Facts About the Moon

Published September 16, 2026 · FactsSeeker

The Moon’s familiar face preserves a record of impacts and helps explain the rhythm of our night sky.

12 facts to discoverSee the sources ↓

It rotates while orbiting

The Moon’s rotation period matches its orbital period. This keeps roughly the same side facing Earth. [1]

Both sides receive sunlight. The phrase “dark side” is misleading when used to mean the far side. [1]

A sparse exosphere offers little protection from incoming meteoroids or extreme temperature changes. [1]

The large dark areas called maria formed when lava flooded low-lying regions long ago. [1]

Without Earth-like weather and active surface recycling, many craters remain recognizable for very long periods. [1]

Permanently shadowed regions near the poles can preserve water ice despite the harsh lunar environment. [1]

The Moon is large relative to its parent planet. Its radius is about 1,740 kilometers. [1]

The distance changes during the Moon’s elliptical orbit. The familiar average is about 239,000 miles. [1]

The leading explanation involves a large body colliding with the young Earth. Debris subsequently accumulated into the Moon. [1]

Impacts have ground surface material into fragments and dust. This broken layer is called regolith. [1]

The Moon has a layered interior. Its core is proportionally smaller than those of many other rocky worlds. [1]

Volcanic activity shaped parts of the lunar surface long ago. Those volcanoes have not erupted for millions of years. [1]

Explore the linked source for more detail and the context behind these facts.