Mars rover Opportunity examining rock changed by water
Washington: NASA's senior Mars rover Opportunity is investigating a rock intensely altered by water.
The fractured rock, called "Esperance," provides evidence about a wet ancient environment possibly favorable for life.
The mission's principal investigator, Steve Squyres of Cornell University, Ithaca, New York, said, "Esperance was so important, we committed several weeks to getting this one measurement of it, even though we knew the clock was ticking."
The mission's engineers at NASA's Jet Propulsion Laboratory, Pasadena, California, had set this week as a deadline for starting a drive toward "Solander Point," where the team plans to keep Opportunity working during its next Martian winter.
"What's so special about Esperance is that there was enough water not only for reactions that produced clay minerals, but also enough to flush out ions set loose by those reactions, so that Opportunity can clearly see the alteration," Scott McLennan of the State University of New York, Stony Brook, a long-term planner for Opportunity's science team, said.
This rock's composition is unlike any other Opportunity has investigated during nine years on Mars-higher in aluminum and silica, lower in calcium and iron.
The next destination, Solander Point, and the area Opportunity is leaving, Cape York, both are segments of the rim of Endeavor Crater, which spans 14 miles (22 kilometers) across.
The planned driving route to Solander Point is about 1.4 miles (2.2 kilometers).
The team identified Esperance while exploring a portion of Cape York where the Compact Reconnaissance Spectrometer for Mars (CRISM) on NASA's Mars Reconnaissance Orbiter had detected a clay mineral.