at altitude, and the craft began to de-orbit. At an altitude of the main thrusters began firing, slowing the fall until a height of was reached. At this point the main thrusters shut down and the secondary thrusters ignited, slowing the fall until the lander was above the surface, where the engine was switched off. Landing occurred 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 January 16 and took pictures of the Luna 21 lander and landing site, driving for 30 metres. After a period of charging up its batteries, it took more pictures of the site and the lander, and then set off to explore the moon. The rover would run during the lunar day, stopping occasionally to recharge its batteries with the solar panels. At night the rover hibernated until the next sunrise, heated by the radioactive source. January 18, 1973 to January 24, 1973: The rover drives 1,260 metres February 8 to 23: The rover drives 9,086 metres further March 11 to 23: The rover drives 16,533 metres further April 9 to 22: The rover drives 8,600 metres further May 8 to June 3: The rover drives 880 metres further End of mission On June 4, 1973 it was announced that the program was completed, leading to speculation that the vehicle probably failed in mid-May or could not be revived after the lunar night of May–June. More recently, Alexander Basilevsky related an account in which on May 9, the rover's open lid touched a crater wall and became covered with dust. When the lid was closed, this dust (a very good insulator) was dumped on to the radiators. The following day, May 10, controllers saw the internal temperature of Lunokhod 2 climb as it was unable to cool itself, eventually rendering the rover inoperable. On May 11, signal from the rover was lost. Results Lunokhod 2 operated for about four months, and the original estimate was that it covered of terrain, including hilly upland areas and rilles, and sent back 86 panoramic images and over 80,000 TV pictures. Many mechanical tests of the surface, laser ranging measurements, and other experiments were completed during this time. Lunokhod 2 was thought to have covered based on wheel rotations but