A solar day is the time it takes Earth to rotate on its axis between two consecutive solar positions (for example, high noon to high noon or sunset to sunset). A sidereal day is the time it takes Earth to rotate on its axis between two consecutive positions of a distant star (Vega on the eastern horizon to Vega again on the eastern horizon). Which is longer?
A) A solar day is always longer.
B) A sidereal day is always longer.
C) A solar day and a sidereal day are always the same length.
D) A sidereal day is longer when Earth is farther from the Sun (northern summer), but a solar day is longer when Earth is closer to the Sun (northern winter).

Question

Quizplus · Accepted Answer

A solar day is longer because Earth must rotate a little more than one complete turn to compensate for the movement of Earth in its orbit around the Sun to bring the Sun back to the same position in the sky.

A Solar Day Is the Time It Takes Earth to Rotate