Question

21. How long does it take a star to get back to the same position in the sky it was the night before?

Answer 1

Answer: 23 hrs 56 min

Explanation: Because the earth rotates a full rotation in 24 hrs so the star will be in the same spot just before the full rotation is done.

one can measure time by the fractional distance a star has gone in its full circle around the sky. This is best done for stars that never set, stars near the north celestial pole.