Author Topic: Pitanja u vezi sa astronomijom/astrofizikom  (Read 18024 times)

0 Members and 1 Guest are viewing this topic.

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #100 on: 21-01-2016, 13:00:53 »
To je jer je Pluton ražalovan sa statusa planete, okej. Ali bila je tu i "deseta" planeta pre jedno deset godina a očigledno nisam upratio šta je s tim bilo...

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #101 on: 02-02-2016, 06:38:44 »
 Earth Is Made Up Of Two Planets, Say Scientists
 
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 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.

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #102 on: 02-03-2016, 08:50:27 »
Conditions for life may hinge on how fast the universe is 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 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. 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.”

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #103 on: 12-03-2016, 13:46:12 »
Astronomers say they’ve 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.)
  This animated flight through the universe shows close to 400,000 galaxies. (Berkeley Lab) 
Anyway, scientists working for the Baryon Oscillation Spectroscopic Survey — 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, 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 of the Canary Islands Institute of Astrophysics, a lead author on the study, told the New Scientist.
 
  [Astronomers just saw farther back in time than they ever have before]
 
“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. 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,” 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 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]
 
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, an astrophysicist at the University of California at San Diego, told the New Scientist. “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 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.
 

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #104 on: 17-03-2016, 06:15:06 »
Astronomers discovered unexpected activity on a giant asteroid that could point to something huge
 
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 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 in the Monthly Notices of the Royal Astronomical Society.
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.
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.
 


Nightflier

  • Geek Royalty
  • 5
  • 3
  • Posts: 9.788
  • Wolf Who Rules
    • Nightflier's Bookspace
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #106 on: 28-03-2016, 06:22:16 »
Bio je Tajson kod Kolbera pre neki mesec da objašnjava matematiku glede toga...
Sebarsko je da budu gladni.
First 666

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #107 on: 29-03-2016, 05:37:51 »
What Is Dark Matter? Astronomers Are One Step Closer to Understanding Mysterious Phenomena
 
Quote

Astronomers may have detected signatures of elusive 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 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% of the universe, while dark matter makes up 27%. (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, 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 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 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.
 

Harley Quinn

  • Guest
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #108 on: 28-06-2016, 23:11:32 »
Večeras sam otkrila ovaj kanal. I ne mogu da prestanem da ga gledam:


Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #109 on: 11-07-2016, 09:00:30 »
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 released by the university. [Frigid Brown Dwarf May Have Water-Ice Clouds (Video)]
WISE 0855 is five times more massive than Jupiter, making it a brown dwarf—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. "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.
 

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #110 on: 14-07-2016, 07:57:54 »
New Dwarf Planet Discovered in Outer Solar System



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


Astronomers have found another Pluto-like 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

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?
The Minor Planet Center describes RR245 as the 18th largest object in the 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.

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #111 on: 19-07-2016, 07:39:28 »
World’s Most Powerful Radio Telescope Discovers 1300 New Galaxies in Trial Run



Quote
On Saturday night astronomers at the South African MeerKAT radio telescope array 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 (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 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.

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #112 on: 27-10-2016, 08:08:20 »
Curious tilt of the Sun traced to undiscovered planet


Quote
Planet 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," Elizabeth Bailey, Konstantin Batygin and Michael E. Brown, 2016, Astrophysical Journal

Pizzobatto

  • 4
  • 3
  • Posts: 5.631
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #113 on: 13-11-2016, 20:40:42 »

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!
Better a witty fool than a foolish wit

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #114 on: 17-11-2016, 06:10:02 »
  Stephen Hawking Puts An Expiry Date On Humanity 
 
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, 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 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. “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.”
 

Pizzobatto

  • 4
  • 3
  • Posts: 5.631
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #115 on: 17-11-2016, 11:55:18 »
Овај би да побјегне од Трампа! Неће моћи!
Better a witty fool than a foolish wit


Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #117 on: 19-03-2017, 06:54:09 »
 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 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.
When a white dwarf pulls material from another star, the system is described as a cataclysmic variable star. But back in 2015, 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 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 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.
"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 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 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. "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 and you can read it in full at arXiv.org.
   


Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #119 on: 22-05-2017, 08:03:06 »
Odgovor na pitanje iz naslova je, kako nas uči Beteridž, "ne", ali svejedno, ovo je zanimljivo:

Multiverse: have astronomers found evidence of parallel universes?


Аксентије Новаковић

  • 3
  • Posts: 2.512
  • Homo Superior
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #121 on: 10-08-2017, 21:13:12 »
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/




zosko

  • 4
  • 3
  • Posts: 12.895
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #124 on: 12-10-2017, 18:48:01 »
neutron star collision. :roll:
moving on my own trace


Ugly MF

  • 4
  • 3
  • Posts: 4.449
  • Kopernik je prso skroz!
    • http://comicsartist.blogspot.com/
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #126 on: 17-10-2017, 10:37:13 »
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?


Ugly MF

  • 4
  • 3
  • Posts: 4.449
  • Kopernik je prso skroz!
    • http://comicsartist.blogspot.com/
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #128 on: 17-10-2017, 10:51:58 »
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...

scallop

  • 5
  • 3
  • Posts: 23.275
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #129 on: 17-10-2017, 10:59:54 »
Vidim da te nisu zadovoljili. 'Oćeš kratku priču, novelu, roman ili pentologiju?
Never argue with stupid people, they will drag you down to their level and then beat you with experience. - Mark Twain.

Ugly MF

  • 4
  • 3
  • Posts: 4.449
  • Kopernik je prso skroz!
    • http://comicsartist.blogspot.com/
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #130 on: 17-10-2017, 11:15:46 »
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.

mac

  • 3
  • Posts: 9.135
    • http://www.facebook.com/mihajlo.cvetanovic
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #131 on: 17-10-2017, 11:34:00 »
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. 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.

scallop

  • 5
  • 3
  • Posts: 23.275
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #132 on: 17-10-2017, 11:35:04 »
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.
Never argue with stupid people, they will drag you down to their level and then beat you with experience. - Mark Twain.

Ugly MF

  • 4
  • 3
  • Posts: 4.449
  • Kopernik je prso skroz!
    • http://comicsartist.blogspot.com/
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #133 on: 17-10-2017, 12:10:10 »
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.

Meho Krljic

  • 5
  • 3
  • Posts: 44.362
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #134 on: 17-10-2017, 12:29:58 »
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...
 

scallop

  • 5
  • 3
  • Posts: 23.275
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #135 on: 17-10-2017, 12:55:47 »

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.
Never argue with stupid people, they will drag you down to their level and then beat you with experience. - Mark Twain.

Ugly MF

  • 4
  • 3
  • Posts: 4.449
  • Kopernik je prso skroz!
    • http://comicsartist.blogspot.com/
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #136 on: 17-10-2017, 15:35:56 »
Mnjeeeeee....
Ni Mehovi starci ,ni moji goblini, ni tvoj sajfaj nemaju ama baš nikakve veze sa astrofizikom.
To smo se zajebavali, ajmo dalje.

zosko

  • 4
  • 3
  • Posts: 12.895
Re: Pitanja u vezi sa astronomijom/astrofizikom
« Reply #137 on: 17-10-2017, 19:16:06 »
...
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.
moving on my own trace