Lunokhod 2 (аппарат 8ЕЛ№204) was more advanced and the last of two unmanned lunar rovers landed on the Moon by the Soviet Union as part of the Lunokhod program. The launcher put the spacecraft into Earth parking orbit on January 8, 1973, followed by translunar injection. On January 12, 1973, Luna 21 was braked into a 90 by 100 km (approx. 56 by 62 mile) lunar orbit. The Luna 21 spacecraft landed on the Moon and deployed the second Soviet lunar rover, Lunokhod 2. The primary objectives of the mission were to collect images of the lunar surface, examine ambient light levels to determine the feasibility of astronomical observations from the Moon, perform laser ranging experiments from Earth, observe solar X-rays, measure local magnetic fields, and study mechanical properties of the lunar surface material. The landing occurred on January 15, 1973 at 23:35 UT in Le Monnier crater at 25.85 degrees N, 30.45 degrees E. After landing, the Lunokhod 2 took TV images of the surrounding area, then rolled down a ramp to the surface at 01:14 UT on 1973-01-16 and took pictures of the Luna 21 lander and landing site.
Lunokhod 2 was equipped with three slow-scan television cameras, one mounted high on the rover for navigation, which could return high resolution images at different rates—3.2, 5.7, 10.9 or 21.1 seconds per frame (not frames per second). These images were used by a five-man team of controllers on Earth who sent driving commands to the rover in real time. There were four panoramic cameras mounted on the rover. Power was supplied by a solar panel on the inside of a round hinged lid which covered the instrument bay, which would charge the batteries when opened. A polonium-210 radioactive heat source was used to keep the rover warm during the long lunar nights. Scientific instruments included a Soil Mechanics tester, Solar X-ray experiment, an Astrophotometer to measure visible and Ultraviolet light levels, a Magnetometer deployed in front of the rover on the end of a 2.5 m (8 ft 2 in) boom, a Radiometer, a Photodetector (Rubin-1) for laser detection experiments, and a French-supplied laser Corner Reflector.p to the surface at 01:14 UT on 1973-01-16 and took pictures of the Luna 21 lander and landing site. Results Lunokhod 2 operated for about 4 months, covered 37 km (23 mi) of terrain, including hilly upland areas and rilles, and sent back 86 panoramic images and over 80,000 TV pictures. The 37 km journey remains the longest any robotic rover has ever been driven on another celestial body. Many mechanical tests of the surface, laser ranging measurements, and other experiments were completed during this time.