galactic equator

astronomy

Also known as: galactic circle

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Last updated

June 29, 2026

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The galactic equator is a great circle on the celestial sphere that is parallel to the center line of the Milky Way galaxy. It is inclined approximately 62 degrees to the celestial equator and is used in astronomy to define galactic coordinates.12

Galactic coordinates help locate objects within the Milky Way. Galactic latitude measures how far north or south an object is from the galactic equator, while galactic longitude measures its position eastward from a reference point near the galactic center in the constellation Sagittarius. This system is crucial for understanding the structure and components of our galaxy.23

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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…
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…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