Extraterrestrial life
life which did not originate on Earth
Extraterrestrial life or
alien life is life which may occur outside Earth and which
did not originate on Earth. No extraterrestrial life has yet been
conclusively detected, although efforts are under way. Such life might
range from simple forms such as prokaryotes to intelligent beings,
possibly bringing forth civilizations that might be far more advanced
than humanity. The Drake equation speculates about the existence of
sapient life elsewhere in the universe. The science of
extraterrestrial life is known as astrobiology.
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