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Organic compounds of unexpected complexity exist throughout the universe, Prof. Sun Kwok and Dr. Yong Zhang of the University of Hong Kong have discovered, suggesting that complex organic compounds can be synthesized in space even when no life forms are present. The organic substance they found contains a mixture of aromatic (ring-like) and aliphatic (chain-like) components that are so complex, their chemical structures resemble those of coal and petroleum. Since coal and oil are remnants of ancient life, this type of organic matter was thought to arise only from living organisms. Unidentified radiation from the universe The researchers investigated an unsolved phenomenon: a set of infrared emissions detected in stars, interstellar space, and galaxies, known as "Unidentified Infrared Emission features." From observations taken by the Infrared Space Observatory and the Spitzer Space Telescope, Kwok and Zhang showed that the astronomical spectra have chemical structures that are much more complex that previously thought. By analyzing spectra of star dust formed in exploding stars called novae, they show that stars are making these complex organic compounds on extremely short time scales of weeks, and ejecting it into the general interstellar space, the region between stars. "Our work has shown that stars have no problem making complex organic compounds under near-vacuum conditions," says Kwok. "Theoretically, this is impossible, but observationally we can see it happening." Most interestingly, this organic star dust is similar in structure to complex organic compounds found in meteorites. Since meteorites are remnants of the early Solar System, the findings raise the possibility that stars enriched the early Solar System with organic compounds. The early Earth was subjected to severe bombardments by comets and asteroids, which potentially could have carried organic star dust. Whether these delivered organic compounds played any role in the development of l

Complete video at: http://fora.tv/2009/05/23/Marcus_Chown_in_Conversation_with_Fred_Watson Marcus Chown, author of Quantum Theory Cannot Hurt You: A Guide to the Universe, discusses the mechanics behind quantum computers, explaining that they function by having atoms exist in multiple places at once. He predicts that quantum computers will be produced within 20 years. ----- The two towering achievements of modern physics are quantum theory and Einsteins general theory of relativity. Together, they explain virtually everything about the world in which we live. But almost a century after their advent, most people havent the slightest clue what either is about. Radio astronomer, award-winning writer and broadcaster Marcus Chown talks to fellow stargazer Fred Watson about his book Quantum Theory Cannot Hurt You. - Australian Broadcasting Corporation Marcus Chown is an award-winning writer and broadcaster. Formerly a radio astronomer at the California Institute of Technology, he is now cosmology consultant of the weekly science magazine New Scientist. The Magic Furnace, Marcus' second book, was chosen in Japan as one of the Books of the Year by Asahi Shimbun. In the UK, the Daily Mail called it "a dizzy page-turner with all the narrative devices you'd expect to find in Harry Potter". His latest book is called Quantum Theory Cannot Hurt You.

Looking almost 11 billion years into the past, astronomers have measured the motions of stars for the first time in a very distant galaxy and clocked speeds upwards of one million miles per hour, about twice the speed of our Sun through the Milky Way. The fast-moving stars shed new light on how these distant galaxies, which are a fraction the size of our Milky Way, may have evolved into the full-grown galaxies seen around us today. The results will be published in the August 6, 2009 issue of the journal Nature, with a companion paper in the Astrophysical Journal.

Using entire galaxies as lenses to look at other galaxies, researchers have a newly precise way to measure the size and age of the universe and how rapidly it is expanding, on a par with other techniques. The measurement determines a value for the Hubble constant, which indicates the size of the universe, and confirms the age of the universe as 13.75 billion years old, within 170 million years. The results also confirm the strength of dark energy, responsible for accelerating the expansion of the universe.

SpaceEngine - is a free space simulation software that lets you explore the universe in three dimensions, starting from planet Earth to the most distant galaxies. Areas of the known universe are represented using actual astronomical data, while regions uncharted by human astronomy are generated procedurally. Millions of galaxies, trillions of stars, countless planets!

In our Universe, a black hole is bounded by a spherical surface called an event horizon. Whereas in ordinary three-dimensional space it takes a two-dimensional object (a surface) to create a boundary inside a black hole, in the bulk universe the event horizon of a 4D black hole would be a 3D object - a shape called a hypersphere. When Afshordi's team modelled the death of a 4D star, they found that the ejected material would form a 3D brane surrounding that 3D event horizon, and slowly expand. The authors postulate that the 3D Universe we live in might be just such a brane - and that we detect the brane's growth as cosmic expansion. "Astronomers measured that expansion and extrapolated back that the Universe must have begun with a Big Bang - but that is just a mirage," says Afshordi.

Just days after NASA released the first cosmic dreamscapes taken by the newly refurbished Hubble Space Telescope three teams of astronomers have used the rejuvenated observatory to find what appears to be a bounty of the most distant galaxies known.

Astronomers' new observations have spotted the most distant galaxy ever seen. The galaxy's light comes from about 13.1 billion light-years away, making it one of the first galaxies to form after the Big Bang.

The seasonal ice cap at the South Pole (the one made of dry ice) is evaporating as Astronomers at the University of Arizona watch. A brief discussion of the geology that results.

A celestial audit suggests that astronomers' inventory of luminous bodies may soon be complete (reprint of 3/02 article)

Astronomers have found a new way to search for high-energy cosmic rays, the most energetic particles in the universe, by scanning the face of the Moon.

New experiments have revealed tantalizing evidence that sterile neutrinos are not only real but common. Some of them could even be the stuff of the mysterious dark matter astronomers have puzzled over for decades.

For several decades, astronomers and cosmologists have been piling up data that indicates most of the matter in the Universe is dark, interacting only via gravity. As modified theories of gravity failed to account for observation, candidates for dark mater were winnowed down until one remained in favor: the weakly interactive massive particle, or WIMP. Over the past several years, potential signals of WIMPs have appeared in space and on Earth; that, combined with the startup of the LHC, has given the research community the sense that it's close to pinning down the identity of the WIMPs. But a review in this week's Nature considers what might happen if we fail.

The Bolshoi simulation is the most accurate cosmological simulation of the evolution of the large-scale structure of the universe yet made ("bolshoi" is the Russian word for "great" or "grand").  The first two of a series of research papers describing Bolshoi and its implications have been accepted for publication in the Astrophysical Journal. The first data release of Bolshoi outputs, including output from Bolshoi and also the BigBolshoi or MultiDark simulation of a volume 64 times bigger than Bolshoi, has just been made publicly available to the world's astronomers and astrophysicists.

Captured by NASA's Chandra X-ray Observatory and combined with data from infrared and optical telescopes, this image shows the farthest galaxy cluster ever detected. Designated JKCS041, the cluster is located 10.2 billion light-years from Earth, beating the previous distance record by a billion light-years. Astronomers think JKCS041 formed just about as early as was feasible.

Just days after NASA released the first cosmic dreamscapes taken by the newly refurbished Hubble Space Telescope three teams of astronomers have used the rejuvenated observatory to find what appears to be a bounty of the most distant galaxies known.

ScienceDaily (Sep. 12, 2011) - The HARPS spectrograph on the 3.6-metre telescope at ESO's La Silla Observatory in Chile is the world's most successful planet finder [1]. The HARPS team, led by Michel Mayor (University of Geneva, Switzerland), have announced the discovery of more than 50 new exoplanets orbiting nearby stars, including sixteen super-Earths [2]. This is the largest number of such planets ever announced at one time [3]. The new findings are being presented at a conference on Extreme Solar Systems where 350 exoplanet experts are meeting in Wyoming, USA.