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  3. Eclipse
Observational Astronomy

Eclipse

Definition

An astronomical event when one celestial body moves into the shadow of another. Solar eclipses occur when the Moon passes between Sun and Earth; lunar eclipses when Earth passes between Sun and Moon. Total solar eclipses briefly turn day into night.

Related Terms

Orbit

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

Moon Phases

The different appearances of the Moon over a synodic month (about 29.5 days). The eight phases are new moon, waxing cres...

Solar Corona

The outermost layer of the Sun's atmosphere, extending millions of kilometers. Much hotter than the surface at 1-3 milli...

Explore Related Topics

Dive deeper into eclipse and related concepts on Cosmos Observatory.

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Visible planets, moon phase, and sunrise times.

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Full Glossary

Browse all 66+ space and astronomy terms.

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