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The Last Month in Astronomy


JAN-12-2011 •SDSS III• The Sloan Digital Sky Survey has released an enormous picture. How enormous? How about 1.2 trillion (that’s with a “t”) pixels. As soon as you can assemble 500,000 HDTVs into a matrix, you can view it. In the meantime it is better to think of this as a database. Instead of queries you zoom around it.

JAN-12-2011 •Kepler 10b• The Kepler spacecraft has discovered a rocky planet that is close to Earth-size. It is about 40% bigger than Earth but it is much too close to its star to be a likely holder of life. Its orbit is less than a day. Kepler 10 is a star that is very well studied, perhaps the best known of all the stars that have exoplanets.

JAN-12-2011 •M1 Dimming• The Crab Nebula (M1) is apparently dimming. The gamma rays (around .001 nanometers) from the nebula have diminished by about 7%. That’s a surprise because the nebula has long been thought to be a standard candle. The measurements were made by ESA International Gamma-Ry Astrophysics Laboratory (INTEGRAL), NASA’s Swift Burst Alert Telescope and Rossi X-Ray Timing Explorer (RXTE) and NASA’s Fermi Gamma-Ray Burst Monitor (GBM). The Crab Nebula is the remnant of a supernova that was seen on Earth in 1054. It has a pulsar (spinning neutron star) at its core but the dimming is due to the nebula.

JAN-06-2011 •AGNs not created by collisions• Active Galactic Nuclei (AGN) are powered by blackholes that are busy chowing down in the middle of distant galaxies. But what created the blackhole? It was thought the galactic collisions created the conditions necessary to create the blackholes but new data suggests that is the more rare case. Something else must be causing most of these AGNs such as local instabilities in the galaxy, large molecular clouds, or tidal disruption caused by near misses between galaxies.

JAN-05-2011 •10 yr. old finds SN• A girl age 10 has become the youngest person in the world to discover a supernova. Images taken at an amateur observatory were used and compared to previous images find the 17 magnitude star “blinking”. Her father, an amateur astronomer, helped by ruling out asteroids and current supernovas. The supernova occurred in galaxy UGC 3378 in the constellation Camelopardalis.

JAN-04-2011 •Organics on Mars• Christopher McKay (NASA Ames) says “It’s like a 30 year-old cold case suddenly solved with new facts.” One new fact was that the Phoenix Martian Laboratory found perchlorate in the soil. The second new fact is that scientists repeated an experiment done by the Viking Martian lander back in 1976. They did this by taking soil from the Atacama Desert (Chile) and adding perchlorate before doing the test. They got the same result that Viking did but the scientists didn’t dismiss the results as Earth-based contaminants like they did 34 years ago.

DEC-15-2010 •Milky Way Not So Average• We understand a lot about our galaxy by looking at other galaxies. But recent findings show that either our galaxy has some unique attributes or all galaxies are stranger than we thought. The two Magellanic Clouds are more recent additions than we thought and the three-part system looks to be unique particularly in the luminosity of the clouds and in their proximity. The Large Magellanic Cloud has an intrinsic luminosity that is at the upper limit for irregular galaxies of that type. Also, in a survey of more than 25,000 Milky Way type spirals, only 3.5% have companions like the Magellanic Clouds.

DEC-14-2010 •Venus Miss• The Japanese spacecraft Akatsuki failed to enter into orbit around Venus. The rockets that were to fire for more than 9 minutes stopped after less than 3 minutes. Communication was briefly lost but was later reestablished. Since the fuel was not used up, JAXA will be able to try again - in 6 years.

DEC-10-2010 •Time Before Time• The discovery of the Cosmic Microwave Background put an end to the Steady State theory of the Universe and solidified the Big Bang Theory. The remnants of Steady State became the Quasi-Steady State theory - the idea that Big Bangs happen as part of a cycle. But recent research shoots down the cycle idea because there is no evidence that time itself existed before the Big Bang.

DEC-10-2010 •Peeling for Saturn• An emerging theory may explain how Saturn got its rings. If a large moon was slowly moving closer to Saturn it might drop off material as it did so. The first peelings would be of lighter material such as ice. Later peelings would consist of heavier material. This accounts for some rings that are mostly ice and others composed of darker material.


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