# Revolution of Planets [duplicate]

Why do planets revolve around the sun? I understand that gravity plays a huge role in allowing it to move around. But what caused it to revolve in the first place? One possible solution is explained with the theory of relativity but is there a classical mechanics approach to this question?

• Hi Sumedha - it couldn't be simpler. The sun, planets started from a big cloud of gas. That cloud of gas was spinning - so it's all still spinning. – Fattie Nov 28 '16 at 3:39

Classical mechanics approach to this would be gravitational force as we know F=GMm/r2 and Centripetal force F=mv2/r.