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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Tidal forces between the Earth and Moon are slowing the Earth down and pushing the Moon further away.
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The Space Shuttle main engine weighs 1/7th as much as a train engine but delivers as much horsepower as 39 locomotives.
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More than 20 million meteoroids enter Earth's atmosphere every day.
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Some asteroids have other asteroids orbiting them.
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An international team of astronomers has spotted the farthest known gravitational lens and, as Albert Einstein predicted, it is a galaxy that deflects and intensifies the light of a much further object.
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