi bio beznadezno izgubljen slucaj :D , ali ovako si
normalna osoba s' kojom se moze razgovarati )

Sprocu ove astarotike, jelte, na nju mislim ;)

Ha, naučnici daju odgovore, ha!

Pitam se kolko je Kolumbo uzo keša od kralja!

Kao što Mali Kolumbo sada obećava Vučiću da će grad da bidne na vodi, nauka!

For the First Time, Planets Have Been Discovered in ANOTHER Galaxy! (https://www.universetoday.com/138478/first-time-planets-discovered-another-galaxy/)

 A self-taught astronomer spotted something no scientist had ever seen (https://www.washingtonpost.com/news/speaking-of-science/wp/2018/02/21/a-self-taught-astronomer-spotted-something-no-scientist-had-ever-seen/?utm_term=.87e5ad920ab0)

fala mehane, ovo su događaji zbog kojih se voli nauka. :)

Služimo narodu. Mislim, supernove su jedna od najspektakularnijih zamislivih pojava u univerzumu, what's not to love?  :lol: :lol: :lol:

Opet kokica.

Hubble: Universe Is Expanding Faster Than It Should—and We Need a New Physics to Explain It (http://www.newsweek.com/universe-expansion-hubble-space-telescope-817511)

(Mada je tekst zbunjen i zbrdazdoljen... Ali eto, nek stoji bar osnovna informacija)

Astronomers Capture Clearest Infrared Image To Date of the Center of the Milky Way  (https://scitechdaily.com/astronomers-capture-clearest-infrared-image-to-date-of-the-center-of-our-galaxy/)

Some Black Holes Erase Your Past and Give You Unlimited Futures (https://motherboard.vice.com/en_us/article/xw57nw/black-hole-erase-past-infinite-future-cauchy)



Pošto je ovaj Madrbordov članak dosta.... laiciziran i nedovoljno jasan, evo i linka do originalnog rada:


https://arxiv.org/abs/1711.10502




Naravno, što se mene tiče, mogo je biti napisan i na kineskom...

Quote from: Meho Krljic on 01-03-2018, 08:46:11
Some Black Holes Erase Your Past and Give You Unlimited Futures (https://motherboard.vice.com/en_us/article/xw57nw/black-hole-erase-past-infinite-future-cauchy)



Pošto je ovaj Madrbordov članak dosta.... laiciziran i nedovoljno jasan, evo i linka do originalnog rada:


https://arxiv.org/abs/1711.10502




Naravno, što se mene tiče, mogo je biti napisan i na kineskom...

Гос'н Крљић, ако је за утеху, ја нисам потпуни лаик, ево нпр. сад бих извео формулу за Риман-Кристофелов тензор, али сам тензорски рачун и диференцијалну геометрију учио из неких старих књига и скраћених курсева тако да и мени чланак делује као кинески.

Ostaje da im verujemo da su crne rupe praktično magija  :lol:

Quote from: Meho Krljic on 01-03-2018, 21:22:55
Ostaje da im verujemo da su crne rupe praktično magija  :lol:

Pročitati moju kratku priču MUVANJE SA MUFOM. :shock:

Researchers may have detected signals from the universe's first stars (https://www.engadget.com/2018/02/28/researchers-detect-first-stars-in-universe/)

Galaxy seems to lack dark matter, stumping astronomers (https://arstechnica.com/science/2018/03/galaxy-seems-to-lack-dark-matter-stumping-astronomers/)

Hubble spots Einstein ring surrounding galaxy cluster (https://www.upi.com/Science_News/2018/04/06/Hubble-spots-Einstein-ring-surrounding-galaxy-cluster/8921523045223/)

Quote from: Meho Krljic on 21-01-2016, 13:00:53
To je jer je Pluton ražalovan sa statusa planete

Yes, Pluto is a planet (https://www.sfgate.com/news/article/Yes-Pluto-is-a-planet-12893841.php)

Astronomers Track Bizarre Objects Near Milky Way's Central Black Hole (https://www.forbes.com/sites/brucedorminey/2018/06/06/astronomers-track-bizarre-objects-near-milky-ways-central-black-hole/#737c0001f7f1)

 Asteroid with a 13-mile-high mountain is now visible to the naked eye (https://www.mnn.com/earth-matters/space/blogs/asteroid-13-mile-high-mountain-now-visible)

Da čoveku padne kamen sa srca:

Astronomers find remainder of universe's missing ordinary matter (https://www.upi.com/Science_News/2018/06/21/Astronomers-find-remainder-of-universes-missing-ordinary-matter/6611529585511/)

A, evo i ovo:

Precise gravitation lens test confirms general relativity (https://www.upi.com/Science_News/2018/06/21/Precise-gravitation-lens-test-confirms-general-relativity/4471529605564/)

This mysterious space object is baffling astronomers all over the world (http://www.businessinsider.com/this-mysterious-space-object-dubbed-the-cow-is-baffling-astronomers-2018-7?amp%253Butm_medium=referral) 

Kao i:


A massive object devastated Uranus a long time ago and it never fully recovered (https://bgr.com/2018/07/03/uranus-collision-early-solar-system/)

Evo, kome se čita studija koja tvrdi da je verovatnoća da u univerzumu ima još inteligentnog života zapravo mnogo manja nego što smo do sada mislili:


Dissolving the Fermi Paradox (https://arxiv.org/pdf/1806.02404.pdf)

Quote
Abstract

The Fermi paradox is the conflict between an expectation of a high ex ante probability of intelligent life elsewhere in the universe and the
apparently lifeless universe we in fact observe. The expectation that the universe should be teeming with intelligent life is linked to models like the Drake equation, which suggest that even if the probability of intelligent life developing at a given site is small, the sheer multitude
of possible sites should nonetheless yield a large number of potentially observable civilizations. We show that this conflict arises from the use of Drake-like equations, which implicitly assume certainty regarding highly uncertain parameters. We examine these parameters, incorporating models of chemical and genetic transitions on paths to the origin of life, and show that extant scientific knowledge orresponds to uncertainties that span multiple orders of magnitude. This makes a stark difference. When the model is recat to represent realistic distributions of uncertainty, we find a substantial ex ante probability of there being no other intelligent life in ou observable universe, and thus that there should be little surprise whenwe fail to detect any signs of it. This result dissolves the Fermi paradox,
and in doing so removes any need to invoke speculative mechanisms by which civilizations would inevitably fail to have observable effects upon the universe.

Meni sama kovanica 'astrofizika' uvek bila... nebulozna...
Fizika ko naučna grana nečeg svakodnevnog i opipljivog i ono drugo o čemu se pojma blagog nema nego se samo nagađa...
Ljudska vrsta je stvarno fascinantna...

  These swirls of light could be signs of a previous universe existing before ours (https://www.businessinsider.com/swirls-of-light-could-be-a-previous-universe-2018-8?amp%253Butm_medium=referral)

Physicists think they've spotted the ghosts of black holes from another universe (http://www.foxnews.com/science/2018/08/22/physicists-think-theyve-spotted-ghosts-black-holes-from-another-universe.html)

Ovako je nešto se izjavi nakon doooobrog cuga marije ane...

Quote from: Ugly MF on 23-08-2018, 08:28:26
Ovako je nešto se izjavi nakon doooobrog cuga marije ane...

http://tribun.hr/covjek-zavrsio-u-bolnici-nakon-pada-u-umjetnicku-instalaciju-crne-rupe/

Did Scientists Actually Spot Evidence Of Another Universe? (https://www.forbes.com/sites/jesseshanahan/2018/08/24/did-scientists-actually-spot-evidence-of-another-universe/#314705321425) 

Zna se šta kaže Beteridž kad novinski naslov završite upitnikom...

Aha!


Pluto should be reclassified as a planet, experts say (https://www.sciencedaily.com/releases/2018/09/180907110422.htm)

Ako je Pluton planeta onda je to i mesec, i mnogi drugi sateliti. Šta fali da se svi okrugli objekti zovu planetarna tela? Šta su zapeli baš za pojam planete...

Pitaj vavilonce...oni su ih prvi videli...

Kad napisa Ugly, da dodam bez zadnje namere, nego onako žovijalno. Setim se svojih dvoumljenja oko Velike Plane, kad mi nije bilo jasno zašto je starorimsko ime Magnum Planum polovično usvojeno, ni zašto se ne zove Veliko Ravno uz pun prevod. Pa se vratim na planete i planetarna tela i više mi nije čudna ni ravnozemljaška teza, jer ako su planete - ravni, a planetarna tela - ravna tela, onda je i Zemlja - ravna. 8)

scallop= Uglyjev padawan  :lol:

Quote from: Ugly MF on 09-09-2018, 11:38:49
scallop= Uglyjev padawan  :lol:

Samo da ne padnem van.

Nemož' padneš, ima ledeni zid oko Zemljin krug, bezbedan si, uživaj i piskaraj;)

Quote from: Ugly MF on 09-09-2018, 11:20:37
Pitaj vavilonce...oni su ih prvi videli...

Значи, то са равном земљом и куполом су смислили исти они који диверзификују стрипове?

Ravnu Zemlju nije niko smislio, nego Bog stvorio,a o stripovima...to je već druga priča...
sami pojam 'astrofizika' je sajfaj jeres, jer o fizici i nešto znamo, a o 'astrama' samo nagađamo...
oksimoron kao i PC... by my standards...
Nemora niko se složi samnom, uopšte...

Pre 2300 godina Aristotel je svojim učenicima pokazao pet jednostavnih, svakome dostupnih NEOBORIVIH dokaza da je zemlja okrugla.
Koliko čovek danas u XXI veku treba da bude retardiran da zaista veruje da je zemlja ravna?


(https://2.bp.blogspot.com/-2-by4H9mnY8/WUMIrI0ilMI/AAAAAAAAEV0/pyb_8RFzVQoSNsAdIcgALOwYPu-duY5YQCLcBGAs/s1600/IMG_4034.JPG)

Pre više od 6000 Bog je stvorio Ravnu zemlju. Mnogo više NEOBORIVIH dokaza su ljudi pronašli da čak i Bog ne postoji.
Kolko treba da bude retardiran da i dalje veruje da Bog postoji?

Hm, ne izgleda mi da si rekao ono što si želeo da kažeš

Quote from: mac on 09-09-2018, 18:17:50
Hm, ne izgleda mi da si rekao ono što si želeo da kažeš

Ni meni. U prvoj rečenici ugly čvrsto vjeruje u boga i ravnu zemlju. No, kako to sad uskladiti s drugom i trećom rečenicom? :)

Izvor informacije i naučnih dokaza.
Nekom Bog, nekom Aristotel.
Šta je tu nerazumljivo?

Аристотел је ,,european heritage", паган, а европско наслеђе и паганизам сметају овим јудео и јудеохришћанским пустињацима.
Неразумљиво је да Европљани верују у неког неевропског Бога.
Зато нам племе које верује у свог неевропског Бога и представља Тора као коња и као жену, а Бога Хејмдала "глуми" црнац.
Зато тврдим да је Библија заправо Марвел пре Марвела, јер у Библији имамо прве јудео "суперхероје" јудео-марвеловског типа: оног који је спикао са купиновим грмом, затим оног коме је снага лежала у коси, и оног трећег који је ходао по води.

Pa dobro, odakle će da uzmu priče ako ne odatle, tamo su najupečatljivije...
...da su makar nešto skapirali iz tih priča....

Тора нису узели одатле, зато се и иживљавају над њим, исто као што се равноземљаши иживљавају над Аристотелом.

Kako bre, a Ilija Gromovnik?!?

Њега су мазнули од нас, али су га са божанског деградирали на људско, у циљу да га таквом деградацијом подреде њиховом богу.

Quote from: Boban on 09-09-2018, 16:29:02
Pre 2300 godina Aristotel je svojim učenicima pokazao pet jednostavnih, svakome dostupnih NEOBORIVIH dokaza da je zemlja okrugla.
Koliko čovek danas u XXI veku treba da bude retardiran da zaista veruje da je zemlja ravna?


(https://2.bp.blogspot.com/-2-by4H9mnY8/WUMIrI0ilMI/AAAAAAAAEV0/pyb_8RFzVQoSNsAdIcgALOwYPu-duY5YQCLcBGAs/s1600/IMG_4034.JPG)

šta nije jasno? 8-)

(https://img.cliparto.com/pic/xl/185945/3305365-ancient-earth.jpg)

Nači mož se padne sa ivice?

Ne znam, otiđi, probaj...

Bog nije stvar postojanja nego vere.
Nema potrebe da se dokazuje da Bog ne postoji jer nema niti jednog pokazatelja da on zaista postoji. Sve je u veri i samo u veri.
Kao kada bi neko insistirao da dokažemo da npr. u Palićkom jezeru ne živi dinosaurus i zbog toga što mi to ne uspevamo da dokažemo zaključio da postoji.
Ono što ljudi zapravo brkaju jeste poistovećivanje vere u boga s "verom" u nauku, s tim da naučno istraživanje sveta ima pet nivoa: pretpostavka > hipoteza > teorije > teorema > zakon; pretpostavke i hipoteze su podložne preispitivanju i lako se dokazuje da nisu tačne, pa zagovornici Boga uvek mašu sa pretpostavkama i hipotezama ismevajući nauku... kao, eto "vaša nauka" tvrdi ovo i ono... a nauka ništa ne tvrdi, ona ima pet stepenika posmatranja sveta. Maloumni zagovornici religije (ili plaćenici iste u cilju zgrtanja para)  i ne mogu ništa drugo nego da se vataju za naučne pretpostavke i izruguju se njihovoj lakoj oborivosti. Što se ne uhvate Pitagorine teoreme ili Njutnovih i Keplerovih zakona?

Ако постоји "Божја честица", онда постоји и Бог.  8-)

Quote from: Boban on 09-09-2018, 22:17:37
naučno istraživanje sveta ima pet nivoa: pretpostavka > hipoteza > teorije > teorema > zakon;

Zakon da je Zemlja planeta?

https://youtu.be/lqk3TKuGNBA

Мац, дај неки видео са неким нормалним водитељем, немој овог што прави гримасе да би оставио утисак, и на глави држи данца од кока-коле, да људи мисле да је штребер.  :lol:

...izdržao sam dok je rekao da je evolucija činjenica...sorry, nisam najpametniji, ali nisam ni ovolko debilan da će ovaj sad nešto mi objasni...

Svi bi da budu neoliberali, a da im ne uđe..

Ne razumem.
I ne znam šta je u tebe ušlo, pa si postao tolki neoliberal,
al' Hvala Bogu što ti i ja nemamo mnogo zajedničko u mišljenjima....

Neoliberal je neko ko smatra da je u pravu (povrh drugih detalja koji sad nisu bitni). Ali da bi bio u pravu mora prvo da ti uđe pamet u glavu. Ne možeš samo da veruješ da si u pravu.

U drugom sloju aforizma ima tu i nekog seksa, ali ne znam kako da objasnim. Možda sam u drugom sloju malo i promašio temu.

Ja mislim da na topiku o neoliberalizmu, Bata, Scallop ,Aksentije, a evo čak i ja jeeeedva čekamo da nam baš ti objasniš šta je neoliberalizam!
Evo sad si me zaintrigririsao, baš želim da saznam!

Quote from: Ugly MF on 10-09-2018, 11:56:32
Ja mislim da na topiku o neoliberalizmu, Bata, Scallop ,Aksentije, a evo čak i ja jeeeedva čekamo da nam baš ti objasniš šta je neoliberalizam!
Evo sad si me zaintrigririsao, baš želim da saznam!

:| :| :| :| :| :| xcheers

inače, nije zgoreg spomenuti da je Hajekov ćale biolog, da mu je best friend Bertalanfi biolog, da se fura evolucija kao tržište

ali kao što Sanders reče, it's rigged, tržište i evolucija!

njima se Zemlja okreće zato što se para okreće

Digresija oko zakona neverovatnoće...astroloških nemogućnosti i astralnih zavera,
juče ovde s' Bobanom razmenim 2 posta i ubeđen sam da je danas prošetao pored mene u Comtrade ITHS!
Nikad ga lično nisam vidjo, samo ovde na fotkama, a i nešto sam bio pospan....
...ili je bio Boban, ili ima dvojnika!

Ima ih nekoliko. Nikada dva puta isti.

Our universe has antimatter partner on the other side of the Big Bang, say physicists (https://physicsworld.com/a/our-universe-has-antimatter-partner-on-the-other-side-of-the-big-bang-say-physicists/)

Citizen astronomers discover new planet that NASA algorithms missed (https://www.engadget.com/2019/01/09/citizens-discover-new-planet-nasa-algorithms-missed/?yptr=yahoo)

Scientists are just now seeing 13-billion-year-old light from black holes (https://www.usatoday.com/story/news/2019/01/23/black-holes-discovered-early-universe-13-billion-years-ago/2659492002/)

Naučnici izračunali masu Mlečnog puta....

 Scientists solve weighty matter of Milky Way mass  (https://www.msn.com/en-us/news/technology/scientists-solve-weighty-matter-of-milky-way-mass/ar-BBUvClD)

Quote
a team of experts calculated our galaxy to be around 1.5 trillion solar masses.

Eto!

Melodysheep (koga se jelte sećamo po videu A Glorious Dawn (https://youtu.be/zSgiXGELjbc)) ponovo na sasvim zadovoljavajuć način kombinuje zvuk i sliku da opiše buduću istoriju celog svemira:

TIMELAPSE OF THE FUTURE: A Journey to the End of Time (https://youtu.be/uD4izuDMUQA)

hvala:)

Danas (10.4.2019.) nas čeka važna objava. Prva u istoriji fotografija crne rupe. Veritasium kanal u to ime objašnjava kako bi takva slika mogla da izgleda, i zašto.

How to Understand the Image of a Black Hole (https://youtu.be/zUyH3XhpLTo)

Quote from: Meho Krljic on 08-03-2019, 06:17:52
Naučnici izračunali masu Mlečnog puta....

 Scientists solve weighty matter of Milky Way mass  (https://www.msn.com/en-us/news/technology/scientists-solve-weighty-matter-of-milky-way-mass/ar-BBUvClD)

Quote
a team of experts calculated our galaxy to be around 1.5 trillion solar masses.

Eto!

Danima pokušavam da smislim odgovor na bitnost ove informacije i ne mogu....

Quote from: Ugly MF on 03-09-2016, 21:22:19
Pošto ništa u vezi crnih rupa nije dokazano, nego samo teorije postoje, kako ja da verujem u njihovo postojanje?

Quote from: mac on 03-09-2016, 22:32:18
U redu je, imaš mogućnosti da ne veruješ do kraja sledeće godine (https://en.wikipedia.org/wiki/Event_Horizon_Telescope), a onda ćemo dobiti slike i pravi dokaz.

Evo konačno slike masivne crne rupe iz galaksije M87.

https://www.bbc.com/news/science-environment-47873592

to gore od slika "okrugle zemlje", "hoda po mjesecu", "crvene planete", sve vise para, sve manje muzike... uslikaju neku mrlju, puste kroz filter, sve pet do dvanaest i kao nesto radili tristo godina!

U pitanju je objekat veličine celog našeg solarnog sistema. Jedna crna rupa velika kao orbita Neptuna. Ne bih ja to okarakterisao kao "sve manje muzike". Od ove muzike atomi se raspadaju na kvarkove i druge egzotične čestice.

da, da... samo, sta je tu veliko "kao orbita neptuna", a sta je tu krofna? nekad su se bas trudili, danas uslikaju bilo sta...

(https://s16.directupload.net/images/190410/oxveti73.jpg)

Ne mogu da smislim i dalje šta da komentarišem na sve ovo... Ne ide mi...

Quote from: Ugly MF on 10-04-2019, 21:07:55
Ne mogu da smislim i dalje šta da komentarišem na sve ovo..

Ništa, žvakni krofnicu i nastavi šutjeti.. 🙂

agli ima moju podršku!  xrofl

New Hubble measurements confirm universe is expanding faster than expected (https://www.sciencedaily.com/releases/2019/04/190425104128.htm)

Quote
New measurements from NASA's Hubble Space Telescope confirm that the Universe is expanding about 9% faster than expected based on its trajectory seen shortly after the big bang, astronomers say. 

Researchers decipher the history of supermassive black holes in the early universe (https://phys.org/news/2019-06-decipher-history-supermassive-black-holes.html)


Konkretnije, ovaj rad pokazuje  (https://iopscience.iop.org/article/10.3847/2041-8213/ab2646)mehanizam po kome supermasivne crne rupe(možda) nisu nastale od zvezda jer su se formirale tako brzo da su "odmah" kolabirale u, jelte singularitet.

Scientists Are Arguing About Dark Matter Again (https://www.popularmechanics.com/space/deep-space/a28409626/dark-matter-debate/)

Star orbiting massive black hole lends support to Einstein's theory (https://www.reuters.com/article/us-space-gravity/star-orbiting-massive-black-hole-lends-support-to-einsteins-theory-idUSKCN1UK2U3)

Astronomers find traces of one of the first stars (https://www.anu.edu.au/news/all-news/astronomers-find-traces-of-one-of-the-first-stars)

  Kepler's forgotten ideas about symmetry help explain spiral galaxies without the need for dark matter – new research  (http://theconversation.com/keplers-forgotten-ideas-about-symmetry-help-explain-spiral-galaxies-without-the-need-for-dark-matter-new-research-121017)

Pokušavam da dozovem Aglija ovakvim vestima:


Dark matter may be older than the Big Bang (https://www.sciencedaily.com/releases/2019/08/190807190816.htm)

Quote"The study revealed a new connection between particle physics and astronomy. If dark matter consists of new particles that were born before the Big Bang, they affect the way galaxies are distributed in the sky in a unique way. This connection may be used to reveal their identity and make conclusions about the times before the Big Bang too," says Tommi Tenkanen, a postdoctoral fellow in Physics and Astronomy at the Johns Hopkins University and the study's author.

Brzina ekspanzije svemira nikako da poprimi neku logičnu vrednost.


One Number Shows Something Is Fundamentally Wrong with Our Conception of the Universe (https://www.space.com/hubble-constant-discrepancy-explained.html)

Astronomers Detect the Most Massive Neutron Star Yet (https://www.space.com/most-massive-neutron-star-detected.html)

QuoteThe newly measured neutron star, called J0740+6620, lies about 4,600 light-years from Earth. It packs 2.14 times the mass of the sun (https://www.space.com/42649-solar-mass.html) into a sphere only about 15 miles (25 km) in diameter. That approaches the theoretical limits of how massive and compact a single object can become without crushing itself down under the force of its own gravitational pull into a black hole.

The Milky Way Has Giant Bubbles at Its Center (https://www.theatlantic.com/science/archive/2019/09/milky-way-galaxy-bubbles-meerkat/598552/?utm_medium=offsite&utm_source=yahoo&utm_campaign=yahoo-non-hosted&yptr=yahoo)

Ovo je sve za sada prilična spekulacija, rad na kome se članak zasniva nije još ni publikovan, ali je zanimljivo:

If Planet 9 Is Actually a Black Hole, It Completely Changes How We Understand Our Universe (https://www.popularmechanics.com/space/solar-system/a29306276/black-hole-solar-system/)

    Scientists start mapping the hidden web that scaffolds the universe  (http://theconversation.com/scientists-start-mapping-the-hidden-web-that-scaffolds-the-universe-124616)

QuoteAfter counting all the normal, luminous matter in the obvious places of the universe – galaxies, clusters of galaxies and the intergalactic medium – about half of it is still missing. So not only is 85% of the matter in the universe made up of an unknown, invisible substance dubbed "dark matter" (https://theconversation.com/why-do-astronomers-believe-in-dark-matter-122864), we can't even find all the small amount of normal matter that should be there.
This is known as the "missing baryons" problem (https://en.wikipedia.org/wiki/Missing_baryon_problem). Baryons are particles that emit or absorb light, like protons, neutrons or electrons, which make up the matter we see around us. The baryons unaccounted for are thought to be hidden in filamentary structures permeating the entire universe, also known as "the cosmic web".

         

Evo studije na kojoj je članak baziran  ako neko želi da se napoji direkt sa izvora (i ako plaća pretplatu..):

Gas filaments of the cosmic web located around active galaxies in a protocluster (https://science.sciencemag.org/content/366/6461/97)   

Quote from: Meho Krljic on 04-10-2019, 05:52:01[/b]Evo studije na kojoj je članak baziran  ako neko želi da se napoji direkt sa izvora (i ako plaća pretplatu..):

Gas filaments of the cosmic web located around active galaxies in a protocluster (https://science.sciencemag.org/content/366/6461/97)   

ArXiv je majka svih arhiva ;)

https://arxiv.org/abs/1910.01324

Quote from: Meho Krljic on 18-08-2018, 06:43:25
Evo, kome se čita studija koja tvrdi da je verovatnoća da u univerzumu ima još inteligentnog života zapravo mnogo manja nego što smo do sada mislili:


Dissolving the Fermi Paradox (https://arxiv.org/pdf/1806.02404.pdf)

Quote
Abstract

The Fermi paradox is the conflict between an expectation of a high ex ante probability of intelligent life elsewhere in the universe and the
apparently lifeless universe we in fact observe. The expectation that the universe should be teeming with intelligent life is linked to models like the Drake equation, which suggest that even if the probability of intelligent life developing at a given site is small, the sheer multitude
of possible sites should nonetheless yield a large number of potentially observable civilizations. We show that this conflict arises from the use of Drake-like equations, which implicitly assume certainty regarding highly uncertain parameters. We examine these parameters, incorporating models of chemical and genetic transitions on paths to the origin of life, and show that extant scientific knowledge orresponds to uncertainties that span multiple orders of magnitude. This makes a stark difference. When the model is recat to represent realistic distributions of uncertainty, we find a substantial ex ante probability of there being no other intelligent life in ou observable universe, and thus that there should be little surprise whenwe fail to detect any signs of it. This result dissolves the Fermi paradox,
and in doing so removes any need to invoke speculative mechanisms by which civilizations would inevitably fail to have observable effects upon the universe.

Slično:

    Evolution tells us we might be the only intelligent life in the universe  (http://theconversation.com/evolution-tells-us-we-might-be-the-only-intelligent-life-in-the-universe-124706)   

    Dark energy: new experiment may solve one of the universe's greatest mysteries  (http://theconversation.com/dark-energy-new-experiment-may-solve-one-of-the-universes-greatest-mysteries-125886) 

  How we discovered a glowing galactic ghoul  (http://theconversation.com/how-we-discovered-a-glowing-galactic-ghoul-121827)

Physicists simulate critical 'reheating' period that kickstarted the Big Bang (https://phys.org/news/2019-10-physicists-simulate-critical-reheating-period.html)

 Scientists may just have discovered a new class of black holes (https://news.osu.edu/scientists-may-just-have-discovered-a-new-class-of-black-holes/)

 NASA's Voyager 2 spacecraft beamed back unprecedented data from interstellar space. It indicates a mysterious extra layer outside our solar system. (https://www.businessinsider.com/nasa-voyager-interstellar-space-findings-outside-solar-system-2019-11)

Voyager 1 je dosta brži od sonde blizanca Voyager 2 stoga je i ranije prošao kroz heliopauzu i tako ušao u međuzvezdani prostor.

https://voyager.jpl.nasa.gov/mission/status/ (https://voyager.jpl.nasa.gov/mission/status/)

https://www.skyandtelescope.com/astronomy-news/interstellar-space-the-view-voyager-2/ (https://www.skyandtelescope.com/astronomy-news/interstellar-space-the-view-voyager-2/)

Treba imati na umu da sonde Voyager ne idu jedna za drugom, zapravo sada se kreću jedna južno a drugo severno od ravni ekliptike odnosno ravni revolucije Zemlje oko Sunca.
Moguće je uzimajući u obzir nagib ekliptike u odnosu na ravan Galaksije i u odnosu na pravac kretanja Sunca oko centra same Galaksije do to ima uticaja na očitavanja instrumenata na sondama.
Drugim rečima heliosfera najverovatnije ni nema sferičan oblik već drugačije oblikovan samim kretanjem Sunca.

(https://upload.wikimedia.org/wikipedia/commons/thumb/b/b8/Motion_of_Sun%2C_Earth_and_Moon_around_the_Milky_Way.jpg/800px-Motion_of_Sun%2C_Earth_and_Moon_around_the_Milky_Way.jpg)

What Shape Is the Universe? A New Study Suggests We've Got It All Wrong (https://www.quantamagazine.org/what-shape-is-the-universe-closed-or-flat-20191104)

Evo i cele studije:


https://arxiv.org/pdf/1911.02087.pdf (https://arxiv.org/pdf/1911.02087.pdf)

Poštovani Meho nije li poželjno ponekad napisati i poneki komentar sem postavljanja linkova na po pravilu strane sajtove?
Svaka vama čast što vas toliko toga očito interesuje ali ovo bi zaista trebalo da ispoštujete.

Merkurov tranzit(prolazak) ispred Sunca

http://rs.n1info.com/SciTech/a542887/Redak-fenomen-u-Srbiji-Danas-cemo-moci-da-vidimo-Merkur.html (http://rs.n1info.com/SciTech/a542887/Redak-fenomen-u-Srbiji-Danas-cemo-moci-da-vidimo-Merkur.html)

Šta se zapravo događa "tamo daleko"...

https://www.zvjezdarnica.com/astronomija/dogadaji-ove-godine/promatrajte-merkurov-tranzit-ispred-sunca/2927 (https://www.zvjezdarnica.com/astronomija/dogadaji-ove-godine/promatrajte-merkurov-tranzit-ispred-sunca/2927)

kad sam ja bio mlad, verovalo se da je Sunčev sistem prečnika 300 milijardi kilometara, a sada vidim da se pominje 10x manja vrednost. Realno, Sunčev sistem je doklegod gravitacija Sunca nešto drži i privlači, a ne samo doseg magnetnog polja.

Inače ovom metodom tranzita ili okultacije se otkrivaju vansolarne planete oko drugih zvezda.
Golom oku nevidljivo ali osetljivim instrumentima merljivo smanjenje sjaja zvezde izazvano praktično "pomračenjem" daleke planete oko matične zvezde je dokaz da ista postoji.

There's Growing Evidence That the Universe Is Connected by Giant Structures (https://futurism.com/the-byte/something-strange-synchronizing-distant-galaxies)

QuoteScientists are finding that galaxies can move with each other across huge distances, and against the predictions of basic cosmological models. The reason why could change everything we think we know about the universe.

New type of star system? Mysterious radio signal puzzles astronomers  (http://theconversation.com/new-type-of-star-system-mysterious-radio-signal-puzzles-astronomers-127699) 


A ima i ovo:


A Missing Neutron Star May Have Been Found after 30-Year Hunt (https://www.scientificamerican.com/article/a-missing-neutron-star-may-have-been-found-after-30-year-hunt/)

Huge Black Hole 'That Shouldn't Exist in Our Galaxy' Discovered by Scientists (https://www.newsweek.com/black-hole-shouldnt-exist-milky-way-1474428)

An experiment that solved a 100-year-old mystery posed by Einstein just got up to 50% more powerful by squeezing light (https://www.businessinsider.com/ligo-gravitational-wave-detector-more-powerful-squeezing-light-2019-12)

Quote
One of the most remarkable experiments in history — a trio of giant machines that listen for ripples in spacetime called gravitational waves (https://www.businessinsider.com/objects-gravitational-waves-can-detect-2016-2/?r=AU&IR=T) — just got more powerful and precise.

Will We Ever Find Dark Matter in the Universe? (https://time.com/5744094/find-dark-matter-universe/) 

Quote
One newly popular idea is that the dark matter might not be alone, but instead could be one of several kinds of particles that constitute what is known as a "hidden sector." The particles that make up such a hidden sector could interact among each other, but almost never with any of the known forms of matter, explaining why they have been so difficult to detect in underground experiments or to produce at the Large Hadron Collider. The particles that make up a hidden sector could have evolved and interacted in the early universe in any number of potentially complex ways, even experiencing forces that we have never witnessed. Particle physicists have proposed many theories in which the interactions between multiple kinds of hidden matter can lead to the viable production of dark matter in the early universe. In fact, it's been quite easy for particle physicists to come up with viable hidden sector theories that behave in this way.

This huge galaxy has the biggest black hole ever measured (http://www.astronomy.com/news/2019/12/this-huge-galaxy-has-the-biggest-black-hole-ever-measured)

QuoteThe monster black hole in galaxy cluster Abell 85 is roughly the size of our solar system, but packs the mass of 40 billion suns.

:shock: :shock: :shock: :shock:
Da prevedemo: to je masa približno ekvivalentna dvema trećinama čitavog Mlečnog puta. MASIVNO.

Koja je max veličina zvezde koju dozvoljavaju zakoni fizike?

http://www.astronomy.com/magazine/ask-astro/2018/06/big-stars?utm_source=Yesmail&utm_medium=email&utm_campaign=News0_ASY_191213_000000

Astronomers find 19 more galaxies missing their dark matter (http://www.astronomy.com/news/2019/12/astronomers-find-19-more-galaxies-missing-their-dark-matter) 

Tamna materija je stvarno glavobolna, ne valja kad je ima, ne valja kad je nema...

Mysterious ancient event 'set off 100,000 supernova explosions in our galaxy' (http://stocknewspress.com/2019/12/18/mysterious-ancient-event-set-off-100-000-supernova.html)

Astronomers discover class of strange objects near our galaxy's enormous black hole (https://phys.org/news/2020-01-astronomers-class-strange-galaxy-enormous.html)

What if the Shape of the Universe Is Curved? (https://nationalinterest.org/blog/buzz/what-if-shape-universe-curved-118271) 

Quote

Now our new paper, published in Nature Astronomy (https://www.nature.com/articles/s41550-019-0906-9?utm_campaign=MultipleJournals_USG_ASTRO&utm_source=Nature_community&utm_medium=Community_sites&utm_content=BenJoh-Nature-MultipleJournals-Astronomy_and_Astrophysics-Global), has come to a conclusion that may unleash a crisis in cosmology – if confirmed. We show that the shape of the universe may actually be curved rather than flat, as previously thought – with a probability larger than 99%. In a curved universe, no matter which direction you travel in, you will end up at the starting point – just like on a sphere. Though the universe has four dimensions, including time.

    The result was based on recent measurements of the Cosmic Microwave Background (https://theconversation.com/the-cmb-how-an-accidental-discovery-became-the-key-to-understanding-the-universe-45126), the light left over from the Big Bang, collected by the Planck Satellite (https://sci.esa.int/web/planck). According to Albert Einstein's theory of general relativity (https://theconversation.com/how-einsteins-general-theory-of-relativity-killed-off-common-sense-physics-50042), mass warps space and time around it. As a result, light rays take an apparent turn around a massive object rather than travelling in a straight line – an effect known as gravitational lensing (https://theconversation.com/how-we-managed-what-einstein-thought-was-impossible-and-used-his-theory-to-weigh-a-star-79050).

This Is Wild: Astrophysicists Can See Stars Twisting Space and Time (https://www.popularmechanics.com/science/a30729697/evidence-frame-dragging-space-time/) 

Quote
The system, named PSR J1141-6545, is made of two stars: "One is a white dwarf, the size of the Earth but 300,000 times its density; the other is a neutron star which, while only 20 kilometres in diameter, is about 100 billion times the density of the Earth," the press release says.

(...)

All of this means that for the first time, astrophysicists have recorded evidence of the predicted phenomenon of frame dragging. If spacetime is colloquially indeed a "fabric," it's an elastic one, where spinning objects receive that stored energy back from the fabric of spacetime itself. And objects within spacetime can pass energy back and forth the same way, making it both convenient and attractive, literally, to join into energy-saving pairs like this binary system.

   Scientists puzzled by ancient monster galaxy which was suddenly 'snuffed out' (https://www.yahoo.com/news/monster-galaxy-went-dark-181230220.html) 

"Snuffed out" u smislu da više ne proizvodi nove zvezde, i mada tekst treba čitati uz dosta rezervi, zanimljiv je.

Two Black Holes Are Merging at the Center of a Distant Galaxy (https://www.popularmechanics.com/space/deep-space/a30914865/spikey-black-holes/) 

"Merging" je možda prejaka reč za dva objekta u dve različite galaksije, a koja kruže oko zajeedničkog središta ali ima tu flertovanja.

 The growing crisis in cosmology (https://theweek.com/articles/889916/growing-crisis-cosmology)

Dalja priča o Hablovoj konstanti.

"Cosmic String" Gravitational Waves Could Solve Antimatter Mystery (https://www.scientificamerican.com/article/cosmic-string-gravitational-waves-could-solve-antimatter-mystery/)

 Physicists Think We Might Have a New, Exciting Dark Matter Candidate  (https://www.sciencealert.com/d-star-hexaquark-particles-could-be-responsible-for-creating-dark-matter)

Nije baš "astrofizika", više fizika osnovnih čestica, ali sve je to povezano.

 Strange pulses lead astronomers to first 'teardrop' star ever found (https://www.theweathernetwork.com/ca/news/article/bizarre-teardrop-pulsating-star-found-by-astronomers)

NASA Experiment Weakens String Theory, but Doesn't Disprove It (https://www.popularmechanics.com/science/a31898338/nasa-experiment-string-theory/)

 Hubble captures the immense 'tsunami' power of quasars  (https://www.engadget.com/2020-03-25-hubble-quasar-tsunami-illustration.html)

Physicists brawl over new dark matter claim (https://www.sciencemag.org/news/2020/03/physicists-brawl-over-new-dark-matter-claim#) 

"Sterilni neutrino" zvuči kao neka ekstremno kastrirana verzija nosoroga.

Melodysheep, audio-vizuelni umetnik, koji nam je pre desetak godina podario A Glorious Dawn (https://youtu.be/zSgiXGELjbc), a pre godinu dana TIMELAPSE OF THE FUTURE: A Journey to the End of Time (https://youtu.be/uD4izuDMUQA), juče je objavio novi kosmogonijski uradak, The Secret History of the Moon (https://youtu.be/6SrsZVdU740).

Vrlo je zanimljivo da sam danas pomislio na Glorious Dawn video, i poželeo da ga ponovo vidim i čujem, i tako otkrio novi video star tek jedan dan. Nije bilo nikakvog podsticaja od strane Jutjuba, ili bilo koga drugog. Zanimljiva koincidencija.

Konstanta fine strukture (https://en.wikipedia.org/wiki/Fine-structure_constant), konstanta koja povezuje naboj elektrona, Plankovu konstantu, i brzinu svetlosti, možda ipak nije konstanta.

https://www.sciencedaily.com/releases/2020/04/200427102544.htm

Ispostavlja se da naš svemir ima nekakav gradijent, ili "polove". U jednom pravcu ova "konstanta" se povećava, a u suprotnom se smanjuje. Vrlo neobično.

S konstantama je uvek kilavo. Često, zamalo pa nisu.

Ne znam šta to znači. Elem, ova konstanta nema dimenziju, nego samo vrednost, približno 1/137. Već samim tim je vrlo posebna među drugim konstantama. To što je tamo negde u pravcu sazvežđa Oltar, 10 milijardi svetlosnih godina daleko, ova konstanta malo drugačija od naše znači da je tamo negde ili Plankova konstanta drugačija, ili je brzina svetlosti drugačija, ili je naboj elektrona drugačiji. Ili, ko zna, svo troje istovremeno. Vrlo fascinantno.

Pa, upravo to znači. Konstantne su privremene. Dok traju. Kad bi neko čitao ovo šta pišem, možda bih mogao da objasnim da su sve konstante proizvod promenljivih veličina koje se uklapaju u nešto šta nazivamo c, k ili nekako drugačije. Nauka koja to ne priznaje nije nauka nego dogma. Sa dogmama nikad nismo imali previše sreće.

Tako blizu a tako daleko(za sada barem).

https://www.astronomija.org.rs/galaksije/crne-rupe/14020-najbliza-crna-rupa

Ako se ne varam oko lokacije bila bi "vrhunska ironija" da je prva najbliža crna rupa otkrivena u sazvežđu Lyra, u kojem se odigrava Lemov Fijasko.

Naučnici snimili rađanje zvezdanog sistema

https://www.b92.net/zivot/nauka.php?yyyy=2020&mm=05&dd=20&nav_id=1686023

  Half the matter in the universe was missing – we found it hiding in the cosmos  (https://theconversation.com/half-the-matter-in-the-universe-was-missing-we-found-it-hiding-in-the-cosmos-138569) 

Naslov je malko tabloidan ali tekst je napisan jasno i kvalitetno a autori su profesori astrofizike.

  Could we extract energy from a black hole? Our experiment verifies old theory  (https://theconversation.com/could-we-extract-energy-from-a-black-hole-our-experiment-verifies-old-theory-141464)

Možemo ako energiju sačekamo sa druge strane rupe.

Eh, pa cela ova teorija je o tome kako da je dohvatimo sa "ove" strane. Sve je to još vrlo daleko od bilo kakve jasne praktičnosti ali je zanimljivo.

Kao griz za doručak. Možeš da pokupiš sa ivica, ali nikako iz sredine. Vruće je. U svakom slučaju, dobar SF izazov. Čitao sam neke dobre stare romane i može opet. Sa krljanjima, zaverama, zapletima i preokretima.

Ipak, ja bih priču sa druge strane rupe. Treba samo da je nađemo. Negde oko Velikog Praska. Ili, praskova?

Astronomers Spot Strange Space Object, Have No Idea What It Is (https://www.popularmechanics.com/space/deep-space/a33275937/odd-radio-circles/) 

Simpatično je što su ove stvari nazvali "odd radio circles".  :lol:

Is Planet 9 Actually A Primordial Black Hole? (https://www.forbes.com/sites/brucedorminey/2020/07/11/is-planet-9-actually-a-primordial-black-hole/#5dab78014d80) 

Znamo već šta kaže Beteridžov zakon naslova: ne. Ali zanimljiva spekulacija.

  Dark energy: map gives clue about what it is – but deepens dispute about the cosmic expansion rate  (https://theconversation.com/dark-energy-map-gives-clue-about-what-it-is-but-deepens-dispute-about-the-cosmic-expansion-rate-143200?yptr=yahoo)

A vi mislili da je 2020. godina teška zbog pandemije i izbornih uzbuđenja:

There is something strange about our universe, scientists find after mapping the cosmos (https://www.independent.co.uk/life-style/gadgets-and-tech/news/universe-map-dark-matter-homogenous-kids-standard-model-einstein-a9647186.html)

Mislim, naravno, naslov je smešan, ali ovo je šta se dešava:

QuoteThe universe is almost 10 per cent more homogenous than our current understanding of physics suggests.

Tekst sugeriše da će izvesne značajne teorije sa kojima danas baratamo morati da se menjaju ili dopune...

Plesačima na kraju vremena barem neće biti dosadno:

This is the way the universe ends: not with a whimper, but a bang (https://www.sciencemag.org/news/2020/08/way-universe-ends-not-whimper-bang)

Astronomers find "Milky Way look-alike" baby galaxy 12 billion light years from Earth (https://www.cbsnews.com/news/astronomers-find-milky-way-look-alike-galaxy-12-billion-light-years-from-earth/) 

Siguran sam da je samo koincidencija što ta galaksija izgleda tačno kao tamni žig iz Dark Souls igara...


(https://i.imgur.com/mZapkk1.jpg)

  Gravitational waves: astronomers spot a black hole so massive they weren't sure it could exist  (https://theconversation.com/gravitational-waves-astronomers-spot-a-black-hole-so-massive-they-werent-sure-it-could-exist-145474) 

Podsećanje da su teorije najbolje što imamo dok ih praksa ne demantuje.

Pa ne, imamo teoriju i za to. Lepo piše, crne rupe sa nemogućim masama ne nastaju od zvezda nego spajanjem lakših crnih rupa.

Yes, yes, to je novija teorija, evolucija razmišljanja.

Physicists Argue That Black Holes From the Big Bang Could Be the Dark Matter (https://www.quantamagazine.org/black-holes-from-the-big-bang-could-be-the-dark-matter-20200923/)

We have seen hints of a new fundamental force of nature (https://www.newscientist.com/article/mg24632821-000-we-have-seen-hints-of-a-new-fundamental-force-of-nature/?utm_medium=social&utm_campaign=echobox&utm_source=Twitter#Echobox=1601481762)

 An earlier universe existed before the Big Bang, and can still be observed today, says Nobel winner  (https://www.telegraph.co.uk/news/2020/10/06/earlier-universe-existed-big-bang-can-observed-today/)

traže mi da se registrujem da bih mogao da pročitam, neoliberali!

A, da, evo ima i na Jahuu, a gde sa ja to originalno i video.

https://news.yahoo.com/earlier-universe-existed-big-bang-174323840.html

Astronomers captured rare images of a black hole shredding a star into spaghetti-like strands and devouring it (https://www.businessinsider.com/astronomers-capture-a-black-hole-shredding-star-into-spaghetti-strands-2020-10)

Quote from: Meho Krljic on 13-10-2020, 06:07:40
Astronomers captured rare images of a black hole shredding a star into spaghetti-like strands and devouring it (https://www.businessinsider.com/astronomers-capture-a-black-hole-shredding-star-into-spaghetti-strands-2020-10)

"World Prize" а треба Wolf Prize.

Scientists Recreated the Nuclear Reaction That Happened Right After the Big Bang (https://www.popularmechanics.com/space/a34660789/scientists-recreate-nuclear-reaction-after-big-bang/)

To explain away dark matter, gravity would have to be really weird, cosmologists say (https://www.sciencemag.org/news/2020/11/explain-away-dark-matter-gravity-would-have-be-really-weird-cosmologists-say)

Experimental evidence of neutrinos produced in the CNO fusion cycle in the Sun (https://www.nature.com/articles/s41586-020-2934-0)

Ništa ja ovo ne razumem ali evo:

The Sun Is Experiencing a Second Fusion (https://www.popularmechanics.com/science/energy/a34826097/sun-second-fusion-neutrinos/)

Physicists Nail Down the 'Magic Number' That Shapes the Universe (https://www.quantamagazine.org/physicists-measure-the-magic-fine-structure-constant-20201202/)

Ovako bez gledanja, jel 42 i tri u federaciji?

Hahah, i ja sam se to pitao ali ne, odgovor je actually zanimljiviji.

Teorija struna i crne rupe - dve stvari koe zajedno idu kao čokolada i smoki:

Black Holes May Not Be Black Holes at All. They May Actually Be Fuzzballs. (https://www.popularmechanics.com/science/a34873839/black-holes-fuzzballs-string-theory/)

https://www.youtube.com/watch?v=4Q-M7jbq38Q

    Fragments of energy – not waves or particles – may be the fundamental building blocks of the universe  (https://theconversation.com/fragments-of-energy-not-waves-or-particles-may-be-the-fundamental-building-blocks-of-the-universe-150730) 


Autor je profesor mašinstva, doduše za kosmička plovila, kao i njegov koautor, pa ovo možda treba i gledati malo skeptičnije. Naravno, pitanje je koliko bih ja i razumeo njihovu matematiku, ali žurnal u kome su objavili rad mi prvo traži 140 dolara tako da... 

Ne treba se pitati kako je počelo, jer je sledeće pitanje šta je bilo pre toga.

Maybe 'dark matter' doesn't exist after all, new research suggests (https://www.nbcnews.com/science/space/maybe-dark-matter-doesn-t-exist-after-all-new-research-n1252995)

Most Distant Quasar Discovered Sheds Light on How Black Holes Grow (https://news.arizona.edu/story/most-distant-quasar-discovered-sheds-light-how-black-holes-grow) 

Ludilo. Teza je da supermasivna crna rupa u centru nije nastala od zvezda - ili ne prevashodno od zvezda - većm velikim delom od "hladnog" vodonika kog je bilo u izobilju ovako rano u životu univerzuma.


A u donekle povezanim novostima:


Astronomers spotted a galaxy dying after a major collision. It's bleeding out 10,000 suns' worth of gas each year. (https://www.businessinsider.com/astronomers-discover-dying-galaxy-bleeding-gas-into-space-2021-1)

An ancient super-Earth offers an unexpected clue that life in our galaxy could be older than scientists thought (https://www.businessinsider.com/ancient-super-earth-suggests-longer-timeline-for-alien-life-2021-1)

Astronomers may have detected background ripples in spacetime itself  (https://newatlas.com/physics/background-gravitational-wave-signal/)

Missing Matter Found in Our Own Galaxy (https://nerdist.com/article/missing-matter-milky-way-galaxy/)

Black Holes May Not Be Black. Or Even Holes. (https://www.popularmechanics.com/space/deep-space/a35875454/what-are-black-holes-new-theory/)

Naslov nije sjajan (možda 4/10) ali hipoteza u tekstu je zanimljiva.

New dark matter map reveals cosmic mystery (https://www.bbc.com/news/science-environment-57244708)


A ima i ovo:


Study reveals new details on what happened in the first microsecond of Big Bang (https://phys.org/news/2021-05-reveals-microsecond-big.html)

Trebalo bi organizirati "Einstein was wrong drinking game". Kad god se u nekom tekstu pojave ove tri riječi, trgneš jednu. Vjerojatno bi živio još godinu dana, ali kakva bi to godina bila!

A New Space Discovery May 'Overturn Cosmology As We Know It' (https://nerdist.com/article/giant-arc-of-galaxies-overturn-cosmology/)

Stephen Hawking's Theory on Black Hole Surface Area Was Right (https://nerdist.com/article/study-supports-stephen-hawking-black-hole-surface-area-theory/)

The Center of the Milky Way Might Not Be a Black Hole After All (https://www.popularmechanics.com/space/deep-space/a36530817/the-center-of-the-milky-way-might-not-be-a-black-hole-after-all/)

Astronomers work out when the first stars shone (https://www.bbc.com/news/science-environment-57515422)

Elusive new type of supernova, long sought by scientists, actually exists (https://www.space.com/new-supernova-type-discovery)

'Warping space': For the first time, light has been spotted from behind a black hole (https://www.usatoday.com/story/news/nation/2021/07/28/black-hole-light-spotted-behind-one-first-time/5406328001/)

Kako su krenuli na kraju će ima najlakše biti da dokažu da je sve napravio Bog...

New type of dark energy could solve Universe expansion mystery (https://www.nature.com/articles/d41586-021-02531-5)

A Triple-Star System Is Either Hiding a Planet, or Defying the Laws of Physics (https://www.thedailybeast.com/triple-star-system-gw-orionis-is-either-hiding-a-planet-or-a-physics-breaking-secret)

Peering at the edge of the universe (https://theweek.com/science/1006502/peering-at-the-edge-of-the-universe)

Quote
NASA is preparing to launch the most powerful space telescope ever. What will it see?

The problem with the Big Bang theory (https://edition.cnn.com/2021/11/04/opinions/problem-with-the-big-bang-theory-lincoln/index.html)

This Massive Planet Shouldn't Exist (https://gizmodo.com/planet-way-way-bigger-than-jupiter-spotted-in-massive-1848179449)

We may finally be able to test one of Stephen Hawking's most far-out ideas (https://www.livescience.com/testable-primordial-black-holes-theory)

Quote

In the 1970s, Hawking proposed that dark matter (https://www.livescience.com/dark-matter.html), the invisible substance that makes up most matter in the cosmos, may be made of black holes (https://www.livescience.com/black-holes.html) formed in the earliest moments of the Big Bang (https://www.livescience.com/65700-big-bang-theory.html). Now, three astronomers have developed a theory that explains not only the existence of dark matter, but also the appearance of the largest black holes in the universe.

The Hubble telescope just spotted a black hole giving birth to new stars (https://bgr.com/science/the-hubble-telescope-just-spotted-a-black-hole-giving-birth-to-new-stars/)

  Scientists discovered a strange new type of star that has them puzzled (https://bgr.com/science/scientists-discovered-a-strange-new-type-of-star-that-has-them-puzzled/)

Scientists claim hairy black holes explain Hawking paradox (https://www.bbc.com/news/science-environment-60708711)

Our universe may have a twin that runs backward in time (https://www.livescience.com/mirror-universe-explains-dark-matter) 

Quote
An anti-universe running backwards in time could explain dark matter and cosmic inflation.

  Mysterious invisible walls may have been discovered in outer space (https://bgr.com/science/mysterious-invisible-walls-may-have-been-discovered-in-outer-space/) 

Quote
Scientists suspect that a "fifth force" may be at work in space. This force, which they believe is mediated by a hypothetical particle called a symmetron is responsible for creating invisible walls in space.

 Stellar hypoxia may help make more massive black holes  (https://www.syfy.com/syfy-wire/bad-astronomy-lower-oxygen-in-a-star-may-explain-massive-black-holes)

NASA's Webb Delivers Deepest Infrared Image of Universe Yet (https://www.nasa.gov/image-feature/goddard/2022/nasa-s-webb-delivers-deepest-infrared-image-of-universe-yet)

Earth Is Spinning Faster Than Usual, Leading to the Shortest Day Ever Recorded (https://www.popularmechanics.com/science/environment/a40773059/shortest-day-on-earth/)

At Long Last, Mathematical Proof That Black Holes Are Stable (https://www.quantamagazine.org/black-holes-finally-proven-mathematically-stable-20220804/)

Solving the Hawking Paradox: What Happens When Black Holes Die? (https://www.popularmechanics.com/science/a40847455/hawking-paradox/)

Šta nam rade...

  The Big Bang didn't happen  (https://iai.tv/articles/the-big-bang-didnt-happen-auid-2215)

Quote

The Big Bang Hypothesis - which states the universe has been expanding since it began 14 billion years ago in a hot and dense state - is contradicted by the new James Webb Space Telescope images, writes Eric Lerner.

 Just how massive can stars get? Maybe not *quite* as massive as we thought  (https://www.syfy.com/syfy-wire/bad-astronomy-new-images-of-star-r136a-show-it-to-be-200-times-the-suns-mass)

Black holes could give us clues about dark energy (and the expanding universe). (https://canadatoday.news/ca/black-holes-could-give-us-clues-about-dark-energy-and-the-expanding-universe-71723/)

Strange quark star may have formed from a lucky cosmic merger (https://www.space.com/strange-quark-stars-from-neutron-star-mergers) 

Quote
But there might be a path using strange quarks. By themselves, strange quarks are pretty heavy, and when they're left alone, they rapidly decay into the lighter up and down quarks. When large numbers of quarks group together, however, the physics may change. Physicists have found that strange quarks can bind with up and down quarks to form triplets, known as "strangelets," that might be stable — but only under extreme pressures. Like the pressures one step above a neutron star.

Behavior of star clusters challenge Newton's laws of gravity (https://www.jpost.com/science/article-720979)

The Latest James Webb Image Reveals New Clues About the Origins of the Universe (https://time.com/6246973/james-webb-telescope-stars-origins-of-universe/) 

  We Exist Inside a Giant Space Bubble, And Scientists Have Finally Mapped It (https://www.vice.com/en/article/qjkqbq/we-exist-inside-a-giant-space-bubble-and-scientists-have-finally-mapped-it) 

Quote

Scientists unveiled the first "3D map of a magnetic field over a superbubble," a structure made by exploding stars that contains the solar system.

Wait ... Did We Finally Find the Source of Dark Energy?!  (https://www.popularmechanics.com/space/a42941836/scientists-find-source-of-dark-energy/)



Scientists find first evidence that black holes are the source of dark energy (https://phys.org/news/2023-02-scientists-evidence-black-holes-source.html)

Scientists have "discovered the impossible" –  and it could change everything we know about the dawn of the universe (https://www.cbsnews.com/news/scientists-have-discovered-the-impossible-galaxies-dawn-of-the-universe/)


Uh, James Webb Found Some Galaxies That Technically Shouldn't Exist  (https://www.popularmechanics.com/space/deep-space/a43026293/jwst-discovers-impossible-galaxies/)



Uzbudljivo!!!!!

Stephen Hawking's famous black hole paradox may finally have a solution (https://www.livescience.com/stephen-hawkings-famous-black-hole-paradox-may-finally-have-a-solution)

Scientists Say They've Finally Solved Stephen Hawking's Black Hole Paradox   (https://www.popularmechanics.com/space/deep-space/a43519907/black-hole-paradox-stephen-hawking-finally-solved/)

(Or not)

The most powerful black holes in the universe may finally have an explanation (https://www.livescience.com/space/black-holes/the-most-powerful-black-holes-in-the-universe-may-finally-have-an-explanation)

Researchers May Have Spotted a Star Made of Dark Matter. If So, That's Crazy. (https://www.popularmechanics.com/space/deep-space/a44007686/star-made-of-dark-matter-possible/)

Scientists May Have Finally Heard the 'Hum' of the Big Bang (https://www.thedailybeast.com/gravitational-wave-background-detected-by-astronomers-in-groundbreaking-discovery)

Dark matter power: James Webb telescope may have proven the existence of giant dark stars (https://www.salon.com/2023/07/16/dark-matter-power-james-webb-telescope-may-have-proven-the-existence-of-giant-dark-stars/)

Invisible supernovas called 'bosenovas' may be exploding all around us, new research suggests (https://www.livescience.com/physics-mathematics/dark-matter/invisible-supernovas-called-bosenovas-may-be-exploding-all-around-us-new-research-suggests)

Šta nam rade:


We Could Be Living in a Holographic Universe, a Cosmologist Says (https://www.popularmechanics.com/space/a44269774/holographic-universe/)

Bonus:

How Darwinian Evolution Influenced Stephen Hawking's Theory on the Holographic Universe (https://www.popularmechanics.com/space/deep-space/a44504595/holographic-universe-stephen-hawking-final-theory/)

Откуд сад ово, мислим како се актуелизовало, идеја о холограму је толико стара да су јој деца поднела захтев за пензију.

Are tiny black holes hiding within giant stars? (https://www.science.org/content/article/are-tiny-black-holes-hiding-within-giant-stars)

Svi smo do sada kolektivno verovali da Uran i Neptun imaju različite boje. Da je Uran svetlo-plav, skoro pa beo, a da je Neptun tamno-plav. Ali to nije slučaj. Zapravo su oba svetlo-skoro-pa-belo-plava.

Neptune is not as blue as we all thought! - Reprocessed Voyager 2 images (https://youtu.be/zKSWcFCMrGU)

Scientists may have discovered the most powerful particle collider in the universe (https://www.livescience.com/space/astronomy/scientists-may-have-discovered-the-most-powerful-particle-collider-in-the-universe)

QuoteAstronomers have long suspected that the explosive deaths of massive stars may be responsible for these extremely powerful cosmic rays. After all, these supernovas have all the right ingredients: There is a detonation with more than enough energy, a flood of elementary particles, and magnetic fields that can drive those particles into a frenzy before releasing them into the cosmos.

But observations of nearby supernova remnants such as Tycho and Cassiopeia A have not met expectations; the cosmic rays coming from those places are far weaker than expected.

In a paper accepted for publication (https://arxiv.org/abs/2504.20601) in the journal Astronomy & Astrophysics, researchers have rescued the supernova hypothesis and found that, in special cases, supernova remnants are indeed capable of becoming "PeVatrons" — that is, explosions capable of generating PeV cosmic rays.