Astronomers once thought Mars was covered in a network of canals carrying water from the ice caps

There are no little green men on the red planet, but there might just be something alive. Astronomers once thought Mars was covered in a network of canals carrying water from the ice caps. Nineteenth-century researchers imagined seas full of marine life, and even forests: a new new world, and not a friendly one. Martians invaded Earth in HG Wells's novel

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