A sunrise is not the Sun climbing into the sky. It is Earth rotating, carrying a particular location from night into the incoming beam of sunlight. The horizon acts as a moving boundary between the lit side of the planet and the side in shadow, so the Sun appears to emerge from below it.
In physical terms, the effect comes from constant angular velocity around Earth’s axis combined with the observer’s local frame of reference. Because the ground under an observer rotates eastward, the Sun seems to move in the opposite direction. The light field is essentially fixed at a large distance, but the spinning surface creates the visual progression from darkness to dawn.
This relative motion also explains why the Sun appears to rise, arc overhead and set along a predictable path tied to latitude and axial tilt. Atmospheric refraction slightly bends sunlight, allowing the Sun to be seen when it is still geometrically below the horizon. The daily event remains a stable cue, even though the actual movement belongs to Earth, not to the Sun.
