Astronomical unit (AU) — Science definition

A distance unit equal to the average distance from Earth to the Sun, about 93 million miles (150 million km); used to keep solar system distances easy to compare.

Where it is taught

• The Solar System — Earth, Moon & Solar System, Earth & Space Science, Grade 9

Taught alongside

• terrestrial planet
• gas giant
• asteroid

Elsewhere

• All science terms
• All courses and reading

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