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“solar days”
The interval between two successive noons: Since the Sun is moving across the sky background at a rate of about one degree per day in an easterly direction, the solar day is slightly longer than the sidereal day. Also, the Sun's rate of motion varies, and it is greatest at perihelion.
The mean solar day is equal to 24 hours, 3 minutes, 36.555 seconds.
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Astronomy and related astronomical terms
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