and transmitted over 125,000 images. Chernobyl legacy 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. 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. 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. 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, 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. Locations and ownership Until 2010, the final location of Lunokhod 1 was uncertain by a few kilometers. Lunar laser ranging experiments had failed to detect a return signal from its retroreflector since the 1970s. On March 17, 2010, Albert Abdrakhimov found both the lander and the rover in Lunar Reconnaissance Orbiter image M114185541RC. On April 22, Tom Murphy (UCSD) and Russet McMillan at the Apache Point Observatory detected the robot's retroreflector using the Apache Point telescopic pulsed-laser rangefinder. Lunokhod 2 continues to be detected by lunar laser ranging experiments and its position is known to sub-metre accuracy. Ownership of Lunokhod 2 and the Luna 21 lander was sold by the Lavochkin Association for in December 1993 at a Sotheby's auction in New York (although the catalogue incorrectly lists lot 68A as Luna 17/Lunokhod 1). The buyer was computer gaming entrepreneur and astronaut's son Richard Garriott, who is also known by the name of his gaming character Lord British. Garriott stated in a 2001 interview: "I purchased Lunakod 21 from the Russians. I am now the world's only private owner of an object on a foreign celestial body. Though there are international treaties that say no government shall lay claim to geography off planet earth,