Mars has lost at least half its atmosphere since the planet’s inception, Curiosity confirms. Mars’ atmosphere is 100 times thinner than Earth’s. Other than shielding life from harmful UV radiation, atmosphere also controls the fluctuations in climate. Because Mars’ atmosphere contains more heavier varieties of carbon dioxide than lighter ones, the ratio suggest the planet has sadly lost much of its atmosphere. Mars’ thin atmosphere has nearly untraceable amounts of methane, only a few parts of methane per billion parts of Martian atmosphere. Microbes like bacteria emit methane. In fact, 95% of methane on Earth is produced by biological processes. Though Curiosity failed to find traces of methane in Gale Crater, Mars may yet host methane elsewhere.
Curiosity used its SAM instruments (Sample Analysis at Mars) and TLS (Tunable Laser Spectrometer). In the near future, SAM will analyze its first solid sample to search for organic compounds in rocks.
In addition, air samples from Curiosity match ones from trapped air bubbles in meteorites found on Earth. Ergo, those meteorites definitely originated from Mars. 1 billion years ago, a large asteroid collided into Mars and split into fragments.
“NASA Rover Finds Clues to Changes in Mars’ Atmosphere.” JPL Caltech. JPL, 2 Nov 2012. Web. 5 Nov 2012. <http://mars.jpl.nasa.gov/msl/news/whatsnew/index.cfm?FuseAction=ShowNews&NewsID=1388>.
Vergano, Dan. “NASA’s Curiosity rover confirms Mars lost atmosphere.” USA Today. USA Today, 2 Nov 2012. Web. 5 Nov 2012. <http://www.usatoday.com/story/tech/sciencefair/2012/11/02/curiosity-rover-mars-methane/1678033/>.