Popular Science - The search for alien life is on

New missions and discoveries on Earth, within our solar system and beyond are bringing us closer than ever to finding alien life on other planets … The first work starts here at home. By studying life that exists in extreme environments, scientists are learning a great deal about how and where to look for it on other planets.

Researchers have found microbes in volcanic calderas, deep ocean vents and arsenic-laden lakes [see “Scientist in a Strange Land,”], and the existence of these “extremophile” life-forms has redefined the concept of habitability on this planet and elsewhere.

Microbiologist Lyle Whyte of McGill University in Montreal found bacteria living at subzero temperatures in a methane-rich spring on Axel Heiberg Island in the Canadian Arctic Ocean. Similar life-forms could also be the source of the recently discovered methane plumes on Mars. “There could be microorganisms in the deep subsurface of Mars that produce the gas,” Whyte says.