Viking 1 and Viking 2 are the spacecrafts that landed on the surface of Mars in 1970s, 1976 to be precise. Both were part of the Viking mission and consisted of a lander and an orbiter each. The lander landed on the planet's surface, while the orbiter collected information from the orbit. Viking 1 provided data for six years after landing and Viking 2 survived for three years.
The missions to attempt landing were the Mars mission probes: Mars 2, Mars 3 and Mars 6. They either failed during descent or immediately after landing.
The Viking mission was the only successful Mars mission of the decade of 1970. The surface maps generated by the Viking orbiters are still in use.
Several other attempts at landing have been made since then, including some successful ones.
The name of the spacecrafts that landed on Mars in 1976 were Viking 1 and its sister ship, Viking 2. Viking 1 landed on Mars July 20, 1976. Both were sent off into space on September 9, 1975. They originally sent these to a place that looked like a deep river bed, in hopes of being able to find water, which is a sign that life may be sustainable.
The Viking landers were the first spacecraft that landed on mars in 1970. viking 1 and viking 2 each had both orbiter and lander.
Viking 1 lander got separated from the Orbiter and touched the surface of Mars on july20, 1976.
Viking 2 touched mars after 2 months i.e. on september 3, 1976.