Earth’s rotation mainly causes day and night in the heliocentric model.
As Earth rotates eastward around its axis, different parts of the planet turn toward and away from sunlight. The hemisphere facing the Sun experiences daylight; the hemisphere turned away experiences night. Earth completes one rotation relative to the distant stars in about 23 hours 56 minutes, while the solar day averages 24 hours because Earth also moves along its orbit.
This explanation is central to the heliocentric model. Earth does not need to be stationary while the Sun circles it daily; instead, its own axial rotation produces the apparent daily motion of the Sun across the sky. Earth’s revolution around the Sun explains the year, not the ordinary cycle of day and night.
Precession and nutation are also real motions, but they are much slower changes in the orientation of Earth’s axis. Precession takes roughly 26,000 years, while nutation consists of smaller periodic wobbles. Earth’s revolution is important for seasons and changes in the Sun’s yearly path, but it is not the main cause of the daily alternation between light and darkness.