essentials

How old is the Earth?

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essentials

Earth is approximately 4.54 billion years old. Scientists determined this age by studying radioactive elements in rocks and meteorites.

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essentials

How old is the universe and how do we know?

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essentials

The universe is approximately 13.8 billion years old. Scientists determined this by measuring the leftover radiation from the Big Bang and observing how fast galaxies are moving away from each other.

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