[meteorite-list] Mars Rovers Near Five Years of Science and Discovery

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Mon, 29 Dec 2008 14:25:10 -0800 (PST)
Message-ID: <200812292225.OAA00611_at_zagami.jpl.nasa.gov>

Dec. 29, 2008

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: 08-337

Mars Rovers Near Five Years of Science and Discovery

PASADENA, Calif. -- NASA rovers Spirit and Opportunity may still have
big achievements ahead as they approach the fifth anniversaries of
their memorable landings on Mars.

Of the hundreds of engineers and scientists who cheered at NASA's Jet
Propulsion Laboratory (JPL), in Pasadena, Calif., on Jan. 3, 2004,
when Spirit landed safely, and 21 days later when Opportunity
followed suit, none predicted the team would still be operating both
rovers in 2009.

"The American taxpayer was told three months for each rover was the
prime mission plan," said Ed Weiler, associate administrator for
NASA's Science Mission Directorate at NASA Headquarters in
Washington. "The twins have worked almost 20 times that long. That's
an extraordinary return of investment in these challenging budgetary
times."

The rovers have made important discoveries about wet and violent
environments on ancient Mars. They also have returned a
quarter-million images, driven more than 13 miles, climbed a
mountain, descended into craters, struggled with sand traps and aging
hardware, survived dust storms, and relayed more than 36 gigabytes of
data via NASA's Mars Odyssey orbiter. To date, the rovers remain
operational for new campaigns the team has planned for them.

"These rovers are incredibly resilient considering the extreme
environment the hardware experiences every day," said John Callas,
JPL project manager for Spirit and Opportunity. "We realize that a
major rover component on either vehicle could fail at any time and
end a mission with no advance notice, but on the other hand, we could
accomplish the equivalent duration of four more prime missions on
each rover in the year ahead."

Occasional cleaning of dust from the rovers' solar panels by Martian
wind has provided unanticipated aid to the vehicles' longevity.
However, it is unreliable aid. Spirit has not had a good cleaning for
more than 18 months. Dust-coated solar panels barely provided enough
power for Spirit to survive its third southern-hemisphere winter,
which ended in December.

"This last winter was a squeaker for Spirit," Callas said. "We just
made it through."

With Spirit's energy rising for spring and summer, the team plans to
drive the rover to a pair of destinations about 200 yards south of
the site where Spirit spent most of 2008. One is a mound that might
yield support for an interpretation that a plateau Spirit has studied
since 2006, called Home Plate, is a remnant of a once more-extensive
sheet of explosive volcanic material. The other destination is a
house-size pit called Goddard.

"Goddard doesn't look like an impact crater," said Steve Squyres of
Cornell University, in Ithaca, N.Y. Squyres is principal investigator
for the rover science instruments. "We suspect it might be a volcanic
explosion crater, and that's something we haven't seen before."

A light-toned ring around the inside of the pit might add information
about a nearby patch of bright, silica-rich soil that Squyres counts
as Spirit's most important discovery so far. Spirit churned up the
silica in mid-2007 with an immobile wheel that the rover has dragged
like an anchor since it quit working in 2006. The silica was likely
produced in an environment of hot springs or steam vents.

For Opportunity, the next major destination is Endeavour Crater. It is
approximately 14 miles in diameter, more than 20 times larger than
another impact crater, Victoria, where Opportunity spent most of the
past two years. Although Endeavour is 7 miles from Victoria, it is
considerably farther as the rover drives on a route evading major
obstacles.

Since climbing out of Victoria four months ago, Opportunity has driven
more than a mile of its route toward Endeavour and stopped to inspect
the first of several loose rocks the team plans to examine along the
way. High-resolution images from NASA's Mars Reconnaissance Orbiter,
which reached Mars in 2006, are helping the team plot routes around
potential sand traps that were not previously discernable from orbit.

"The journeys have been motivated by science, but have led to
something else important," said Squyres. "This has turned into
humanity's first overland expedition on another planet. When people
look back on this period of Mars exploration decades from now, Spirit
and Opportunity may be considered most significant not for the
science they accomplished, but for the first time we truly went
exploring across the surface of Mars."

For more information about Spirit and Opportunity, visit:

http://www.nasa.gov/rovers .
        
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Received on Mon 29 Dec 2008 05:25:10 PM PST