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  3. Perihelion
Planetary Science

Perihelion

Definition

The point in an orbit at which the object is closest to the Sun. Earth reaches perihelion around January 3rd at approximately 147.1 million km. The opposite is aphelion.

Related Terms

Aphelion

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

Orbit

The curved path of a celestial object around a star, planet, or moon under gravity's influence. Orbits can be circular, ...

Astronomical Unit

A unit of measurement equal to the average distance between Earth and the Sun, approximately 149.6 million kilometers (9...

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Full Glossary

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