On November 29, 2018, in a Sotheby’s auction room in New York, bidders competed over an object smaller than a fingernail clipping. Inside a small metal block, under a magnifying lens, sat three tiny specks of gray rock.
When the hammer fell, they sold for $855,000. They had come from the Moon, carried home not by astronauts, but by a robot.
The robot that went to fetch the Moon
By 1970, American astronauts had already brought back hundreds of pounds of lunar rock on Apollo 11 and Apollo 12. The Soviet Union, having lost the race to land people on the Moon, took a different approach. It would send machines.
On September 20, 1970, the Soviet probe Luna 16 touched down in the Sea of Fertility, a dark lava plain on the Moon’s near side. Within hours, an automatic drill bored about 35 centimeters into the lunar soil and deposited the sample into a sealed capsule on top of the lander.
The next day, the upper stage blasted off from the Moon and headed for home. On September 24, the capsule parachuted down in Kazakhstan. Luna 16 had become the first robotic spacecraft to return a sample from another world.
A small but precious haul
The capsule held about 101 grams of lunar soil and rock, roughly the weight of a small apple. That was tiny compared with the Apollo hauls, but it proved robots could do the job.
Two more Soviet probes, Luna 20 in 1972 and Luna 24 in 1976, returned more samples. Together, the three missions brought back about 0.3 kilograms of lunar material.
A gift to a secret hero
Most of the Luna samples stayed in Soviet labs, and some were traded or given to other countries. But a few grains took a more personal path.
The Soviet government gave a small display of Luna 16 material to Nina Ivanovna Koroleva, the widow of Sergei Korolev. Korolev was the “Chief Designer” behind Sputnik and Yuri Gagarin’s flight, but his identity was kept a state secret during his lifetime, and he died in 1966 before the Moon missions. The gift was a quiet acknowledgment of his role.
The display holds about 0.2 grams of lunar material in three fragments. The central one is basalt, a volcanic rock typical of the Moon’s dark plains. The two others are bits of lunar soil fused together by tiny meteorite impacts, with glassy coatings.
For sale, twice
After the Soviet Union collapsed, Koroleva sold the display at Sotheby’s in December 1993. It was the first time any piece of another world had been offered for sale to the public. An American collector bought it for $442,500.
Twenty-five years later, the same collector put it up for auction again. The pieces, the largest measuring about 2 by 2 millimeters and the smallest about 1 by 1 millimeter, sold for $855,000, nearly double the 1993 price. The buyer was another private American collector.
Why they’re so rare
Moon rocks are among the rarest objects on Earth, and almost none are privately owned. The Apollo samples belong to the US government, and selling them is illegal. Lunar samples given to other countries as goodwill gifts belong to those nations.
That makes the Luna 16 grains unique. According to Sotheby’s, they are the only known documented lunar samples returned by a spacecraft that are legally in private hands.
There are other ways to own a piece of the Moon. Lunar meteorites, chunks blasted off the Moon by impacts that later fell to Earth, can be bought and sold legally. But they reached Earth on their own, not on a spacecraft.
A robotic revival
Robotic sample return didn’t end with the Soviets. China’s Chang’e 5 mission brought back about 1.7 kilograms of lunar material in 2020. In 2024, Chang’e 6 returned the first samples ever collected from the Moon’s far side.
Those missions follow the path Luna 16 opened more than 50 years ago. Its few specks in a collector’s case are a reminder of how hard it once was to bring back even a single gram of the Moon.