celestial coordinate system
Imaginary horizontal and vertical lines used to describe the position of an object on the celestial sphere.
North celestial pole
Projection of the North terrestrial pole onto the celestial sphere.
One of two coordinates used to locate a celestial body on the celestial sphere; similar to terrestrial latitude.
Projection of the Sun’s apparent annual path onto the celestial sphere.
One of two coordinates used to locate a celestial body on the celestial sphere; similar to terrestrial longitude.
Projection of a terrestrial meridian onto the celestial sphere.
Imaginary sphere where celestial bodies are observed and positioned.
Projection of the terrestrial Equator onto the celestial sphere; serves as the point of origin for declinations.
Shape of Earth whose coordinates are projected onto the celestial sphere.
Point at which the ecliptic and the celestial equator intersect; serves as the point of origin for right ascensions.
South celestial pole
Projection of the South terrestrial pole onto the celestial sphere.
Imaginary circle surrounding Earth at its widest circumference, dividing it into two hemispheres: the Northern hemisphere and the Southern hemisphere.
Angle formed between an imaginary line connecting the terrestrial poles and an imaginary line perpendicular to the ecliptic.