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The Last Month in Astronomy


DEC-10-2011 • Lunar Eclipse • A lunar eclipse was seen by most of the United States on December 10. On the west coast the eclipse left totality about the same time the moon set. Follow this link to find a large variety of pictures of the lunar eclipse.

DEC-09-2011 • Largest Telescope • If you were to guess the size of the largest telescope what would you say? 8 meters, 10 meters, 30 meters. Would you believe 360,000 kilometers? You can guess that this means a radio astronomy telescope. Multiple radio astronomy telescopes can create a long baseline for interferometry. When dishes in Germany, Ukraine and Russia are used with the Spektr-R spacecraft a baseline equal to 30 Earth diameters is created. This gives a resolution as fine as 1/100,000 arcsecond.

DEC-07-2011 • Opportunity checks vein • The Mars Rover Opportunity has found a mineral vein of calcium sulfate. This can exist in many forms depending on how much water is bound into the crystalline structure. In this case the substance appears to by gypsum, the same substance that is used for making drywall. Previous orbital observations had detected gypsums in dunes that look similar to the white sands in New Mexico. It is unknown where this vein of material came from. Steve Squyres, the Rover’s PI, says “This gypsum vein is the single most powerful piece of evidence for liquid water at Mars that has been discovered by the Opportunity Rover.”

DEC-05-2011 • Fastest spinning star • Probably all stars rotate. One star has been detected spinning at the rate of 1 million miles per hour. This is 300 times the speed of our sun’s rotation. That star, VFTS 102, is located in the Large Magellanic Cloud. It might be the near the speed at which a star can rotate without being torn apart by the centrifugal forces. It might itself be the result of a stellar explosion by its binary counterpart.

DEC-02-2011 • 18 new exoplanets • 18 new exoplanets have been discovered using the wobble method by Caltech astronomers using the Keck Telescopes. It is the biggest single announcement of new planets other than from Kepler. These planets are around A type stars that are more than 1.5 times the size of the sun. In addition, these stars are just about to leave the main sequence.

DEC-01-2011 • More Gamma-Ray Sources • NASA’s Fermi Gamma-Ray Space Telescope has found many sources of gamma rays. Some are the expected: supernova remnants, active galactic nuclei. But some are emitted by objects that have not been detected at any other wavelength. Of the 1873 sources identified by Fermi, about one third are unknown. One example is near the galactic plane suggesting it is a source within the galaxy instead of far away. The breakdown of all sources goes like this: Blazers 57%; Unknown 31%; Pulsars 6%; Supernova remnants 4%; Miscellaneous 2%.

NOV-29-2011 • Phobos-Grunt • No, that isn’t the name of a rude sound, it’s the name of a Russian Mars probe that made it into Earth orbit but that’s all. It is expected to fall to Earth in January. A Dutch astronomer used his 10” scope to capture an image of the stricken spacecraft. On December 13, a spokesman for the company that built the spacecraft called it a failure and “Mission Impossible”. The spacecraft is expected to break up during reentry in mid-January and no parts should reach the Earth including the 7.5 tons of dangerous rocket fuel (Hydrazine).

NOV-26-2011 • Curiosity to Mars • The most ambitious robotic spacecraft ever launched is on its way to Mars. The Mars Science Laboratory was launched aboard an Atlas V rocket. A midcourse maneuver planned for early December has been postponed because the launch-time accuracy was so good.

NOV-16-2011 • Europa and liquid water • The Galileo spacecraft was launched from the Space Shuttle back in 1989 and it has been years since it was deliberately dropped into Jupiter. But data from that mission is still paying dividends. One example of that is the evidence for liquid water on Europa. Analysis suggests the chaotic features may be formed as a result of an exchange between that moon’s icy shell and liquid water that lies beneath. “The data open up some compelling possibilities” according Mary Voytek, director of NASA’s Astrobiology Program. Britney Schmidt, lead author of this new study, said “One opinion in the scientific community has been if the ice shell is thick, that’s bad for biology ... [but] now we see evidence that it’s a thick ice shell that can mix vigorously ... that could make Europa and its ocean more habitable.”


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