Stay On Target: NASA's Rover Reaches Huge Crater On Mars

You may not have realized it, but a piece of U.S. property was recently driving around on the surface of Mars. Tens of millions of miles away from the debt crisis, the heat wave and other big events of the summer, NASA's rover Opportunity just completed a 13-mile trip to allow scientists to examine a Martian crater.

It took the golf-cart-sized rover more than two years to reach the Endeavour crater, after it explored a similar, smaller crater. Opportunity reached that crater, Victoria, in 2009. That's also when its twin rover, Spirit, became stuck in the silty light soil of Mars. The Road to Endeavour website has been tracking Opportunity's progress.

With a diameter of 14 miles, Endeavour is expected to hold rocks and terrain that are distinct from anything the rovers have seen as of yet. Scientists have been eager to study the crater, which seems to hold clay minerals that NASA says "may have formed in an early warmer and wetter period."

Explaining why Endeavour's rocks are different, Mars Exploration Rover science team member Matthew Golombek says, "Clay minerals form in wet conditions, so we may learn about a potentially habitable environment that appears to have been very different from those responsible for the rocks comprising the plains."

The Mars rovers have far exceeded expectations for its planned three-month mission. A news release from NASA explains:

NASA launched the Mars rovers Spirit and Opportunity in the summer of 2003. Both completed their three-month prime missions in April 2004 and continued years of extended operations. They made important discoveries about wet environments on ancient Mars that may have been favorable for supporting microbial life.

In a piece for NPR's 13.7 blog, Marcelo Gleiser wonders if humans should take part in space missions of the future, or let the machines have all the fun.

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