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So, how much does the Earth weigh? We don't know for sure, but we do know it weighs a lot more than any of us!
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Courtesy of NASA

Did the Earth Lose Weight?
News story originally written on May 2, 2000

Do you know how much the Earth ways? Scientists think they may know. We can't put a really big scale under the Earth and measure it. So, how do scientists know what it ways?

They actually use math! One of the things scientists need to know is the force of gravity. Gravity is a very tricky thing to measure, and scientists weren't really sure what it is.

But now they have measured the force of gravity, so they also know the weight of Earth! Well, at least they think so. Other scientists have to do the experiment again before we know for sure.

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