Equinox (celestial coordinates): Difference between revisions

Undid addition of infobox. Image hard to read and meaning unclear.
(Undid addition of infobox. Image hard to read and meaning unclear.)
{{About|the celestial coordinate system|the moment when the Sun is positioned directly over the Earth's equator and, by extension, the apparent position of the Sun at that moment|Equinox}}
{{Use mdy dates|date=April 2014}}
|title=Location of Vernal Equinox
|image= [[File:Location of Equinox.png|250px]]
|caption= Location of the J2000.0 vernal equinox direction as projected on the [[celestial sphere]]. Depicted in [[Equatorial coordinate system|equatorial]] (above) and [[Ecliptic coordinate system|ecliptic]] (below) [[celestial coordinate system|celestial coordinate systems]]. The vernal equinox direction, located in the Pisces constellation, defines the primary direction (0° longitude) in both these systems.
In [[astronomy]], '''equinox''' is a moment in time at which the vernal point, [[celestial equator]], and other such elements are taken to be used in the definition of a [[celestial coordinate system]]. The position at other equinoxes can be computed by taking into account [[precession]], [[nutation]] and [[aberration of light|aberration]], which directly affect e.g. [[right ascension]] and [[declination]].