Viking 2 Lander
The Viking mission consisted of launches of two separate spacecraft to Mars, Viking 1, launched
on 20 August 1975,
and Viking 2, launched on 9 September 1975. Each spacecraft consisted of an orbiter and a
lander. After orbiting Mars and returning images used for landing site selection, the
orbiter and lander detached and the lander entered the martian atmosphere and soft-landed
at the selected site. The orbiters continued imaging,
experiments and other scientific
operations from orbit while the landers deployed instruments on the surface. The fully
fueled orbiter-lander pair had a mass of 3530 kg. After separation and landing, the lander
had a mass of about 600 kg and the orbiter 900 kg. The lander was encased in a bioshield
at launch to prevent contamination by terrestrial organisms.