1st Mars landing achieved 7 yrs post 1st manned moon landing

The first-ever successful unmanned Mars landing was achieved exactly seven years after the first manned spacecraft landed on the moon on July 20, 1969. On July 20, 1976, NASA's Viking 1 lander separated from its orbiter and touched down on the Martian surface. It was US' first attempt at Mars landing, which followed several failed attempts by the Soviet Union.