Lunokhod programme

Lunokhod (Russian: Луноход, IPA: [lʊnɐˈxot], "Moonwalker") was a series of Soviet robotic lunar rovers designed to land on the Moon between 1969 and 1977.

[citation needed] The Lunokhod rovers were lunar vehicles formed of a tub-like compartment with a large convex lid on eight independently-powered wheels.

The power was supplied during the lunar day by a GaAs solar array on the inside of a round hinged lid which covered the instrument bay, which would charge the batteries when opened.

[9] To be able to work in a vacuum a special fluoride-based lubricant was used for the rover's mechanical parts, and the electric motors, one in each wheel hub, were enclosed in pressurised containers.

After reaching Earth parking orbit, the final stage of Luna 17's launching rocket fired to place it into a trajectory towards the Moon (November 10, 1970 at 14:54 UTC).

[14] An urban legend was spread among the Soviet Union that the Lunokhod rover was driven by a “KGB Dwarf”,[15] however it was never explained how supplies were stored to keep them alive for an 11-month mission.

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.

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.

Lunokhod 2 operated for about four months, covered 42 km (26 miles) of terrain,[20] including driving into hilly upland areas and rilles.

In 2010, nearly forty years after the 1971 loss of signal from Lunokhod 1, the NASA Lunar Reconnaissance Orbiter photographed its tracks and final location, and researchers, using a telescopic pulsed-laser rangefinder, detected the robot's retroreflector.

For comparison, the similarly sized NASA Mars Exploration Rovers, Spirit and Opportunity had, by their fifth anniversary in January 2009, traveled a total of 21 km (13 miles) and transmitted over 125,000 images.

[22] According to a French documentary television film Tank on the Moon by Jean Afanassieff, the Lunokhod design returned to the limelight 15 years later due to the Chernobyl nuclear power plant disaster on April 26, 1986.

[23] The East German-built remote controlled bulldozers available to Soviet civil defense troops weighed dozens of tons – too heavy to operate on the remaining parts of the partially collapsed reactor building roof.

Human labourers could not be employed to shovel debris since work shifts were limited to 90-second intervals due to intense ionizing radiation.

[24] Lunokhod designers were called back from retirement, and in two weeks rovers were made which used nuclear decay heat sources for internal rack climate control, their electronic systems were already hardened to partly resist radiation.

[23] This benefit allowed the 1986 designers to quickly devise a derived vehicle type for nuclear disaster recovery work.

On July 15, two rovers, called STR-1,[12] were delivered to the Chernobyl accident zone and proved useful for clearing debris, earning awards for the designers.

Due to extremely high radiation levels, both STR-1 rovers eventually failed, and human workers (later named liquidators) were called in once again.