celestial equator


noun Astronomy, Navigation.

the great circle of the celestial sphere, lying in the same plane as the earth's equator.

Origin of celestial equator

First recorded in 1870–75

British Dictionary definitions for celestial equator

celestial equator

noun

the great circle lying on the celestial sphere the plane of which is perpendicular to the line joining the north and south celestial poles Also called: equinoctial, equinoctial circle

Scientific definitions for celestial equator

celestial equator

A great circle separating the northern and southern hemispheres of the celestial sphere and lying in the same plane as the Earth's equator. The celestial equator is a projection of the Earth's equator outward onto the celestial sphere and is used as the reference point in determining a celestial body's declination.