The Last 31 Days in Astronomy

SEP-26-2007 • Opportunity ready for Victoria Crater science • The Mars rover Opportunity has reached its first science location inside of Victoria Crater. The rover is at an angle of 25 degrees which requires some safety testing before attempting to use some of the scientific apparatus on board. http://www.jpl.nasa.gov/news/news.cfm?release=2007-109

SEP-27-2007 • DAWN rises • The Dawn spacecraft finally is on its way to study Vesta and Ceres. The spacecraft will use ion propulsion and become the first spacecraft to orbit two different solar system objects (not counting the Earth and the Sun). A test of the ion engine on Oct. 9 was successful. http://www.jpl.nasa.gov/news/news.cfm?release=2007-110

OCT-01-2007 • NASA Detects Arctic Sea Ice Reduction • A NASA-led study has found that the arctic year-rough ice cover has sustained a 23% loss over the last two years. This represents an area the size of Texas and California combined. http://www.jpl.nasa.gov/news/news.cfm?release=2007-112

OCT-04-2007 • M42 Older and Closer • Radio astronomical measurements taken by the VLBA facility shows that M42 is both closer and older than was previously thought. The measurements used parallax by comparing the location of the Orion Nebula when viewed from opposite points of the Earth’s orbit around the sun. The background “stars” used in this measurement were actually a couple of pulsars. The new distance to M42 is 1270 light years and the age of the stars that can be seen in the nebula are 2 million years. The previously best measurements had the nebula 1565 light years away and the stars appeared to be one million years old. http://www.nrao.edu/pr/2007/oriondistance/

OCT-08-2007 • Mercury Images • Astronomers at the University of North Carolina have imaged Mercury using a technique called lucky imaging. In this technique, many images are taken and only the sharpest are kept to produce the result. The 4 meter SOAR telescope at Cerro Pechon in Chile was stopped down so that it became a 1.35 meter, f/38 telescope. They then recorded up to 140 frames per second. A computer picks the sharpest images. The resulting images of Mercury show unprecedented detail. http://www.skyandtelescope.com/news/10317557.html

OCT-10-2007 • New Crew at the ISS • A new crew is on the way to the International Space Station. The Soyuz arrived at the ISS on the 12th. On the 19th, Expedition Crew 16 officially takes over and Peggy Whitson will be the first woman commander on the ISS. When the next Shuttle arrives at the ISS, it will be the first time that both shuttle and ISS crews are commanded by women. http://www.space.com/news/cs-071012-expedition16-personal.html

OCT-11-2007 • ATA-42 Starts • The Allen Telescope Array at Hat Creek, California celebrated its inauguration. The array of 42 telescopes were put through their paces after Paul Allen pushed the button set up for this occasion. http://www.nytimes.com/2007/10/11/science/11seti.html

OCT-11-2007 • Weird CO2 found • Astronomers were stuck. European astronomers looking at data from the Venus Express thought they had discovered some previously unknown organic molecule. Meanwhile scientists at NASA-Goddard thought they saw methane on Mars which shouldn’t be because methane breaks down under Martian conditions. Turns out that both groups were confused by a strange form of CO2 that includes a rare isotope of oxygen. The discovery is interesting because this new CO2 molecule can absorb some wavelengths that normal CO2 cannot and thus it adds a small but important part of the runaway greenhouse effect on Venus. On Mars, it accounts for how there can be so much apparent methane on a relatively warm planet that does not get methane replenished by bovine flatulence. http://www.skyandtelescope.com/news/10452322.html