Water on Mars any point in the year but would be ideal for solid carbon dioxide. The carbon dioxide melting in the warmer summer would yield liquid carbon dioxide which would then form the gullies. Even if gullies are carved by flowing water at the surface, the exact source of the water and the mechanisms behind its motion are not understood. The dry gullies are deep grooves etched into the slopes that are there year-round. There are many other features on Mars, and some of them change seasonally. In August 2011, NASA announced the discovery by undergraduate student Lujendra Ojha of current seasonal
Life on Mars readings. Even if the mission is to determine that microscopic Martian life is the seasonal source of the methane, the life forms probably reside far below the surface, outside of the rover's reach. The first measurements with the Tunable Laser Spectrometer (TLS) in the "Curiosity" rover indicated that there is less than 5 ppb of methane at the landing site at the point of the measurement. On July 19, 2013, NASA scientists published the results of a new analysis of the atmosphere of Mars, reporting a lack of methane around the landing site of the "Curiosity" rover. On September 19,