The Mars Global Surveyor (MGS) is a NASA mission that arrived at Mars in September, 1997, and for nine years circled the planet every two hours in a polar orbit (that is, traveling from the north pole to the south pole and back) at an altitude of 400 kilometers (249 miles) above the Martian surface. MGS went silent in November, 2006. It carried a suite of five instruments designed to study the entire Martian surface, atmosphere, and interior, and their datasets have provided astronomers with a wealth of information about the climate and atmosphere of Mars. The results are not only interesting to students of Mars. As astronomers discover new extrasolar planets, and as Earth-based meteorologists test the realism of their atmospheric models, the results of meteorological analyses of another planet besides Earth provide an important reference.
March 17th, 2010