Why do planetary bodies rotates around axis. Which force is causing this rotation and why. Also are the stars rotating as well and do planets orbit them because they are rotating or is there some other reason.
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I’d add that gravity and collissions tend to, when given enough time, simplify an early proto-solar system into a 2D plane. Initially, you might have a sphere of dust, gas and small particles. Most of the suff gathers in the center and starts to form a star, while a small part of that stuff was moving too fast and remains in orbit.
That sphere of matter was never perfectly uniform, but had fluctuations in density. The spots with high density pull stuff more than the spots with lower density. As the stuff that didn’t form the star must be moving and orbiting – else it would fall into the star or escape the system – and since orbits are 2D, when the stuff starts to be pulled to these high density spots around the star you end up with a 2D plane.
When the stuff gets pulled together, it collides and tends to e.g. add angular velocity (rotation) to the other object. Because most major objects must be orbiting on the same to plane, to the same direction, on average the rotation ends up on an axis perpendicular to the plane of the solar system.
A few drawings would help for sure, but if you consider how gravity works, how collisions work and how (almost) all stuff around the star must be orbiting to the same direction, it might start to make sense why stuff also rotates.
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