[meteorite-list] NASA's Mars Rover Opportunity Begins Study of Martian Crater

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu, 1 Sep 2011 13:31:13 -0700 (PDT)
Message-ID: <201109012031.p81KVDNd010857_at_zagami.jpl.nasa.gov>

Sept. 1, 2011

Dwayne Brown
Headquarters, Washington
202-358-1726
dwayne.c.brown at nasa.gov

Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.webster at jpl.nasa.gov
RELEASE: 11-284

NASA'S MARS ROVER OPPORTUNITY BEGINS STUDY OF MARTIAN CRATER

WASHINGTON - The initial work of NASA's Mars rover Opportunity at its
new location on Mars shows surface compositional differences from
anything the robot has studied in its first 7.5 years of exploration.

Opportunity arrived three weeks ago at the rim of a 14-mile-wide
(22-kilometer-wide) crater named Endeavour. The first rock it
examined is flat-topped and about the size of a footstool. It was
apparently excavated by an impact that dug a crater the size of a
tennis court into the crater's rim. The rock was informally named
"Tisdale 2."

"This is different from any rock ever seen on Mars," said Steve
Squyres, principal investigator for Opportunity at Cornell University
in Ithaca, N.Y. "It has a composition similar to some volcanic rocks,
but there's much more zinc and bromine than we've typically seen. We
are getting confirmation that reaching Endeavour really has given us
the equivalent of a second landing site for Opportunity."

The diversity of fragments in Tisdale 2 could be a prelude to other
minerals Opportunity might find at Endeavour. In the past two weeks,
researchers have used an instrument on the rover's robotic arm to
identify elements at several spots on Tisdale 2. Scientists have also
examined the rock using the rover's microscopic imager and multiple
filters of its panoramic camera.

Observations by Mars orbiters suggest that rock exposures on
Endeavour's rim date from early in Martian history and include clay
minerals that form in less-acidic wet conditions, possibly more
favorable for life. Discontinuous ridges are all that remains of the
ancient crater's rim. The ridge at the section of the rim where
Opportunity arrived is named "Cape York." A gap between Cape York and
the next rim fragment to the south is called "Botany Bay."

"On the final traverses to Cape York, we saw ragged outcrops at Botany
Bay unlike anything Opportunity has seen so far, and a bench around
the edge of Cape York looks like sedimentary rock that's been cut and
filled with veins of material possibly delivered by water," said Ray
Arvidson, the rover's deputy principal investigator at Washington
University in St. Louis. "We made an explicit decision to examine
ancient rocks of Cape York first."

The science team selected Endeavour as Opportunity's long-term
destination after the rover climbed out of Victoria crater three
years ago this week. The mission spent two years studying Victoria,
which is about one twenty-fifth as wide as Endeavour. Layers of
bedrock exposed at Victoria and other locations Opportunity has
visited share a sulfate-rich composition linked to an ancient era
when acidic water was present. Opportunity drove about 13 miles (21
kilometers) from Victoria to reach Endeavour. It has driven 20.8
miles (33.5 kilometers) since landing on Mars.

"We have a very senior rover in good health for having already worked
30 times longer than planned," said John Callas, project manager for
Opportunity at NASA's Jet Propulsion Laboratory (JPL) in Pasadena,
Calif. "However, at any time, we could lose a critical component on
an essential rover system, and the mission would be over. Or, we
might still be using this rover's capabilities beneficially for
years. There are miles of exciting geology to explore at Endeavour
crater."

Opportunity and its rover twin, Spirit, completed three-month prime
missions in April 2004 and continued working for years of extended
missions. Both have made important discoveries about wet environments
on ancient Mars that may have been favorable for supporting microbial
life. Spirit ended communications in March 2010.

"This is like having a brand new landing site for our veteran rover,"
said Dave Lavery, program executive for NASA's Mars Exploration
Rovers at NASA Headquarters in Washington. "It is a remarkable bonus
that comes from being able to rove on Mars with well-built hardware
that lasts."

NASA will launch its next-generation Mars rover, Curiosity, between
Nov. 25 and Dec. 18, 2011. It will land on Mars in August 2012. JPL
manages the Mars Exploration Rover Project for NASA's Science Mission
Directorate in Washington.

For more about Opportunity, visit:

http://www.nasa.gov/rovers
        
-end-
Received on Thu 01 Sep 2011 04:31:13 PM PDT