Rover to Collect Mars Samples to Send to Earth

Oct. 30, 2007 -- While NASA's next Mars rover scours for signs of habitable environments, it will deposit small pebbles and soil samples into a special cache for a possible return to Earth.

Buoyed by NASA's new science chief Alan Stern, the agency is laying the groundwork for a sample return mission in 2020, said John Grant, co-chairman of the committee working to choose the landing site for the Mars Science Laboratory, or MSL.

Some scientists believe that a sample return mission will be the best way to definitively prove if life ever developed on another planet.

"You look around and can't help but think that life here is unique and special. If you find life elsewhere, that tells you that conditions that existed here...existed somewhere else and that biologically, we're not unique. Philosophically, that has a lot of implications," Grant said in an interview with Discovery News.

"If you've got another planet with life right here in the solar system .. and there are a lot of candidates -- Mars, Europa, Ganymede -- life could be commonplace. It may not be rare or unique," Grant said.

After an initial pot-luck attempt to find life with the Viking missions of the 1970s, NASA embarked on a strategy of following Mars' past water in hopes of finding the best places to search for life.

Mars Science Laboratory, which is scheduled for launch in 2009, is the agency's boldest attempt to hone in on a potential habitat. Scientists last week narrowed a list of 50 candidate landing sites for MSL to their top six picks.

A series of focused observations with orbiters now circling Mars will be conducted to further assess the sites for accessibility and scientific potential, said planetary geologist Matt Golombek, with NASA's Jet Propulsion Laboratory and the MSL landing site committee co-chair.