There's a mysterious dwarf planet between Mars and Jupiter called 'Ceres' which has never been visited by spacecraft or photographed in detail, however, Earth-bound telescopes reveal a large bright shining spot on the surface of this planet, the origin and nature of which are unknown.
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There is a mysterious and loud radio signal known as 'the space roar' that has yet to be explained.
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Mars had an oxygen-rich atmosphere around 4 billion years ago
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Jupiter's magnetosphere is the largest single structure inside the Solar System. If you could see it with your eyes, it would appear larger than our full Moon.
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Scientists have confirmed that Enceladus, one of Saturn’s moons, has a watery ocean.
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On Titan, Saturn's largest moon, the atmosphere is so thick and the gravity so low that humans could fly through it by flapping "wings" attached to their arms.
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It 'snows' metal on Venus.
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