When viewed from Earth, the celestial sphere (the background of stars) moves east to west on a daily basis. This motion is caused by the
A) rotation of Earth on its axis.
B) revolution of Earth around the Sun.
C) motion of the Sun through the Galaxy.
D) motion of the stars around the galactic center.

Question

Quizplus · Accepted Answer

The apparent east to west motion of the celestial sphere as observed from Earth is primarily due to the Earth's rotation on its axis. This rotation causes the sky to appear as if it is moving, while in reality, it is the observer on Earth who is moving.

When Viewed from Earth, the Celestial Sphere (The Background of Stars)