Lunokhod programme

• 1. Introduction

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  The Lunokhod programme's first machine never reached the Moon. On the 19th of February 1969, the rocket carrying it disintegrated within seconds of launch. Its radioactive polonium-210 heat source scattered across a stretch of Russia, and the rest of the world would not learn what had been lost for years.

  Lunokhod, a name that means "Moonwalker," was the Soviet Union's series of robotic lunar rovers, built to land on the Moon between 1969 and 1977. What began as a backup plan for a human Moon landing turned into something else entirely. The rovers became unmanned machines roaming another world, sending back images while Soviet cosmonauts never got the chance to follow them.

  How did a rover meant to babysit astronauts become the mission itself? And what happened when the design resurfaced decades later, at a ruined power station and inside a New York auction house?

• 2. A Plan B For Cosmonauts

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  In mid-1968, at a classified facility near Simferopol in Crimea, Soviet engineers built a lunodrom, a Moondrome for testing rover chassis. The site covered one hectare, about 120 by 70 meters, shaped to mimic the Moon's terrain. Builders moved more than 3,000 cubic meters of soil to shape the ground. It held 54 craters, some as wide as 16 meters, and around 160 scattered rocks of varying sizes. Gray and black bricks ringed the entire area. There, engineers tested how the Lunokhod chassis handled obstacles, and how well a cosmonaut could learn to drive one by remote control.

  Simferopol-28, the closed town holding this training ground, held more antennas, more land area, and more staff than any other Soviet tracking site. It formed one node in a network of ten stations tracking Earth satellites and running command and control for Soviet space efforts, civil and military. Working alongside the Evpatoria Deep Space Tracking Facility, it supported every lunar programme the Soviet Union ran.

  At least four complete Lunokhod vehicles came off the line, numbered 201, 203, 204 and 205. Weeks before any cosmonaut landed, the plan sent an uncrewed LK-R lander and two Lunokhod rovers ahead of him. They would scout the ground around the LK-R and LK sites, work as radio beacons for precision landings, and give a visual check on conditions. Vehicle 205 would carry a different fate entirely, one that never left the ground.

• 3. Built For The Vacuum

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  Each Lunokhod rover took the shape of a tub-like compartment sealed under a large convex lid, riding on eight independently powered wheels. A cone-shaped antenna and a highly directional helical antenna handled communication. Television cameras rode alongside extendable devices that pressed into the lunar soil, measuring its density and mechanical properties. A separate scientific payload varied from one mission to the next.

  Georgy Babakin led the Lunokhod design work at the Lavochkin design bureau, while Alexander Kemurdzhian designed the metal chassis itself. Batteries powered the rover, which ran only during the lunar day and paused occasionally to recharge. A GaAs solar array lined the inside of the rover's round hinged lid, and opening that lid each day let sunlight refill the batteries. When lunar night fell, the lid closed and a radioisotope heater unit kept the electronics warm enough to survive the cold.

  To operate in the vacuum of space, engineers coated the rover's mechanical parts in a special fluoride-based lubricant. Each wheel hub held its own electric motor, sealed inside a pressurised container to keep it working.

  Standing 135 cm high with a mass of 840 kg, the rover measured about 170 cm long and 160 cm wide. Eight wheels, each with its own suspension, motor and brake, gave it two possible speeds, roughly 1 and 2 km/h. Luna spacecraft carried each Lunokhod to the surface, launched from Earth atop Proton-K rockets. The lander section built for these missions closely matched the one used on separate Soviet sample-return flights.

  None of this engineering mattered yet. The first finished vehicle still had to survive its own rocket.

• 4. Two Rockets, One Rover

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  Vehicle 8ЕЛ№203 replaced the rover lost weeks earlier. Renamed Lunokhod 1, it became the first of two rovers the Soviet Union would land on the Moon, riding inside a spacecraft called Luna 17.

  Luna 17 launched on the 10th of November 1970, at 14:44:01 UTC. At 14:54 UTC that same day, the rocket's final stage fired again, bending the craft's path toward the Moon. Two course correction manoeuvres followed, on the 12th and the 14th of November. Luna 17 then entered lunar orbit on the 15th of November 1970, at 22:00 UTC.

  It soft-landed in the Sea of Rains on the 17th of November 1970, at 03:47 UTC. The lander unfolded dual ramps, and at 06:28 UT the rover rolled down them onto the lunar surface.

  Lunokhod 1 carried two television cameras and four panoramic telephotometers for imaging. Its instruments included a RIFMA X-ray fluorescence spectrometer, an RT-1 X-ray telescope, a PrOP odometer-penetrometer, an RV-2N radiation detector, and a TL laser retroreflector.

  An urban legend spread through the Soviet Union claiming a "KGB Dwarf" sat inside driving the rover. No one ever explained how enough supplies could have been hidden aboard to keep a driver alive for an 11-month mission.

  Three years later, a second, more advanced rover would follow it toward the Moon.

• 5. The Second Rover Goes Further

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  On the 8th of January 1973, the rocket carrying vehicle 8ЕЛ№204 reached Earth parking orbit before a translunar injection burn sent it toward the Moon. On the 12th of January, Luna 21 braked into a lunar orbit measuring 90 by 100 km.

  The Luna 21 spacecraft then landed to deploy Lunokhod 2. Its mission carried six goals. It would image the lunar surface, gauge ambient light for possible astronomy, and run laser-ranging tests from Earth. It would also watch solar X-rays, measure local magnetic fields, and study the ground's mechanical properties.

  The landing came on the 15th of January 1973, at 23:35 UT, inside Le Monnier crater, at 25.85 degrees north and 30.45 degrees east. After taking television images of the surrounding area, Lunokhod 2 rolled down a ramp onto the surface at 01:14 UT on the 16th of January. It then photographed the Luna 21 lander and the landing site itself.

  Three slow-scan television cameras rode on the rover, one mounted high for navigation, capable of images at 3.2, 5.7, 10.9 or 21.1 seconds per frame. A five-man team of controllers on Earth used these images to send driving commands in real time. Four more panoramic cameras rounded out the rover's imaging suite.

  Lunokhod 2's scientific instruments included a soil mechanics tester, a solar X-ray experiment, and an astrophotometer measuring visible and ultraviolet light. A magnetometer sat on a 2.5-meter boom extended in front of the rover. Alongside it rode a radiometer, a laser-detecting photodetector called Rubin-1, and a laser corner reflector supplied by France.

  A third rover, vehicle 205, was already being built for a follow-up landing.

• 6. How Far They Went

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  Vehicle 8ЕЛ№205, later called Lunokhod 3, targeted a landing as Luna 25 in 1977. It never left the ground, grounded by a shortage of launchers and funding. It remains today at the NPO Lavochkin museum.

  Across 322 Earth days of operation, Lunokhod 1 travelled 10.5 km and sent back more than 20,000 television images plus 206 high-resolution panoramas. It also ran twenty-five soil analyses with its RIFMA spectrometer and used its penetrometer at 500 separate spots.

  Lunokhod 2 worked for about four months and covered 42 km of terrain, driving through hilly upland areas and rilles. That distance held the record for the longest surface travel by any extraterrestrial vehicle until 2014. It sent back 86 panoramic images and more than 80,000 television pictures, alongside mechanical tests and laser-ranging measurements.

  Not until 1997, when Mars Pathfinder deployed its "Sojourner" rover, did another remote-controlled vehicle reach an extraterrestrial body. By comparison, NASA's similarly sized Mars Exploration Rovers, Spirit and Opportunity, had traveled a combined 21 km by their fifth anniversary in January 2009. Together they had sent back more than 125,000 images.

  None of these totals hinted at the role Lunokhod's design would later play, far from the Moon, in the wake of a nuclear disaster.

• 7. A Second Life At Chernobyl

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  A French documentary film, Tank on the Moon, made by Jean Afanassieff, traced how the Lunokhod design returned to attention fifteen years later. The trigger was the Chernobyl nuclear disaster, on the 26th of April 1986.

  East German-built remote-controlled bulldozers, weighing dozens of tons, sat ready in the hands of Soviet civil defense troops. They proved far too heavy for the collapsed reactor building's remaining roof. Human labourers could not shovel the debris either. Radiation was so intense that work shifts there were limited to 90-second intervals.

  Lunokhod's original designers were called back from retirement. In two weeks, they built new rovers using nuclear decay heat sources for internal climate control, their electronics already hardened against radiation. This let the 1986 team quickly adapt the old design into a new vehicle built for nuclear disaster recovery.

  On the 15th of July, two of these rovers, called STR-1, arrived at the Chernobyl accident zone and proved useful clearing debris, earning designers awards. Extreme radiation eventually broke down both STR-1 rovers, and human workers, later known as liquidators, had to finish the job.

  Decades after Chernobyl, the original Lunokhod rovers themselves became the subject of a very different kind of recovery effort, this time on the Moon itself.

• 8. Finding And Owning Lunokhod

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  Until 2010, Lunokhod 1's exact resting place stayed uncertain by a few kilometers. Lunar laser ranging experiments had failed to detect any return signal from its retroreflector since the 1970s.

  On the 17th of March 2010, Albert Abdrakhimov spotted both the lander and the rover in a Lunar Reconnaissance Orbiter image, catalogued M114185541RC. On the 22nd of April, Tom Murphy of UCSD and Russet McMillan, at the Apache Point Observatory, detected the robot's retroreflector using a pulsed-laser rangefinder.

  Lunokhod 2, unlike its sibling, has never gone quiet. Laser ranging experiments still track it today, with its position known to sub-metre accuracy.

  In December 1993, the Lavochkin Association sold ownership of Lunokhod 2 and the Luna 21 lander at a Sotheby's auction in New York. The auction catalogue misidentified the lot, listing it as Luna 17 and Lunokhod 1 instead. The buyer was Richard Garriott, a computer gaming entrepreneur and astronaut's son also known by his game character's name, Lord British.

  In a 2001 interview, Garriott said: "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, I am not a government. Summarily, I claim the Moon in the name of Lord British!" By 2007, Garriott said, he still owned Lunokhod 2.

  Every time an astronomer bounces a laser off Lunokhod 2's reflector, Garriott's decades-old claim to a piece of the Moon gets measured all over again.