Carried aboard the Soviet lunar lander Luna 21, the Lunokhod 2 rover was to be the second Soviet lunar rover on 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.
Though Lunokhod 2 operated for only four months before it drove into a crater and brought the mission to a premature end, it accomplished a great deal. It covered 23 miles (37 kilometers) of terrain, including hilly upland areas and rilles, transmitted 86 panoramic images and more than 80,000 TV pictures of the lunar surface, and conducted at least 740 mechanical tests of the soil. During the laser ranging experiment, the Earth-Moon distance was measured to within 8 to 12 inches (20 to 30 centimeters). Surprisingly, the lunar night sky was found to be 13 to 15 times brighter than the Earth night sky, casting doubt upon the Moon's suitability for observatories in visible and ultraviolet light (at least on the Earth-facing side)
Jan. 8, 1973 | 06:55:38: Launch (Luna 21)
Jan. 15, 1973 | 22:35 UT: Lunar Landing
Jan. 16, 1973 | 01:14 UT: Rover Deployment
May 9, 1973: End of Mission
Just three hours after being safely delivered to the Moon onboard the Luna 21 lander late on Jan. 15, 1973, the Soviet Lunokhod 2 rover disembarked onto the lunar surface at 01:14 UT on Jan. 16.
The 1,852-pound (840-kilogram) Lunokhod 2 was an improved version of its predecessor and was equipped with a third TV camera, an improved eight-wheel traction system, and additional scientific instrumentation. By the end of its first lunar day (about one Earth month), Lunokhod 2 had already traveled farther than Lunokhod 1 in its entire operational life.
On May 9, the rover inadvertently rolled into a crater and dust covered its solar panels, disrupting temperatures in the vehicle. Attempts to save the rover failed, and on June 3 the Soviet news agency announced that its mission was over.
Before last contact, the rover took 80,000 TV pictures and 86 panoramic photos and had performed hundreds of mechanical and chemical surveys of the soil. The Soviets later revealed that during a conference on planetary exploration in Moscow, Jan. 29 to Feb. 2, 1973 (that is, after Luna 21 had landed on the Moon), an American scientist had given photos of the lunar surface around the Luna 21 landing site to a Soviet engineer in charge of the Lunokhod 2 mission. These photos, taken prior to the Apollo 17 landing, were later used by the "driver team" to navigate the new rover on its mission on the Moon.
Launch Vehicle: Proton booster plus upper stage and escape stages; 8K82K + Blok D (Proton-K no. 259-01)
Spacecraft Mass: 1,852 pounds (840 kilograms)
Imaging system (three low-resolution TVs and four high-resolution photometers
- Credit: NASA