Glossary

Sidereal day is the time it takes for the Earth to complete one rotation with respect to the stars (using a fixed point) instead of the Sun, which is approximately 23 hours, 56 minutes, and 4.0916 seconds.

Some specialized clocks or timepieces have been designed to display sidereal time, which is based on the Earth's rotation relative to distant celestial bodies. These clocks often feature an additional sub-dial or display screen indicating the current sidereal time, allowing professionals in fields such as astronomy and navigation to track astronomical events with precision.