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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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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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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