title: Exploration of Mars
context: The first to contact the surface were two Soviet probes: Mars 2 lander on November 27 and Mars 3 lander on December 2, 1971—Mars 2 failed during descent and Mars 3 about twenty seconds after the first Martian soft landing.[16] Mars 6 failed during descent but did return some corrupted atmospheric data in 1974. [17] The 1975 NASA launches of the Viking program consisted of two orbiters, each with a lander that successfully soft landed in 1976. Viking 1 remained operational for six years, Viking 2 for three. The Viking landers relayed the first color panoramas of Mars.[18]
question: What was the first spacecraft to land on Mars?
answers: Viking 1