Mars Exploration Rovers Update - February 16-17, 2006

SPIRIT UPDATE: Spirit Studies Layered Rocks - sol 750-755, Feb 17,
2006:

Spirit will soon be on top of the rugged plateau known as “Home Plate,”
which features the most spectacular layering Spirit has yet
encountered,
and begin taking images of the surrounding terrain. Spirit had a
productive week investigating two rock targets, “Barnhill” and “Posey.”
A restricted planning period (resulting from periodic, limited
opportunities to communicate with overhead satellites) gave Spirit an
opportunity to spend a few sols (Martian days) engaged in untargeted
remote sensing and atmospheric science. The rover also charged its
batteries. The science team is assigning nicknames to surface features
honoring star players and managers of the Negro Leagues of baseball in
the first half of the 20th century.

Sol-by-sol summaries:

Sol 750 (Feb. 11, 2006): Spirit examined a rock target dubbed “Pitcher”
with the microscopic imager, then completed an overnight study of a
rock
target dubbed “Fastball” with the alpha particle X-ray spectrometer.

Sol 751: Spirit stowed the robotic arm and executed a commanded,
5.3-meter (17-foot) drive to Posey using visual odometry. The drive
went
exactly as planned and ended with the rover in place to immediately
begin scientific studies with the robotic arm without further
adjustment
of the rover’s position.

Sol 752: Spirit conducted light remote sensing and recharged the
rover’s
batteries.

Sol 753: Spirit acquired images of a rock target dubbed “Gray” using
the
microscopic imager, brushed a surface target known as “Manager” using
the rock abrasion tool, and completed an 18-hour analysis of Manager
using the Moessbauer spectrometer. The science team opted to complete
an
overnight Moessbauer study before conducting an overnight alpha
particle
X-ray spectrometer study in order to decide how long to stay at this
location. Because the Moessbauer spectrum was similar to that of an
earlier un-brushed target nicknamed Barnhill, the team directed the
rover to resume driving after collecting the alpha particle X-ray
spectrometer data.

Sol 754: Spirit took after-brushing images of Manager with the
microscopic imager, finished the analysis of Manager with the alpha
particle X-ray spectrometer, and took panoramic camera images of
Barnhill.

Sol 755 (Feb. 16, 2006): Before moving on, Spirit rolled back from
Manager and collected data from the site with the miniature thermal
emission spectrometer. The rover paused to take mid-drive images with
the navigation camera before “sliding into” Home Plate after driving 10
meters (33 feet) using visual odometery and 1.5 meters (4.9 feet) using
autonomous navigation.

Odometry:

As of sol 755, Spirit’s total odometry was 6,575 meters (4.09 miles).


OPPORTUNITY UPDATE: Inspecting ‘Bellemont’ - sol 729-735, Feb 16, 2006:

Opportunity has completed its work on the “Olympia” outcrop. This
week’s
activities included a Moessbauer spectrometer integration on target
“Rough Rider,” an alpha particle X-ray spectrometer integration on
target “Fala,” and a short drive to “Bellemont.” Also the rover took
microscopic imager mosaics of four targets at Bellemont. A team
continuing to study occasional problems with the shoulder joint in
Opportunity’s robotic arm planned a series of diagnostic motions for
the
arm for sol 735.

Sol-by-sol summaries:

Sol 729 (Feb. 10, 2006): Opportunity continued using the Moessbauer
spectrometer on Rough Rider and performed targeted remote sensing.

Sol 730: The rover finished using the Moessbauer spectrometer on Rough
Rider, made atmospheric observations, and used the alpha particle X-ray
spectrometer overnight on target Fala.

Sol 731: The rover stowed its arm, made a short drive to Bellemont and
then unstowed the arm. This pattern of stow, drive and unstow is what
the team intends to use for longer drives.

Sol 732: Opportunity used the microscopic imager at Bellemont. Four
targets were identified. Opportunity acquired images of three (“Vicos,”
“Tara” and “Chaco”) before a stall in the shoulder joint’s azimuth
motor
halted the sequence.

Sol 733: Opportunity continued using the microscopic imager at
Bellemont. Opportunity acquired images from the fourth target
(“Verdun”), but a stall stopped the arm before it could get the last
two
planned images of the Chaco target.

Sol 734: The plan for this sol was to stow the arm, drive about 36
meters (118 feet) to an area known as “Zane Grey,” and unstow the arm.
The arm stalled just before it reached the ready position (before
stowing), and the drive did not occur.

Sol 735 (Feb. 16, 2006): The plan for this sol includes remote sensing
and a short diagnostic activity for the arm.

Total odometry as of sol 735: 6518.87 meters (4.05 miles)