NASA's Mars Exploration Rover Opportunity passes small crater and big milestone

Opportunity has passed many craters on its crater-hopping tour. One of the youngest of them is "Skylab" crater, which the rover passed last month. Rocks scattered by the impact of a meteorite surround the resulting crater in a view recorded by Opportunity on May 12. The view is at http://photojournal.jpl.nasa.gov/catalog/PIA14132 , and in 3-D stereo at http://photojournal.jpl.nasa.gov/catalog/PIA14133 .

This crater, informally named after America's first space station, is only about 9 meters (30 feet) in diameter. Opportunity passed it as the rover made progress toward its long-term destination, Endeavour crater, which is about 22 kilometers (14 miles) in diameter.

The positions of the scattered rocks relative to sand ripples suggest that Skylab is young for a Martian crater. Researchers estimate it was excavated by an impact within the past 100,000 years.

Opportunity and its twin, Spirit, completed their three-month prime missions on Mars in April 2004. Both rovers continued for years of bonus, extended missions. Both have made important discoveries about wet environments on ancient Mars that may have been favorable for supporting microbial life. Spirit has not communicated with Earth since March 2010.

NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for the NASA Science Mission Directorate, Washington. More information about the rovers is online at: http://www.nasa.gov/rovers .