Image: Wikimedia Commons

celestial equator

Projection of the Earth's equator out into space

Entitycircle of latitude reference pointQ187646

Instance of: circle of latitude
, reference point
Subclass of: equator

Overview

From Wikipedia, the free encyclopedia · Read full article · Text CC BY-SA 4.0

The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of a planet, by convention generally Earth. By extension, it is also a plane of reference in the equatorial coordinate system. Because of the Earth's axial tilt, the celestial equator is currently inclined by about 23.44° with respect to the ecliptic, but has varied from about 22.0° to 24.5° over the past 5 million years as a result of Milankovitch cycles and perturbation from other planets.

Overview

All data

16 statements · 19% with external sources · numbers in brackets are citations

Declination: 0 degree
Right ascension: none

On other databases

13 identifiers linking celestial equator across the web's reference databases

Data quality

statements

19%

externally sourced

Source last edited October 11, 2026. AIDB refreshes this page daily.

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AIDB. (2026). celestial equator (Q187646). Retrieved from https://aidb.si/e/celestial-equator-Q187646