Luna 21

"Lunik 21"
NSSDC ID: 73-001A

Description:
The Luna 21 mission deployed the second Soviet lunar rover
(Lunokhod 2). The SL-12/D-1-e launcher put the spacecraft into
Earth parking orbit followed by translunar injection. On 12 January
1973, Luna 12 was braked into a 90 X 100 km orbit about the
Moon. On 13 and 14 January, the perilune was lowered to 16 km
altitude. On 15 January after 40 orbits, the braking rocket was
fired at 16 km altitude, and the craft went into free fall. At an 
altitude of 750 meters the main thrusters began firing, slowing
the fall until a height of 22 meters was reached. At this point the
main thrusters shut down and the secondary thrusters ignited,
slowing the fall until the lander was 1.5 meters above the surface,
where the engine was cut off. Landing occurred at 23:35 UT. The
lander carried a bas relief of Lenin and the Soviet coat-of-arms.
The lander and rover together weighed 1814 kg. 

The Lunokhod 2 rover was equipped with two TV cameras, one
mounted high on the rover for navigation and one lower. Total
mass of the rover was 840 kg. It carried a solar panel for battery
charging, soil mechanics tester, solar X-ray experiment, astro-
photometer, magnetometer, radiometer, and a French-supplied
laser corner-reflector. The rover was controlled from Earth by a
five-man team using images updated every 3 seconds.