Could Mars soil block Earth microbes? 'Water bears' offer a clue‎

Tardigrades, commonly known as water bears, may be better suited by a new name: Tardiguardians of the Galaxy. Unlike the fictional ragtag team of unenthusiastic heroes, the microscopic animals are providing real insight into how humans could adapt extraterrestrial resources to support space exploration, as well as whether such resources could help protect against the Earthly contaminants that humans might shed.