[meteorite-list] NASA's Opportunity Tops 20 Miles of Mars Driving

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue, 19 Jul 2011 14:47:27 -0700 (PDT)
Message-ID: <201107192147.p6JLlR8u016810_at_zagami.jpl.nasa.gov>

http://www.jpl.nasa.gov/news/news.cfm?release=2011-217

NASA's Opportunity Tops 20 Miles of Mars Driving
Jet Propulsion Laboratory
July 19, 2011

More than seven years into what was planned as a three-month mission on
Mars, NASA's Mars Exploration Rover Opportunity has driven more than 20
miles, which is more than 50 times the mission's original distance goal.

A drive of 407 feet (124 meters) completed on July 17 took Opportunity
past the 20-mile mark (32.2 kilometers). It brought the rover to within
a few drives of reaching the rim of Endeavour crater, the rover's team's
long-term destination since mid-2008. Endeavour is about 14 miles (22
kilometers) in diameter, and its western rim exposes outcrops that
record information older than any Opportunity has examined so far. The
rover is now about eight-tenths of a mile (about 1.3 kilometers) from
the site chosen for arriving at the rim.

"The numbers aren't really as important as the fact that driving so much
farther than expected during this mission has put a series of exciting
destinations within Opportunity's reach," said Alfonso Herrera, a rover
mission manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif.
who has worked on the rover missions since before launch in 2003.

The latest drive included an autonomous hazard detection portion during
which the rover paused at intervals to check for obstacles before
proceeding.

Herrera said, "Autonomous hazard detection has added a significant
portion of the driving distance over the past few months. It lets us
squeeze 10 to 15 percent more distance into each drive."

The milestone-setting drive was on the 2,658th Martian day, or "sol," of
the rover's exploration of Mars. Opportunity drove backward. Backward
driving is a technique to extend the life of a motor in the right-front
wheel that sometimes draws more current than the other five wheels'
drive motors.

JPL's Bill Nelson, chief of the mission's engineering team, said,
"Opportunity has an arthritic shoulder joint on her robotic arm and is a
little lame in the right front wheel, but she is otherwise doing
remarkably well after seven years on Mars -- more like 70 in 'rover
years.' The elevated right front wheel current is a concern, but a
combination of heating and backwards driving has kept it in check over
the past 2,000-plus sols."

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

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 .

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

2011-217
Received on Tue 19 Jul 2011 05:47:27 PM PDT