Lunar meteorite

A lunar meteorite is a special kind of meteorite that comes from the Moon. These space rocks are thrown off the Moon when something, like another space rock, hits it very hard. This sends pieces of the Moon into space, and sometimes these pieces fall to Earth.

When a meteorite hits the Moon, it can create a flash of light or a shadow that people on Earth can sometimes see. These events are called transient lunar phenomenon. Scientists study lunar meteorites to learn more about the Moon’s surface and its history.

Lunar meteorites are very rare and valuable for scientists because they give us pieces of the Moon to study. By looking at these rocks, we can discover important information about how the Moon formed and changed over time.

Discovery

In January 1982, John Schutt found a special meteorite in Antarctica during an expedition for the ANSMET program. The meteorite, called Allan Hills 81005, was sent to Washington, DC. There, Brian Mason, a scientist at the Smithsonian Institution, noticed it looked like rocks brought back from the Moon by the Apollo program.

Later, Japanese scientists found another lunar meteorite, Yamato 791197, in Antarctica in 1979. By July 2019, 371 lunar meteorites had been discovered. These meteorites come from the Moon and have been found mostly in deserts, especially in Antarctica, northern Africa, and the Sultanate of Oman. None have been found in North America, South America, or Europe. Scientists know they come from the Moon by comparing their composition to samples collected by Apollo missions.

Transfer to Earth

Most lunar meteorites come from the Moon. They are sent away when space rocks crash into the Moon and make craters. We do not know which craters these meteorites came from, but some think a special meteorite named Sayh al Uhaymir 169 might have come from a crater called Lalande on the side of the Moon that faces Earth.

Scientists have studied these meteorites and found that they all left the Moon in the last 20 million years. Most of them left in the past 100,000 years. After leaving the Moon, many of these space rocks move around Earth and fall down because of Earth's gravity. Some meteorites go into orbits around the Sun. They stay in space for a longer time, but they will eventually come close to Earth and land on our planet.

Scientific relevance

The six Apollo missions only collected samples from one part of the Moon. Lunar meteorites come from many different places on the Moon, so they help us learn more about its surface. About half of these meteorites likely came from the far side of the Moon, which we have not visited.

When the first lunar meteorite was found in 1982, it helped scientists think that rocks from Mars might also reach Earth. Some scientists wonder if we might find very old rocks from Earth on the Moon.

Observation history

About one in every thousand new meteorites comes from the Moon. Most meteorites are from the asteroid belt. In the early 1800s, many scientists thought all meteorites came from the Moon. Some people still think small glass pieces called tektites might come from the Moon, but most scientists disagree.

Private ownership

Lunar meteorites found in Africa and Oman are the main way for people to own pieces of the Moon. Rocks brought back by the Apollo missions belong to the United States government or other countries. Meteorites collected by the U.S. and Japan in Antarctica are kept for research. While there is no law stopping private ownership of these rocks, the U.S. government has never sold any to the public. Special plaques with Moon rocks given to astronauts and Walter Cronkite still kept the rocks under NASA's ownership. Most samples from the Luna 16 probe are not available for private ownership.