Mars in fiction the past; Mars is a setting rather than a goal. Mariner 4 in July 1965 found that Mars—contrary to expectations—is heavily cratered, with a very thin atmosphere. No canals were found; while scientists did not believe that Mars was a moist planet, the lack of surface water surprised them. Science fiction had so influenced real explorations of the planet, however—Carl Sagan was among the many fans who became scientists—that after Mariner 9 in 1971-1972, craters were named after Wells, Burroughs, and other authors. The Mariner and Viking space probes confirmed that the Martian environment is extremely hostile to life. By
Space probe on another planet (Venus) and to transmit data from there back to Earth. Upon its arrival at Mars on November 13, 1971, Mariner 9 became the first space probe to maintain orbit around another planet. First soft landing on Mars (December 2, 1971) The lander began transmitting to the Mars 3 orbiter 90 seconds after landing. After 20 seconds, transmission stopped for unknown reasons. First successful rover on Mars. The Mars Exploration Rovers, "Spirit" and "Opportunity" landed on Mars to explore the Martian surface and geology, and searched for clues to past water activity on Mars. They were each launched