Final answer:
The stars appear to move across the night sky because Earth rotates on its axis, creating the illusion of the celestial sphere turning. This movement is regularly observed as stars rise in the east and set in the west, while the celestial poles remain stationary due to their alignment with Earth's rotation axis. The phenomenon is visualized using a planetarium.
Step-by-step explanation:
The stars on the celestial sphere appear to move during the night because of the Earth's rotation on its axis. This daily rotation causes the Sun, Moon, and stars to rise and set with what seems like clockwork regularity. However, while we imagine them on a celestial dome for convenience, these celestial objects are at greatly varying distances from us. As Earth spins, the night sky seems to turn, bringing different stars into view and causing most of them to rise in the east and set in the west. This movement is uniform for all the fixed stars, leading the ancient Greeks to conceptualize the sky as a rotating sphere, a notion that is simplified today with the use of a planetarium.
In addition to Earth's rotation, the apparent motion of the celestial sphere also depends on your latitude. The celestial poles, which align with Earth's axis, appear stationary in the sky. On the other hand, meteors - which are just small pieces of cosmic dust burning up in Earth's atmosphere - move in a different manner, not being part of the celestial rotation pattern.
The concept of the celestial sphere and Earth's rotation was clarified with the experiment by the French physicist Jean Foucault, using a pendulum in 1851, which demonstrated Earth turning beneath it.