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sidereal day:see sidereal timesidereal time
(ST), time measured relative to the fixed stars; thus, the sidereal day is the period during which the earth completes one rotation on its axis so that some chosen star appears twice on the observer's celestial meridian.
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sidereal dayThe interval between two successive passages of a catalog equinox across a given meridian. It is divided into 24 sidereal hours. The sidereal day is 3 minutes 56 seconds shorter than the mean solar day.
Sidereal day(religion, spiritualism, and occult)
A sidereal day is the period of time it takes for Earth to complete one rotation on its axis with respect to a fixed point in space. Specifically, a sidereal day begins and ends when the local meridian for any given location on Earth passes through 0° Aries (the vernal point). Because of the motion of Earth around the Sun, sidereal days are slightly shorter than ordinary solar days. A sidereal day is 23 hours 56 minutes and 4.09 seconds in length; a sidereal hour is ½4 the length of a sidereal day.