NASA's picked the site for the next Mars rover landing - a spot inside the planet's Gale crater that the scientists say just might reveal whether the planet could have supported life.
The Curiosity rover is due to launch late this year, landing next August at the foot of a mountain in the 96 mile-wide crater. A rocket-powered sky crane suspending Curiosity on tethers will lower the rover directly to the Martian surface.
"Mars is firmly in our sights," says NASA Administrator Charles Bolden. "Curiosity not only will return a wealth of important science data, but it will serve as a precursor mission for human exploration to the Red Planet."
Curiosity will stay on Mars for one Martian year - nearly two Earth years - and will study whether the crater once had the right conditions to support microbial life.
"Scientists identified Gale as their top choice to pursue the ambitious goals of this new rover mission," says Jim Green, director for the Planetary Science Division at NASA Headquarters in Washington. "The site offers a visually dramatic landscape and also great potential for significant science findings."
The Gale crater was selected from more than 30 potential landing sites, and has an alluvial fan likely formed by water-carried sediments. The layers at the base of the mountain contain clays and sulfates, both known to form in water.
"One fascination with Gale is that it's a huge crater sitting in a very low-elevation position on Mars, and we all know that water runs downhill," said John Grotzinger, the mission's project scientist at the California Institute of Technology.
"In terms of the total vertical profile exposed and the low elevation, Gale offers attractions similar to Mars' famous Valles Marineris, the largest canyon in the solar system."
Curiosity's 10 science instruments include two for ingesting and analyzing samples of powdered rock, collected by the rover's robotic arm. Its science payload can identify ingredients of life, such as organic compounds.
But long-term preservation of organic compounds requires special conditions, and finding any is a long shot, says Michael Meyer, lead scientist for NASA's Mars Exploration Program at agency headquarters.
"What adds to Gale's appeal is that, organics or not, the site holds a diversity of features and layers for investigating changing environmental conditions, some of which could inform a broader understanding of habitability on ancient Mars," he says.