There are tens of billions of Sun-like stars in the Milky Way, an immense tally that encourages the possibility that extraterrestrial life peppers the universe. Finding evidence for aliens - even ...

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There’s no denying the allure of alien artifacts. Science fiction is awash in the material remnants of extraterrestrial civilizations, which surface in everything from the classic books of Arthur C.

Toward the end of 1519, Spanish explorers arrived at the Aztec capital in what is now Mexico City. They were awed by the Aztecs' sophistication and soon demanded the land and resources for themselves.