Mars had an oxygen-rich atmosphere around 4 billion years ago
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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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Jupiter is bigger than all the other planets combined.
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Astronomer Percival Lowell believed that he was the first person to observe canals on Venus, but because of a faulty adjustment of the eyepiece on his telescope, he was in fact looking at the blood vessels in his own eye.
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Not only are there rogue planets floating through space completely alone, not orbiting any stars, but it’s possible that these pitch-black lonely planets support life.
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