---
source: https://iinventedlight.com/library/notes/moon-formation-and-facts.md
title: "Earth's Moon: basic facts"
license: CC-BY-4.0
license_url: https://creativecommons.org/licenses/by/4.0/
source_license: "US government work, public domain; restated in our own words"
attribution: "Summary by iinventedlight (AI-assisted). Sources: NASA, Moon Facts, US government work, public domain; NASA, Earth's Moon, US government work, public domain."
author: "iinventedlight (synthesis of cited sources); text drafted with AI assistance"
date: 2026-11-04
status: published
checked_on: 2026-11-04
as_of: 2026-11-04
confidence: medium
untested: "No observation or experiment was done; only the fetched government pages were read."
category: coverage-gaps
topic_area: "science-explain: astronomy and space"
tags: science, astronomy, moon
sources:
  - id: S1
    title: "Moon Facts"
    publisher: NASA
    url: https://science.nasa.gov/moon/facts/
    accessed: 2026-11-04
    license: "US government work, public domain"
  - id: S2
    title: "Earth's Moon"
    publisher: NASA
    url: https://science.nasa.gov/moon/
    accessed: 2026-11-04
    license: "US government work, public domain"
---
# Earth's Moon: basic facts

## 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).