A Planetary System That Never Was Teaches About Those That May Be. Want to stay on top of all the space news? Follow @universetoday on Twitter While Kepler and similar missions are turning up planets by the fist full, there’s long been many places that astronomers haven’t expected to find planetary systems. The main places include regions where gravitational forces conspire to make the region around potential host stars too unstable to form into planets.
And there’s no place in the galaxy with a larger gravitational force than the galactic center where a black hole four and a half million times more massive than the Sun, lurks. But a new study shows evidence that a disk, potentially far enough along to begin forming planets, is in the process of being disrupted. The new study investigates an ionized cloud of gas discovered earlier this year, plummeting in towards the black hole. However, such massive stars are able to determine an age limit for the group, which has been set somewhere between 4-8 million years. About Jon Voisey. The Cosmic Magnifying Lens | Degrees of Freedom. Objects may be closer than they appear; in the distant universe, objects are, in a sense, even farther than they appear The observable universe is one big, giant magnifying lens.
At large distances, objects appear to be larger than their true size, and the farther they are, the bigger they look. The most distant observable objects are so magnified that their images in the sky—if we could see them—would be blown up by a factor of 1,000 or more. If there were a road leading from here to the edge of the universe, you wouldn’t see it getting smaller and smaller and finally converge to a point, the way you see straight roads on earth vanish to a point on the horizon, as in the picture above. Instead, you’d see the two shoulders get closer for a while, reach a minimum width, and then start moving apart again. To get some visual intuition about what happens then, it is helpful to look at the technique that artists have codified as reverse perspective, also known as Byzantine perspective. Starbursts May Actually Destroy Globular Clusters. Want to stay on top of all the space news? Follow @universetoday on Twitter The Galactic globular cluster M80 in the constellation Scorpius contains several hundred thousand stars.
Credit: HST/NASA/ESA It seems logical to assume that long ago, the amount of globular clusters increased in our galaxy during star-making frenzies called ‘starbursts.’ But a new computer simulation shows just the opposite: 13 billion years ago, starbursts may have actually destroyed many of the globular clusters that they helped to create. “It is ironic to see that starbursts may produce many young stellar clusters, but at the same time also destroy the majority of them,” said Dr. The new computer simulation by Kruijssen and his team proposes that this difference could be explained by the conditions under which globular clusters formed early on in the evolution of their host galaxies.
In the early Universe, starbursts were common. Source: Max-Planck Institute for Astrophysics. Astrophile: Square galaxy is a rebel - physics-math - 21 March 2012. Astrophile is our weekly column on curious cosmic objects, from the solar system to the far reaches of the multiverse Object type: Dwarf galaxyLocation: Eridanus constellation If a person is square they are a bit dull, but for a galaxy, it is the mark of a true rebel. A rectangular galaxy spotted 70 million light years from Earth is the boxiest galaxy known – and could bring a new understanding of how galaxies form and evolve. Galaxies take on one of three shapes: a flattened circular disc typically hosting a spiral pattern of stars like our Milky Way, an ellipsoid – like a rugby ball or American football – or an irregular shape without clear symmetry.
Box-like galaxies are virtually unheard of, says Alister Graham at the Swinburne University of Technology in Hawthorn, Victoria, Australia. "It's one of those things that just makes you smile because it shouldn't exist, or rather, you don't expect it to exist," says Graham. Side-on cylinder If it is a cylinder, how might it be formed? Visible Echoes Reprise 19th Century Spectacle. Fresh Start: Scientists Glimpse Unsullied Traces of the Infant Universe. By peering into the distance with the biggest and best telescopes in the world, astronomers have managed to glimpse exploding stars, galaxies and other glowing cosmic beacons as they appeared just hundreds of millions of years after the big bang. They are so far away that their light is only now reaching Earth, even though it was emitted more than 13 billion years ago. Astronomers have been able to identify those objects in the early universe because their bright glow has remained visible even after a long, universe-spanning journey.
But spotting the raw materials from which the first cosmic structures formed—the gas produced as the infant universe expanded and cooled in the first few minutes after the big bang—has not been possible. Now a group of researchers reports identifying the first known pockets of pristine gas, two relics of those first minutes of the universe's existence. Universe's first stars not so big after all - space - 10 November 2011.
The universe's earliest stars may have been less than half as large as previously thought, according to two new simulations. The findings could resolve one of the universe's oldest mysteries: why some elements are more abundant than our theories suggest they should be. In the first hundreds of millions of years after the big bang, the early universe was composed mainly of atomic hydrogen, helium and tiny amounts of other light elements. Eventually clouds of these gases condensed into the first stars, but without dust, heavy elements, or molecules, these early stars were unable to cool down as quickly as their descendents. In 2008, Christopher McKee of the University of California, Berkeley, and colleagues derived a model suggesting that these early stars would grow to between 100 and 200 times the mass of our sun before the heat they gave off made the surrounding gas too energetic to pull any more gas in and accrete further.
Subsequent simulations bolstered this claim Hot fuss . Baby pulsars spawn universe's most energetic particles - space - 01 February 2012. Talk about enfants terribles. Baby pulsars may unleash torrents of the highest energy particles known, explaining the provenance of the ultra-high-energy cosmic rays that hit Earth. Charged particles with energies of at least 1019 electronvolts slam into our atmosphere from time to time – since 2008, 5000 have been detected by the Auger observatory in Argentina.
Their source has been a mystery. Pulsars – ultradense stars formed during supernova blasts – are one candidate, but it has not been clear if the particles they shed could make it through the dense shroud of stellar shrapnel that surrounds them. Now Ke Fang and colleagues at the University of Chicago have modelled these particles and found that they can escape within the first year of a pulsar's life. At that time, the pulsar's spin, which gradually slows, is still fast enough to shoot out high-energy particles, and the supernova debris has spread out enough to allow those particles to escape. 'Violent fellows' Nearby pulsar (YouTube)
Hubble Spots Mysterious Dark Matter ‘Core’ Want to stay on top of all the space news? Follow @universetoday on Twitter This composite image shows the distribution of dark matter, galaxies, and hot gas in the core of the merging galaxy cluster Abell 520, formed from a violent collision of massive galaxy clusters. Image Credit: NASA, ESA, CFHT, CXO, M.J. Jee (University of California, Davis), and A. Mahdavi (San Francisco State University) Astronomers are left scratching their heads over a new observation of a “clump” of dark matter apparently left behind after a massive merger between galaxy clusters. Initially, the observations made in 2007 were dismissed as bad data. “This result is a puzzle,” said astronomer James Jee (University of California, Davis). Current theories on dark matter state that it may be a kind of gravitational “glue” that holds galaxies together. Studies of Abell 520 are causing astronomers to think twice about our current understanding of dark matter.
Tagged as: Abell 520, Hubble Space Telescope. Distant Invisible Galaxy Could be Made Up Entirely of Dark Matter. Want to stay on top of all the space news? Follow @universetoday on Twitter The gravitational lens B1938+666 as seen in the infrared when observed with the 10-meter Keck II telescope. Credit: D. Lagattuta / W. M. Keck Observatory Astronomers can’t see it but they know it’s out there from the distortions caused by its gravity. “Now we have one dark satellite [galaxy],” said Simona Vegetti, a postdoctoral researcher at the Massachusetts Institute of Technology, who led the discovery. They found two galaxies aligned with each other, as viewed from Earth, and the nearer object’s gravitational field deflected the light from the more distant object (JVAS B1938 + 666) as the light passed through the dark galaxy’s gravitational field, creating a distorted image called an “Einstein Ring.” Using data from this effect, the mass of the dark galaxy was found to be 200 million times the mass of the Sun, which is similar to the masses of the satellite galaxies found around our own Milky Way.
Astronomers Discover Ancient Planetary System. Want to stay on top of all the space news? Follow @universetoday on Twitter Artist’s impression of HIP 11952 and its two Jupiter-like planets. Image credit: Timotheos Samartzidis From a press release from the Max Planck Institute for Astronomy: A group of European astronomers has discovered an ancient planetary system that is likely to be a survivor from one of the earliest cosmic eras, 13 billion years ago.
The system consists of the star HIP 11952 and two planets, which have orbital periods of 290 and 7 days, respectively. Whereas planets usually form within clouds that include heavier chemical elements, the star HIP 11952 contains very little other than hydrogen and helium. This suggests a key question: Originally, the universe contained almost no chemical elements other than hydrogen and helium. For classical models of planet formation, which favor metal-rich stars when it comes to forming planets, planets around such a star should be extremely rare. Astrophile: The planets that formed by cell division - space - 02 April 2012. Read full article Continue reading page |1|2 Objects: Rocky planets KOI 55.01 and KOI 55.02Size: 0.759 and 0.867 times Earth's diameterDistance: 4000 light years from Earth When the sun-like star KIC 05807616 ran out of hydrogen, its planets thought they were done for.
The star began puffing off its outer layers, and over the next billion years, ballooned up into a red giant a million times its original volume. Most of its planets were probably lost in the process, swallowed up by the star and never seen again. If it could just hang on until the star's outer layers swept back over it as they collapsed onto the star again, triggering helium fusion, maybe it would make it. "Some of [the pieces] did not survive, and fell into the star," says Noam Soker at the Technion – Israel Institute of Technology in Haifa. Those two pieces – each a little smaller than Earth – are still in orbit around the star, say Soker and Ealeal Bear, also at Technion – Israel. Strangely small Synchronised orbits. When 14 Billion Years Just Isn't Enough Time. Time’s seemingly inexorable march has always provoked interest in, and speculation about, the far future of the cosmos. The usual picture is grim. Five billion years from now the sun will puff itself into a red giant star and swallow the inner solar system before slowly fading to black.
But this temporal frame captures only a tiny portion—in fact, an infinitesimal one—of the entire future. As astronomers look ahead, say, “five hundred and seventy-six thousand million years,” as humorist Douglas Adams did in The Restaurant at the End of the Universe, they meet a cosmos replete with myriad slow fades to oblivion. By then the accelerating expansion of space will have already carried everything outside our galaxy beyond our view, leaving the night sky ever emptier. But here’s the good news: oncoming darkness captures only half the story. Select an option below: Customer Sign In *You must have purchased this issue or have a qualifying subscription to access this content. The History of the Universe: From Big Bang to Big Blah. Space::Web Exclusives::February 20, 2012:: ::Email::Print Today's universe may not be as rip-roaring as the primordial cosmos, but remains an action-packed place Image: After the furies of birth, the mature cosmos now evolves more slowly.
Stars will continue to form for as long as another 100 trillion years (about 10,000 times the present age of the universe), which leaves plenty of time for slow-building cosmic phenomena to occur. » View the timeline. Our Early Universe: Inflation, or Something Totally Wacky? Want to stay on top of all the space news? Follow @universetoday on Twitter A schematic look at the universe - where it came from and where it is now. Credit: NASA. Astronomers generally accept the theory that our universe looks the way it does because of cosmic inflation — rapid expansion in the moments after its birth. This explains the expanse and apparent flat shape of the universe observed through instruments like NASA’s Wilkinson Microwave Anisotropy Probe. But inflation isn’t the only model that explains the early universe. There are others, and they get wacky. Three physicists from the University at Buffalo — Ghazal Geshnizjani, Will Kinney and Azadeh Moradinezhad Dizgah — set out to investigate other cosmic models.
This picture of the infant universe from NASA's Wilkinson Microwave Anisotropy Probe (WMAP) reveals 13 billion+ year old temperature fluctuations that correspond to the seeds that grew to become the galaxies. The takeaway message? Source: The University of Buffalo. Naked black-hole hearts live in the fifth dimension - physics-math - 13 January 2012. Read more: "Why physicists can't avoid a creation event" "IT SEEMS very rude to come to someone's party and tell him that he lost a bet again," said cosmologist Luis Lehner of the Perimeter Institute in Ontario, Canada.
Lehner did it anyway. He was speaking at a meeting to celebrate Stephen Hawking's 70th birthday. The bet in question was over whether a point of infinite density and space-time curvature, known as a singularity and usually found at the centre of a black hole, can also exist in a naked form without its black hole. At a singularity, all our existing physical laws go out the window. Near a naked singularity, however, things would become bewildering as we would no longer be able to predict the fate of anything in its line of sight.
In 1991, Hawking bet Kip Thorne and John Preskill of the California Institute of Technology in Pasadena that all singularities are clothed. Thorne, the beneficiary of the bet, was in the audience and said the study was "beautiful work". Goldilocks Black Holes. Big Gulp: Flaring Galaxy Marks the Messy Demise of a Star in a Supermassive Black Hole. NASA | X-ray 'Echoes' Probe Habitat of Monster Black Hole. Black Holes are Everywhere | Life, Unbounded. Black Holes are More Like Venus Fly Traps than Vacuum Cleaners. Early Black Holes were Grazers Rather than Glutonous Eaters. Speca – An Intriguing Look Into The Beginning Of A Black Hole Jet. Two (or three?) black holes in one galactic center. Black holes as particle detectors. Supernova Explosions, Black Hole Jets Might Cause Galaxies to ‘Age’ Faster.
Pulsar heavyweight champ challenges Einstein - space - 16 May 2012. Antimatter-Powered Supernovae. Iron in the Fire: The Little-Star Supernovae That Could. UC Berkeley Press Release. Top 24 Deep Space Pictures of 2011. Stellar Superflares' Trigger Challenged. Some Newfound Planets Are Something Else. Does a galaxy filled with habitable planets mean humanity is doomed?
Diamond planets may not be life's best friend - space - 06 December 2011. Dust rings not 'smoking gun' for planets after all - space - 14 May 2012. Giant Celestial Disk Hard To Explain. Rogue Planets Can Find Homes Around Other Stars. Astrophile: Runaway is star of cosmic whodunnit - physics-math - 15 June 2012. Smallest planet is tinier than Earth - space - 20 December 2011. Planet found at perfect spot for life - in solar system with three suns. Two new Earth-sized exoplanets discovered. Light From a ‘SuperEarth’ Detected for the First Time. Infographic: The New Planetary Habitability Index. An Abundance of Exoplanets Changes our Universe | Life, Unbounded. Searching for Exoplanet Oceans More Challenging Than First Thought. Alien Planets May Thrive on Many Wavelengths of Light. Hell off Earth: Blustery Exoplanet Charted in 2-D for First Time. New Evidence For Fomalhaut Planets. Disruptive Planets and their Consequences.
Astrophile: Attack of the mystery green blobs - space - 04 November 2011. Astrophile: Wounded galaxy is crux of cosmic whodunnit - space - 09 December 2011. Frantic Comet Massacre Taking Place at Fomalhaut. Astrophile: The case of the disappearing pulsar - space - 21 May 2012. Scientists Discover The Oldest, Largest Body Of Water In Existence--In Space. Monster Black Holes Are Most Massive Ever Discovered. 20 million mph winds seen blowing from black hole. Will This Be The End Of The Earth? 589217_scale_of_universe_enhanced.swf (application/x-shockwave-flash Object)
Planck mission steps closer to the cosmic blueprint. “Impossible” Binary Star Systems Found.