Curiosity (rover) conditions favorable for microbial life, including investigation of the role of water; and planetary habitability studies in preparation for human exploration. In December 2012, "Curiosity" two-year mission was extended indefinitely. On August 5, 2017, NASA celebrated the fifth anniversary of the "Curiosity" rover landing and related exploratory accomplishments on the planet Mars. The rover is still operational, and as of , "Curiosity" has been on Mars for sols ( total days) since landing on August 6, 2012. "(See current status.)" "Curiosity" design will serve as the basis for the planned Mars 2020 rover. As established by the Mars Exploration Program,
Mars Pathfinder Mars Pathfinder Mars Pathfinder (MESUR Pathfinder) is an American robotic spacecraft that landed a base station with a roving probe on Mars in 1997. It consisted of a lander, renamed the Carl Sagan Memorial Station, and a lightweight (10.6 kg/23 lb) wheeled robotic Mars rover named "Sojourner", which became the first rover to operate outside the Earth–Moon system. Launched on December 4, 1996 by NASA aboard a Delta II booster a month after the "Mars Global Surveyor" was launched, it landed on July 4, 1997 on Mars's Ares Vallis, in a region called Chryse Planitia in the Oxia Palus quadrangle.