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  1. Home
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  3. Astronomical Unit
General

Astronomical Unit

Definition

A unit of measurement equal to the average distance between Earth and the Sun, approximately 149.6 million kilometers (93 million miles). It is commonly used to express distances within our solar system. Jupiter orbits at about 5.2 AU from the Sun.

Related Terms

Light-Year

The distance light travels in one year in a vacuum: approximately 9.461 trillion km. Used to express astronomical distan...

Parsec

A unit of distance equal to about 3.26 light-years (30.9 trillion km). Derived from parallax of one arcsecond. Professio...

Aphelion

The point in the orbit of a planet, asteroid, or comet at which it is farthest from the Sun. Earth reaches its aphelion ...

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