How to keep humans from ruining the search for life on Mars
Microbes from Earth might complicate human junkets to the Red Planet
MUCKING UP MARS Scientists are racing to figure out how to keep astronauts and potential life on Mars safe from one another before humans arrive at the Red Planet.
SpaceX/Flickr
T he Okarian rover was in trouble. The yellow Humvee was making slow progress across a frigid, otherworldly landscape when planetary scientist Pascal Lee felt the rover tilt backward.