Day and night: what we know and how we know
Physics Narrative for 5-11
Day and night
The cycle of day and night is caused by the rotation of the Earth as it spins on it axis once every 24 hours. Because of this spinning motion, the Sun appears to move through the sky but in reality it is the Earth that does the moving.
This effect is like being on a train when the train next to you starts moving. Often you think you are moving only to realise, when you look out of the other window, that it is the other train that is pulling away.