When you throw a ball. it moves away from you and falls to the ground.  If you throw the ball slowly, it lands on the ground a few feet from you,  If you throw it faster, it will fall farther away.  The faster you throw the ball, the farther it goes.

Now imagine throwing the ball so fast that its path has the same shape as the curvature of the Earth.  Since the Earth is round, the ball you threw would :fall: all the way around the planet.  If it goes just fast enough to keep going around and around, the ball would stay in orbit.  The planets stay in orbit around the sun in the same way.

You may know that all material objects have a gravitational pull.  That includes very small objects, such as buttons and paper clips, as well as very large objects, such as stars and planets,  The amount of gravity depends on the amount of matter.  So buttons would have only a very tiny gravitational force while planets have much larger ones.

While it is true that planets do affect each other's orbits, the effects are actually very small as compared to the sun's.  That is because the sun is over 150 times more massive than all the planets put together!  So, the planets will continue to fall around and around the sun for many more millions of years to come.

Pamela Gray contributed to this article.

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