Ghostly gamma-ray beams blast from Milky Way's center (Phys.org) -- As galaxies go, our Milky Way is pretty quiet. Active galaxies have cores that glow brightly, powered by supermassive black holes swallowing material, and often spit twin jets in opposite directions. In contrast, the Milky Way's center shows little activity. "These faint jets are a ghost or after-image of what existed a million years ago," said Meng Su, an astronomer at the Harvard-Smithsonian Center for Astrophysics (CfA), and lead author of a new paper in the Astrophysical Journal. "They strengthen the case for an active galactic nucleus in the Milky Way's relatively recent past," he added. The two beams, or jets, were revealed by NASA's Fermi space telescope. The newfound jets may be related to mysterious gamma-ray bubbles that Fermi detected in 2010. "The central accretion disk can warp as it spirals in toward the black hole, under the influence of the black hole's spin," explained co-author Douglas Finkbeiner of the CfA. The two structures also formed differently.
Cave Of Forgotten Dreams Updates: Our asteroid belt is unique -- and that’s why life may be rare in the Galaxy By George Dvorsky Our asteroid belt, which is situated between Jupiter and Mars, has traditionally been seen as something of a nuisance. Every once in awhile one of these rocks dislodges itself and heads straight for Earth, what often results in a cataclysmic impact. But ironically, as a new study from the University of Colorado suggests, we may owe our very existence to these chunks of displaced rocks. Astronomers and astrobiologists are increasingly coming to see asteroid belts as an important component to solar system composition, planet formation, and the emergence of life. Despite the astronomical chaos produced by impact events, asteroids delivered water, organic compounds, and heavy elements to Earth — what are all crucial for the emerge of life. And according to researchers Rebecca Martin (University of Colorado) and Mario Livio (Space Telescope Science Institute in Baltimore, Md.), not every solar system has an asteroid belt like ours — and not by a long shot.
A New Equation Reveals Our Exact Odds of Finding Alien Life I find it beyond weird that these supposedly smart people never factor time into the equation. If you miss someone by a minute or a millennium, you've still missed them. Even assuming a habitable world chemically, radiationally and biologically identical to Earth where evolution matched Earth's right up until the rise of humans, we still could've missed a high tech society by 100,000 years. (Radiationally is totally a word. Now.) There's a good reason for that. So it's good to start with an assumption that we do know: Earth like conditions are necessary* but not sufficient for life. *I mean necessary in the logical sense, as in "In the presence of Earth like conditions, life can happen." Did you miss the "L" factor is the Drake equation? The Drake equation factors in such a variable: "L" the lifespan of an intelligent civilization.
Top 3 Questions People Ask an Astrophysicist (and Answers) Credit: Alain R. | Wikimedia Commons Whether he's teaching class, socializing at a cocktail party or talking to visitors at the planetarium where he works, Charles Liu knows that sooner or later he's going to get asked at least one of three questions: Is there a god? Are there aliens? "I've never been in a public environment where people know what I do where at least one of these questions was not asked," Liu said. Over the years, Liu has developed some pretty solid answers, based on scientific evidence and his own opinion, to those three burning questions. 6 Insane Coincidences You Won't Believe Actually Happened America's Freak Luck During the Battle of Midway The Battle of Midway may be remembered as one of the most spectacular naval battles in history and one of the huge turning points in the Pacific theater, but it started out as a pure clusterfuck for the Americans. Despite going into battle with most of Japan's game plan in their pocket thanks to American codebreakers/Bothan spies, the U.S. Navy had little to show for it in the early hours of June 4, 1942. Just about every aircraft that took on the Japanese that day was destroyed, and all without delivering any serious damage. In short, the Battle of Midway started off like the Battle of Endor, only with every fighter in the Rebel Fleet crashing into the Death Star's deflector shield. Where it Gets Weird: There was one squadron of American dive bombers lead by Lieutenant Commander C. His squadron started dropping like flies until, in an act of sheer luck that would make even J.K. Where it Gets Even Weirder: ...when he wasn't busy being a pimp.
New Technique Could Help Scientists Detect Alien Life... in Four Years Just wait till we turn this thing on, and discover a thousand-plus worlds that seems to have a signal for life. To look up at the stars and know* that all the universe is filled with life, everywhere**. * Obviously I'm using the term loosely here. ** Or, alternately, not. However, I'm one of those people that believe that life is almost inevitable, as are some of the more basic principals, like photosynthesis. if the answer turns out to be 'no', it's the wrong answer. The only sense that I can imagine that the answer would be no, is just that logical part of me that says that has to be a possibility until proven otherwise. But speaking of betting, I would bet almost everything that life is abundant in the universe; and that if it's possible to detect intelligent life on the level I suggested (radioactivity, CFCs, etc), that intelligent life will be detected. * From my new book, "Things to Ponder While You're High." So, life has to be on the planet. * Not proof. * Not a chemist.
Rare Earth hypothesis Hypothesis that complex extraterrestrial life is a very improbable phenomenon and likely to be extremely rare The Rare Earth hypothesis argues that planets with complex life, like Earth, are exceptionally rare In planetary astronomy and astrobiology, the Rare Earth hypothesis argues that the origin of life and the evolution of biological complexity such as sexually reproducing, multicellular organisms on Earth (and, subsequently, human intelligence) required an improbable combination of astrophysical and geological events and circumstances. A contrary view was argued in the 1970s and 1980s by Carl Sagan and Frank Drake, among others. It holds that Earth is a typical rocky planet in a typical planetary system, located in a non-exceptional region of a common barred-spiral galaxy. Requirements for complex life In order for a small rocky planet to support complex life, Ward and Brownlee argue, the values of several variables must fall within narrow ranges. Star metallicity declines. .
Galactic astronomy Galactic astronomy is the study of our own Milky Way galaxy and all its contents. This is in contrast to extragalactic astronomy, which is the study of everything outside our galaxy, including all other galaxies. Galactic astronomy should not be confused with galaxy formation and evolution, which is the general study of galaxies, their formation, structure, components, dynamics, interactions, and the range of forms they take. Our own Milky Way galaxy, where our Solar System belongs, is in many ways the best studied galaxy, although important parts of it are obscured from view in visible wavelengths by regions of cosmic dust. The development of radio astronomy, infrared astronomy and submillimetre astronomy in the 20th Century allowed the gas and dust of the Milky Way to be mapped for the first time. Subcategories A standard set of subcategories is used by astronomical journals to split up the subject of Galactic Astronomy: Stellar populations See also
Teleportation Teleportation is the name given by science fiction writers to the feat of making an object or person disintegrate in one place while a perfect replica appears somewhere else. How this is accomplished is usually not explained in detail, but the general idea seems to be that the original object is scanned in such a way as to extract all the information from it, then this information is transmitted to the receiving location and used to construct the replica, not necessarily from the actual material of the original, but perhaps from atoms of the same kinds, arranged in exactly the same pattern as the original. A teleportation machine would be like a fax machine, except that it would work on 3-dimensional objects as well as documents, it would produce an exact copy rather than an approximate facsimile, and it would destroy the original in the process of scanning it. In 1993 an international group of six scientists, including IBM Fellow Charles H. C.H. Experimental Articles D.
New Tool Coming In Hunt For Alien Life With the James Webb Space Telescope still more than four years away from launch astronomers are coming up with ideas on how to maximise its usefulness. A proposal published in Astrobiology outlines a way it could be used to detect signatures of life on planets around nearby stars. While it is always possible that life around extrasolar worlds will be “not as we know it”, the obvious place to start looking is on planets as similar as possible to our own. This includes the presence of liquid water, which in turn requires a substantial atmosphere. Low atmospheric pressure means water boils as soon as it melts. However, according to the new paper, “Current proposed methods for measuring pressure by using remote-sensing techniques that could be applicable to exoplanetary atmospheres are challenging.” A better way, the authors suggest, is to look for dimers. While knowing the pressure in the atmosphere is important, just picking up O2-O2 dimers could matter for another reason.