Earth-moon system

Science

Definition

The Earth-Moon system describes the gravitational relationship between Earth and its natural satellite, the Moon. This system produces tides, stabilizes Earth's axial tilt, and creates lunar phases and eclipses as the Moon orbits Earth approximately every 27.3 days.

Examples

  • Ocean tides are caused primarily by the Moon's gravitational pull on Earth's water
  • Solar and lunar eclipses occur when the Sun, Earth, and Moon align precisely
  • The Moon's stabilizing effect on Earth's tilt helps maintain relatively stable seasons over long time periods
Key Fact

The Moon orbits Earth at an average distance of 384,400 km and is slowly moving away at ~3.8 cm per year.

Related Terms

Tides Universal gravitation Orbital motion Solar system

Study This Concept

Practice Earth-Moon system with free review games in these units:

Earth Science Unit 8: Astronomy and Space