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I know that Earth is always falling towards the Sun, but due to its sideways momentum it just misses always. But how did it all start? To go into detail, when the gas cloud with zero angular momentum collided, our solar system was made with planets and sun having their own angular momentum which makes them rotate. But how did the revolution start in the beginning? Were they placed in such a position and distance that they started attracting each other but how ? .They were having only rotation . But a revolution started which forced them to follow a elleptical path so how this happened in the beginning? Did some external force act on them and revolution started? How was this revolution started?
i have assumed dust cloud was having zero angular momentum but it can have any value that does not affect the question i think ?