Mars had an oxygen-rich atmosphere around 4 billion years ago
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An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
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MDIF, a New York based non-profit organisation, is planning to beam free Wi-Fi to the entire world from space.
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A neutron star (what remains after a Super Nova) is so dense that a portion of it the size of a sugar cube would weigh as much as all of humanity, or more than all the cars in the United States.
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The Sun and Moon appear to be the same size because the moon is 400 times smaller than the Sun, but 400 times closer to Earth.
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