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Did Mars Ever Look Like Earth?

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We Asked a NASA Scientist.

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Well, yes it did. Whenever the solar system first\h
formed over four billion years ago, Mars and

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Earth formed out of the same stuff and so they\h
looked very similar. While today, whenever we look

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at Mars, we see a very dry planet as compared\h
to the Earth, which is you know our blue marble,

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we see evidence of past lakes and streams.\h
It may have even had a shallow northern ocean.

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However, they diverged and we have\h
two very different planets today.

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As the Earth progressed with plate\h
tectonics and the development of life,

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Mars' geologic activity subsided, lost that water\h
and it became a much drier planet.

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That's part of why it's so fascinating to study Mars and\h
that helps us understand more about Mars' past

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and future, as well as understanding Earth and\h
planetary evolution both in our solar system

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and beyond. So, did Mars ever look like Earth?\h
Well, yes it did. A very, very long time ago.