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Hi, I'm Zola with another NASA fact.

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Why do astronauts float around in the ISS, our International Space Station?

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Because there isn't any gravity up there?

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No. Gravity at the ISS is still nine-tenths what it is on Earth.

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Then how do astronauts in space float and feel weightless?

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The Earth's mass is about a trillion billion elephants.

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That pulls you downward, and that's gravity.

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You feel weight when the floor pushes up on you to keep you from falling downward toward the Earth's center.

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How do you feel when you're in an elevator that starts going down really fast?

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Almost like I weigh less for a new suit.

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Exactly. Because both you and the elevator are falling.

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Are astronauts in the ISS falling?

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Yes. As astronauts in the ISS circle the Earth, they are falling freely toward the Earth and feel almost weightless.

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To learn more, visit our website.

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Until next time, I'm Zola with another cool NASA fact.