Jupiter's moon Ganymede, is larger than the planet Mercury!
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Neil Armstrong, the first man to step foot on the moon, carried with him a piece of cloth and wood from the original 1903 Wright Flyer.
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In space, astronauts cannot cry properly, because there is no gravity, so the tears can't flow down their faces!
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Only 55% of Americans know that the sun is a star.
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The Earth gets heavier each day by tons, as meteoric dust settles on it.
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The density of Saturn is so low that if you were to put it in a giant glass of water it would float.
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The Earth weighs around 6,600,000,000,000,000,000,000 tons (5,940 billion billion metric tons)!
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Saturn's rings are about 500,000 miles in circumference but only about a foot thick.
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