An astronomer at the University of Western Ontario has found a Soviet moon rover in recently released images from a NASA satellite.

Phil Stooke combed through data and images of the moon's surface from the Lunar Reconnaissance Orbiter that NASA released Monday.

Stooke compared the images to his own recently published reference book on moon geography, The International Atlas of Lunar Exploration, and pinpointed the location of the Soviet rover Lunokhod 2.

"The tracks were visible at once," said Stooke, in a statement.

The location of the rover was already known through laser ranging experiments, but there's no telescope on Earth or in Earth orbit powerful enough to actually see it.

"We knew within a few kilometres where it was. The laser beam spreads out a bit. It's not a pinpoint on the moon," Stooke said in an email.

The Lunar Reconnaissance Orbiter is taking pictures of the moon from its orbit about 50 kilometres above the surface. Its one-year mission is to produce a comprehensive moon map.

The Soviet Union landed Lunokhod 2 on the moon in January 1973, a month after the last American moonwalk. As the name suggests, it was the second of two solar-powered robotic rovers the Soviets sent to the moon.

Record-setting trip on lunar surface

The Lunokhod rovers were the first remote-controlled vehicles to travel on an extraterrestrial body and still hold the record for longest rover trip at 35 kilometres. (The Mars rovers Spirit and Opportunity have travelled 7.7 kilometres and 19.5 kilometres, respectively.)

Lunokhod 2's mission was to collect images from the moon, observe X-rays from the sun, study the moon's soil and measure its magnetic fields.

"The value here is partly the visual identification, but also the tracks, which will allow a detailed route map to be drawn for the first time," Stooke said.

"Knowing the history of the mission, it's possible to trace the rover's activities in fine detail. We can see where it measured the magnetic field, driving back and forth over the same route to improve the data," he said.

"And we can also see where it drove into a small crater, and accidentally covered its heat radiator with soil as it struggled to get out again. That ultimately caused it to overheat and stop working. And the rover itself shows up as a dark spot right where it stopped," said Stooke.

NASA released the first images from the Lunar Reconnaissance Orbiter in July 2009, revealing the landing sites of five of the six Apollo missions.