Mars Exploration Rover Update - April 17, 2004

http://marsrovers.jpl.nasa.gov/mission/status.html

OPPORTUNITY UPDATE: Record-Setting Drive - sol 81 & 82,
Apr 17, 2004

Three days after switching to new software with
mobility-enhancing features, NASA's Opportunity shattered
the record for a single day's driving on Mars. The rover
covered 140.9 maters (462 feet) during its 82nd sol on Mars,
ending at 2:15 p.m. PDT, Saturday, May 17. That is about
40 meters farther than either the best previous one-day drive,
by Opportunity two weeks ago, or the total distance covered
by NASA's smaller Sojourner rover during its entire three-month
mission in 1997.

The first 55 meters (180 feet) was done as a "blind" guided
drive based on images acquired previously. Speed during that
session averaged 120 meters (394 feet) per hour. For the rest,
Opportunity used autonomous navigation, watching for obstacles,
choosing its own path, and averaging 40 meters (131 feet) per
hour. After the drive, the rover took forward-looking images
for planning the next drive.

On the previous martian day, sol 81, Opportunity awoke with its
alpha particle X-ray spectrometer on a soil target called
"Beagle Burrow" inside a trench the rover had dug on sol 73.
The rover removed the instrument arm, stowed it, then backed up
to image the trench before driving toward a crater nicknamed
"Fram Crater." Opportunity then completed a 7.5-meter (24.6-foot)
drive to a trough to image a rock outcrop within it with the
panoramic camera. After a bit of guided driving, the rover set
out using its autonomous navigation. The sol 81 drive totaled
more than 40 meters (131 feet).

Nearly reaching the second of four waypoints on the way to Fram
Crater, the rover imaged its new surroundings to identify any
future driving hazards. An afternoon nap preceded sol 81's final
science session, atmospheric observations with the miniature
thermal emission spectrometer and the panoramic camera.

Rover controllers devoted sol 82 to driving after some morning
atmospheric observations and a quick look back with the panoramic
camera. The record-setting run took three hours -- a good time
for a marathon. It brought Opportunity to within about 90 meters
(295 feet) of Fram Crater. It also took Opportunity over the
600-meter threshold, a criterion that had been set for at least
one of the Mars Exploration Rovers to achieve in order for the
mission to be called a success. Opportunity has now traveled
627.7 meters (0.39 mile). Spirit passed the 600-meter threshold
two weeks ago.

Rover wake-up music for sol 82 was "I Would Walk 500 Miles," by
Less Than Jake (originally by the Proclaimers).

For sol 83, ending at 2:54 p.m. PDT, Sunday, April 18, another
drive day is planned for Opportunity, with a goal of getting the
rover close to Fram Crater. Scientists then plan to use
Opportunity for some investigations of that location.