How come the earth rotates?

Answer 1

It is believed by scientists that the solar system as we know it originally condensed

out of an interstellar cloud of dust and gas, some four and a half billion years ago.

Because the cloud was rotating, that angular momentum now appears in the form of

the various different rotating and orbiting objects in the solar system. You may also

extend the question further back in time, to ask why the original cloud was rotating.

This would be a byproduct of the Big Bang. All the momentum in the universe can

ultimately be traced back to that event.

Some people would prefer a different explanation. We might hypothesize that God

caused the Earth to rotate because if the Earth did not rotate, it would get too hot

on the sunlit side and too cold on the dark side, and that would not allow for the kind

of happy planet that God had in mind.

Another contributor observed:

Notice that there is no conflict between these two answers, and in fact, it's quite

easy to view them as components of one and the same answer. Gcd is the 'what'

and the 'why', and angular momentum, the big bang, and the other laws of Physics,

such as inverse-square gravity and the double helix, are the 'how'.