The Sun is the primary object in the sky used to determine local time, known as Apparent Solar Time . The actual positions and motions of celestial bodies, including the sun, are tracked relative to Earth's rotation. Astronomers, however, prefer to use sidereal time, where a star rises at the same time every day. ;
The Sun is the key object used to determine local time through Apparent Solar Time, which is based on its position in the sky. Local solar noon, when the Sun is highest in the sky, marks the basis for clock time, though the solar day can vary slightly due to Earth's orbit. Astronomers often use Sidereal Time for more consistent observations of celestial bodies.
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