Why is it that planets revolve around the sun?
There is a theory that the planets don’t actually “revolve” around the sun. According to Einstein’s theory, any mass warps space around it. (Imagine a heavy lead ball placed on a bed. The surface of the bed will bend/sag below the ball and the ball will sink into a depression. The ball represents the mass, and the bed represents space.) Therefore, the planets, relative to themselves, are actually following a straight line. But since the sun (a mass) warps space around it, the planets appear to follow a circular path around the sun. But to answer your question at our level, any two masses exert gravitation forces on each other (Newton’s Law of Universal Gravitation). Therefore the force of attraction between the sun and the earth is large enough to make the earth veer off from the straight line path that it would have otherwise followed by Newton’s First Law and to make it follow an ellipsis.
