NASA Lunar Orbiter Spots Old Soviet Moon Landers
Luna 16 moon lander.
Credit: National Space Science Data Center

NASA's sharp-eyed Lunar Reconnaissance Orbiter (LRO) has been used to locate vintage space hardware lobbed to the moon in the 1970s by the former Soviet Union.

LRO has been a "boon for the moon," said Mark Robinson of Arizona State University in Tempe, Ariz., the principal investigator for the high-powered Lunar Reconnaissance Orbiter Camera, or LROC for short.

In a set of just-released LROC images, the former Soviet Union's Luna 20 and Luna 24 have been sighted. The Soviet Union successfully executed three robotic sample return missions as part of the Cold War competition with the United States, Robinson said.

Some Soviet lunar rovers, called Lunokhods, were also spotted by the eagle camera eyes of LRO.

Soviet-style moon probes

The first mission, Luna 16, returned to Earth a small sample of 0.22 pounds (101 grams) from the moon's Mare Fecunditatis in September of 1970, a period of time between NASA's Apollo 12 and Apollo 14 human landings.

In February 1972, Luna 20 returned a smaller sample — 55 grams — of soil from the Apollonius highlands region.

Luna 16 and 20 were very similar in design and sampling method, Robinson said. A drill at the end of the sampling arm collected soil from a few tens of centimeters below the surface. The arm then placed the sample into the return capsule on top of the vehicle that was rocketed off the moon for a parachute landing on Earth.

The Luna 20 sample contained minerals similar to those sampled by the Apollo 16 astronauts two months later from the moon's Cayley plains.

In one LROC image, the distinctive shadow at the Luna 20 site is most likely that of the outstretched robotic sampling arm.

Try and try again

In October of 1974 Luna 23 set down on Mare Crisium, however technical difficulties prevented it from successfully acquiring a sample and launching lunar specimens back to Earth.

In try and try again mode, the Soviets were successful in landing Luna 24 on the moon in August of 1976.

Luna 24 was designed to penetrate over 6 feet (2 meters) into the lunar soil. It collected a better section and a larger sample — some 170 grams — that was launched back to Earth.

The relative positions of the Luna 23 and Luna 24 landers were not well known, Robinson said. But from LRO's narrow angle camera images the distance between the two spacecraft appears to be roughly 8,000 feet (2,400 meters).

In the Luna 24 imagery, a viewer can observe a few very bright pixels near the lander, perhaps small pieces of material blown off the descent stage as the ascent stage blasted off towards Earth, Robinson said.

Lunokhods rovers found

In another release of LROC imagery, the Soviet Union's Lunokhod 1 and Lunokhod 2 moon rovers have been found.

Each of the 8-wheeled lunar buggies was delivered by a lander. After their respective touch downs — in November 1970 and in January 1973 — the rovers rolled down ramps onto the moon's terrain.

The rovers were driven by solar power during the day; at night they would park and rely on thermal energy from a polonium-210 radioisotope heater to survive the lunar cold.

One of the happiest on Earth to hear of finding the Lunokhods was private space traveler, Richard Garriott, who flew a self-financed trek to the International Space Station in 2008.

Turns out that entrepreneur Garriott had bought both the Luna 21 lander and the Lunokhod 2 rover from Russia's Lovochkin Association for $68,500 in 1993, during a Sotheby's space auction in New York.