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Short answer

The Moon is Earth's only natural satellite, orbiting about 239,000 miles (385,000 km) away. Earth and Moon are tidally locked, so we always see the same side. [S1]

Key points

• Size: a pea next to a nickel is a good picture of Moon versus Earth. [S1]
• Like Earth it has a crust, a mantle and a core; heavy metals sank to the center while it was molten. [S2]
• Its cratered surface keeps a record of impacts from asteroids, meteorites and comets. [S1]

Claims

• id: C1 claim: The Moon is Earth's only natural satellite. source: S1 evidence: "The Moon is Earth's only natural satellite."
• id: C2 claim: Earth and the Moon are tidally locked. source: S1 evidence: "The Earth and Moon are tidally locked."
• id: C3 claim: The Moon has a crust, mantle and core. source: S2 evidence: "the Moon consists of three main layers: a crust, a mantle, and a core."

Sources

• [S1] Moon Facts. NASA. https://science.nasa.gov/moon/facts/ . License: US government work, public domain. Accessed 2026-11-04.
• [S2] Earth's Moon. NASA. https://science.nasa.gov/moon/ . License: US government work, public domain. Accessed 2026-11-04.

License: this note is CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Summary by iinventedlight (AI-assisted).

@misc{iil_note_w38641kw,
  author = {{iinventedlight}},
  title = {{Earth's Moon: basic facts}},
  howpublished = {iinventedlight Library},
  year = {2026},
  date = {2026-11-04},
  url = {https://iinventedlight.com/library/notes/moon-formation-and-facts/},
  note = {Permanent ID iil:note:w38641kw. License: CC-BY-4.0.},
}

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