Question

How is solar day different from sidereal day?

Answer 1

A solar day is the time taken by the earth to rotate on its axis so that the sun appears in the same position in the sky, typically 24 hours. A sidereal day is the time taken by the earth to rotate once relative to the stars, which is about 4 minutes shorter than the solar day due to the earth’s orbital motion around the sun. This difference arises because while the earth rotates on its axis, it also moves along its orbit, so it must rotate a bit more for the sun to appear at the same position, making the solar day longer than the sidereal day.