The Last 31 Days in Astronomy

May 21, 2007•Strongest Evidence Yet for a Wet Mars•The strongest evidence so far that Mars was wetter in the past than it is now has been discovered by the Mars Rover Spirit. Stephen Squyres said “You could hear people gasp in astonishment ... the fact that we discovered something so new and so different after 1200 days on Mars ... makes you wonder what else is out there.” What is this evidence? A patch of dirt so rich in silica (90%) that water is probably the only it could have been produced. The area is called Gertrude Weise after one of the players in the All-American Girls Professional Baseball League. The discovery was aided by the fact that one of Spirit’s wheels is no longer rotating. The scuff marks created by the wheel expose otherwise unnoticed areas. http://www.jpl.nasa.gov/news/news.cfm?release=2007-061

May 29, 2007•New types of extrasolar planets•Astronomers have used ground-based telescopes including those at Lick to find extrasolar planets around type A stars- more specifically, old A type stars that are at the end of their hydrogen-burning phase. These brighter, larger stars are not usually studied for extrasolar planets because the variance in spectrographic measurements are more likely to be due to variability in the star rather than the wobble caused by planets. Nine A-type stars have been found with planets. Also, a transiting “hot Neptune” planet was found around Gliese 436. The result shows that the minimum mass, as determined when the planet was first discovered using the wobble method, is actually its actual mass. http://www.skyandtelescope.com/news/Retired_A_Star_Planets.html http://www.skyandtelescope.com/news/7751322.html

May 29, 2007•M81 looking better than ever•A new and stunning image of M81 has been released (see page 5). This Hubble image shows the spiral galaxy which is larger than the Milky Way. It is between 11 and 12 million light-years away. The black hole at the center of M81 is about 15 times larger than the one at the center of the Milky Way. http://www.skyandtelescope.com/news/7730677.html

June 1, 2007•Most massive star discovered•Astronomers from the University of Montreal have identified the most massive star ever weighed. This binary star weighs 114 times the mass of the Sun, with its companion star weighing 84 solar masses. http://www.space.com/scienceastronomy/070607_massive_star.html

June 5, 2007•Messenger sails past Venus•The Messenger spacecraft passed Venus on its way to Mercury. The first flyby of Mercury will be January of 2008 and it will enter into an orbit around Mercury in 2011. http://www.nasa.gov/mission_pages/messenger/timeline/index.html

June 5, 2007•Looking MACHO•A new method is being used to try to find dark matter. An object has been found that bends light coming from the Small Magellanic Cloud. The object bending or lensing the light would need to be about 10 solar masses and about 1600 light years away. But a star or binary star at the distance or location would be visible. Since it isn’t, it is thought to be a MAssive Compact Halo Object or MACHO.

June 7, 2007•Launch date set for Hubble repair•A launch date has been set for the Space Shuttle Atlantis to head toward the Hubble Space Telescope to make repairs and add capabilities. The launch date is Sept. 10, 2008. This will be the last Space Shuttle mission that has a destination other than the ISS. http://www.space.com/news/070607_hubble_launchdate.html

June 7, 2007•Most distant black hole found•The Canada-France-Hawaii Telescope (CHFT) using a new survey for distant quasers called the Canada-France High-z Quasar Survey (CFHQS) located a black hole 13 billion light-years from earth. This could provide information about the early evolution of the universe. http://www.space.com/scienceastronomy/070607_distant_blackhole.html

June 10, 2007 •Shuttle Launches and Docks•The Space Shuttle Atlantis took off from Cape Canaveral on June 8 and docked with the ISS on June 10. By the time you read this, the Shuttle should have landed. Upon her return, Sunita Williams will hold the record for the longest single duration in space by a woman. When this was mentioned at a post-launch press conference on June 8, shuttle program manager Wayne Hale said “records are made to be broken” and someday this record will be broken also. She already holds the record for most time spent in EVA by any woman. http://www.ndtv.com/convergence/ndtv/story.aspx?id=NEWEN20070014192 http://www.space.com/missionlaunches/070608_sts117_postlaunch.html