Facts About Lunar Craters
Published October 6, 2026 · FactsSeeker
Lunar craters are among the clearest records of the Moon’s long exposure to space. NASA’s Moon facts describe how impacts, weak atmospheric protection, volcanic resurfacing, polar shadows, and water detections all shape what craters can reveal.
Lunar craters are a record of impacts
NASA describes Earth’s Moon as preserving solar-system history through impact craters along with other surface features. For crater studies, that means the surface is not just scenery; it is evidence left by repeated collisions over time. [1]
The impactors include asteroids, meteorites, and comets
The Moon’s surface is solid and rocky, and NASA says it is cratered and pitted by impacts from asteroids, meteorites, and comets. That source list is important because lunar craters are not tied to a single kind of incoming object. [1]
A thin atmosphere lets impacts reach the ground
NASA explains that the Moon’s atmosphere is too sparse to stop incoming impacts. A continuing rain of asteroids, meteoroids, and comets can therefore strike the surface and leave many craters behind. [1]
Tycho is a large named crater
Tycho Crater is described by NASA as more than 52 miles (85 kilometers) wide. It is a clear example of how individual lunar craters can be discussed with measured dimensions, not just as small marks seen from far away. [1]
Impacts helped make the lunar regolith
Over billions of years, impacts have broken the Moon’s surface into pieces ranging from huge boulders to powder. NASA says nearly the entire Moon is covered by lunar regolith, a layer of charcoal-gray dust and rocky debris. [1]
Megaregolith lies beneath the surface rubble
NASA identifies a named layer beneath the loose lunar regolith: fractured bedrock called megaregolith. This matters because crater study is not limited to the visible dust and rocky debris on top; the Moon also has broken bedrock below it. [1]
Some dark lunar plains began as impact basins
The Moon’s dark maria are impact basins that were later filled with lava between 4.2 and 1.2 billion years ago. This means not every impact basin remains only as a simple open depression, because some were altered by volcanic flooding. [1]
Craters preserve a history beyond the Moon
NASA says lunar craters have been preserved for billions of years. Because of that preservation, they provide an impact history for both the Moon and other bodies in the inner solar system. [1]
Polar craters can store important ice
NASA states that the Moon harbors water ice and that the highest concentrations occur within darkened craters at the poles. Those crater settings matter for exploration because NASA links that ice to making the Moon more hospitable for future human colonists. [1]
Permanently shadowed polar regions contain high ice concentrations
NASA reports that missions including Lunar Prospector, LCROSS, and Lunar Reconnaissance Orbiter found global hydration as well as high concentrations of ice water in permanently shadowed regions near the lunar poles. This separates widespread hydration from especially ice-rich shadowed places. [1]
Clavius Crater has confirmed water molecules
In October 2020, NASA’s SOFIA observatory confirmed water on the sunlit surface of the Moon. NASA says SOFIA detected water molecules in Clavius Crater, a large crater visible from Earth in the Moon’s southern hemisphere. [1]
Micrometeoroid strikes can release water from crater material
NASA explains that when micrometeoroids impact the Moon, most of the material in the crater is vaporized. The shock wave can release water coating grains of soil, and most of that water is released into space. [1]
Sources & further reading
Lunar crater evidence includes impact craters preserved for billions of years, lava-modified impact basins, darkened craters at the poles, and sunlit craters with detected water. These categories should not be treated as the same kind of crater environment.
Sources checked 2026-10-01. Our approach to facts · Suggest a correction