Luna 21's mission was to deliver a Soviet lunar rover (called Lunokhod 2) to the Moon. There, the rover would collect images of the lunar surface, determine whether ambient light levels are conducive to using the Moon as a base for astronomical observations, perform laser ranging experiments from Earth, observe solar X-rays, measure local magnetic fields, and study mechanical properties of the lunar soil.
Luna 21 successfully delivered the Lunokhod 2 rover to the surface of the Moon.
Jan. 8, 1973 | 06:55:38: Launch
Jan. 12, 1973: Lunar Orbit Insertion
Jan. 15, 1973 | 22:35 UT: Lunar Landing
Jan. 16, 1973 | 01:14 UT: Rover Deployment
Luna 21 carried the second successful Soviet "8YeL" lunar rover, Lunokhod 2, and was launched less than a month after the last Apollo lunar landing.
After a midcourse correction the day after launch, Luna 21 entered orbit around the Moon on Jan. 12, 1973. Orbital parameters were 62 x 56 miles (100 x 90 kilometers) at 60 degrees inclination. On Jan. 15, the spacecraft deorbited and, after multiple engine firings, landed on the Moon at 22:35 UT the same day, inside the LeMonnier crater at 25 degrees 51 minutes north latitude and 30 degrees 27 minutes east longitude, between Mare Serenitatis and the Taurus Mountains. Less than 3 hours later, at 01:14 UT on Jan. 16, the rover disembarked from Luna 21 onto the lunar surface.
Launch Vehicle: Proton booster plus upper stage and escape stages; 8K82K + Blok D (Proton-K no. 259-01)
Spacecraft Mass: 13,117 pounds (5,950 kilograms)
Spacecraft Instruments (on Lunokhod 2 rover):
Imaging system (three low-resolution TVs and four high-resolution photometers
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