Mars Exploration Rover Update - October 31, 2005

http://marsrovers.jpl.nasa.gov/missi...ml#opportunity

OPPORTUNITY UPDATE: Riding Ripples and Working Issues - sol 619-626,
Oct 31, 2005:

Opportunity is healthy and traversing around the northwest side of
"Erebus Crater." The rover has driven on every sol possible, acquiring
during and after each drive, and surveying the sky and horizon in the
mornings with the panoramic camera.

Sol-by-sol summaries:

Sol 619 (Oct. 20, 2005): Opportunity drove 24 meters (79 feet) in a
zigzag pattern to safely cross ripples.

Sol 620: The rover's observations used its panoramic camera to observe
a
feature informally named "Mogollon Rim" (for an area in Arizona) and
onboard magnets. It also checked for dust devils.

Sol 621: Opportunity drove 30 meters (98 feet), mostly on sand. The
average slip was only 2.5 percent.

Sol 622: Untargeted observations included a panorama to examine the
amount of light reflected from the surface and a ground survey. A
software glitch resulted in losing the afternoon communication relay
session with Mars Odyssey. The problem was a repeat of one experienced
previously on Spirit's sols 131 and 209 and on Opportunity's sol 596.
It
occurs when a "write" command reaches an area of memory during a
vulnerability period of a few microseconds when that memory location
cannot accept a new write command. The rover team is investigating the
problem.

Sol 623: This was a recovery sol. Opportunity returned data directly to
Earth during an X-band communication window after calibration of the
high-gain antenna. It also performed a calibration of the panoramic
camera mast assembly (the rover's "head") to regain use of it and to
stow the camera. One of the rover's two batteries would not recharge,
which at first puzzled the team. A switch that allows battery 1 to
recharge was not enabled, so the battery was temporarily unable to
recharge. On the following morning (sol 624), the switch was enabled
and
the battery subsequently operated normally. Engineers' analysis
indicates that recharging was not enabled on sol 623 because the rover
did not use enough electricity from the battery during the previous sol
(622) to draw the battery's charge below a level pre-set as a threshold
for allowing a recharge.

Sol 624: The rover drove and used the panoramic camera to look at its
tracks. It covered 27.3 meters (nearly 90 feet).

Sol 625: At the end of sol 624, Opportunity found itself in an area
with
relatively small ripples. In this benign terrain, it was given commands
for a drive that included a segment of autonomous navigation after an
approximately 30-meter (98-foot) segment of blind driving. Preliminary
analysis shows a total distance of 45.7 meters (150 feet) was
traversed.

Sol 626: For this sol the team planned another drive, with about 30
meters (98 feet) expected.

Opportunity's total odometry as of sol 625 (Oct. 27, 2005) is 6,265
meters (3.89 miles). This week (sols 619 to 625), the rover drove 127
meters (417 feet).