The head of NASA says maybe Pluto is a planet after all. He is wrong because Pluto is part of the rest of the solar system ...

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Deep in the older, denser reaches of the Milky Way, there is a red dwarf star that shouldn’t exist — or at least, its family of planets shouldn’t look the way it does. The star is LHS 1903, and it ...

This Earth Day, we reflect on our home planet and look at Earth from space through history.