Learn about this topic in these articles:

In galactic coordinate
…plane is defined by the galactic equator, the great circle in the sky best fitting the plane of the Milky Way, as determined by a combination of optical and radio measurements. The galactic equator is inclined at about 62°36′ to the celestial equator, which is the projection of Earth’s Equator…
Read More

celestial coordinates

Table of Contents

Introduction References & Edit History Related Topics

Images

Discover

celestial coordinates

astronomy

Written and fact-checked by The Editors of Encyclopaedia Britannica

Related Topics:: galactic coordinate; hour circle; equatorial system; horizon system; ecliptic system

celestial coordinates, Set of numbers used to pinpoint the position in the sky (see celestial sphere) of a celestial object. Coordinate systems used include the horizon system (altitude and azimuth), galactic coordinates, the ecliptic system (measured relative to the orbital plane of Earth), and the equatorial system (right ascension and declination, directly analogous to terrestrial latitude and longitude).

This article was most recently revised and updated by Erik Gregersen.