equatorial coordinates

In astronomy, system for measuring the position of astronomical objects on the celestial sphere with reference to the plane of the Earth's Equator.

Declination (symbol δ), analogous to latitude, is measured in degrees from the Equator to the north (δ = 90°) or south (δ =−90°) celestial poles. Right ascension (symbol α), analogous to longitude, is normally measured in hours of time (α = 0 hours to 24 hours) eastward along the Equator from a fixed point known as the first point of Aries or the vernal equinox.