Astronomy Answers
From the Astronomical Dictionary

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the sidereal time

The sidereal time is equal to the right ascension that passes through the celestial meridian at that moment. If a given sidereal time (between 0 and 24 hours) returns, then the stars are again in the same places in the sky (seen from the same place on Earth). The sidereal time runs a little faster than ordinary time: 24 hours of sidereal time correspond to 23 hours 56 minutes 4 seconds of ordinary time. Near the equinox of september, the sidereal time and solar time are almost equal.