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The Invisible Force


We all learned that gravity is the force that keeps us on Earth. If you jump, you won't fly to outer space because the force of gravity pulls you back to Earth. But did you know that gravity is one of the forces that keep the Moon moving around Earth? Gravity also helps Earth revolve around the Sun!

The Moon moves around Earth in an orbit. An orbit is a path an object follows as it revolves. Follow the path the Moon takes as it revolves around Earth. Why do you think the Moon doesn't fly off to the side?

Earth also revolves around the Sun in an orbit. Follow the path Earth takes as it revolves around the Sun. Why doesn't Earth fly off to the side? What makes Earth stay in an orbit around the Sun?

Let's do an Activity to see why both the Moon and Earth stay in their orbit and do not fly off to the side.
(click the word "Activity" above to go to the activity page.)



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