# Question from an amateur in regards to rotation of sun

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Hi all

I  understand the solar system orbits around the galactic center and the Moon orbits around the Earth, I also understand the central bodies are not "dragging" the orbiting bodies in any sense and they simply maintain the orbit through the gravitational force, according to our current knowledge.

As th example I was given previously by astronomers of a merry-go-round in a playground: as you go around it there is a outward "centrifugal" force which is trying to throw you off; the only reason you don't go flying off is because you are holding onto it. Similarly, with the Earth and the Sun, the Sun's gravity holds the Earth in place as it orbits around and ensures that we don't go flying off into space. However, unlike the merry-go-round which has friction and slows down over time, the Earth meets almost no resistance in space and can orbit indefinitely without slowing down. This is all nice and dandy but it still leaves an unanswered question

So my question is as follows;

Is the Suns' rotation the reason we have years on earth?

The example that I mentioned is a common astronomers example of how we orbit the sun. Yet, this does not explain why we orbit the sun. What gives the planets in our solar system the power to rotate around the sun?

It merely can not be gravity.

So the only possible answer I can seem to conjure up is the rotation of the sun is the reason planets orbit the sun. Is this correct?

When we look at a galaxy, it seems that the core is spinning and bodies are rotating around it due to its motion.

Then when you look at a minor scale the earths rotation seems to be causing the moon to orbit around us. From another perspective, if a planets or the suns rotation did cease, wouldn't that cause the orbiting bodies to break away?

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Is the Suns' rotation the reason we have years on earth?

The example that I mentioned is a common astronomers example of how we orbit the sun. Yet, this does not explain why we orbit the sun. What gives the planets in our solar system the power to rotate around the sun?

It merely can not be gravity.

So the only possible answer I can seem to conjure up is the rotation of the sun is the reason planets orbit the sun. Is this correct?

When we look at a galaxy, it seems that the core is spinning and bodies are rotating around it due to its motion.

Then when you look at a minor scale the earths rotation seems to be causing the moon to orbit around us. From another perspective, if a planets or the suns rotation did cease, wouldn't that cause the orbiting bodies to break away?

No, it's not correct. You are right that gravity cannot propel planets in a circle — in that configuration the force is perpendicular to the motion and can do no work. But it can speed objects up as they move closer to the sun. And gravity, being a force internal to the system, does not change angular momentum. So when the gas and dust coalesced to form the sun and planets, any residual angular motion would remain, and as the objects moved closer, they would speed up. What we're seeing is mainly leftover angular motion from whatever made up the solar system. The rotation of the sun is also a result of that, but not a cause.

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