Each of NASA’s two Mars Exploration Rovers is using its versatile
robotic arm for positioning tools at selected targets on the red

Also, a newly completed 360-degree color panorama from Opportunity
shows a trail of bounce marks coming down the inner slope of the small
crater where the spacecraft came to rest when it landed on Mars nine
days ago.

Opportunity extended its arm early today for the first time since
pre-launch testing. “This was a great confirmation for the team,”
said Joe Melko of NASA’s Jet Propulsion Laboratory, Pasadena, Calif.
Melko is mechanical systems engineer for the arm, which is also called
the instrument deployment device.

Mission controllers at JPL are telling Opportunity to use two of the
instruments on the arm overnight tonight to examine a patch of soil in
front of the rover. A microscope on the arm will reveal structures as
thin as a human hair and a Moessbauer Spectrometer will collect
information to identify minerals in the soil, according to plans.
Tomorrow, the rover will be told to turn the turret at the end of the
arm in order to examine the same patch of soil with another
instrument, the alpha particle X-ray spectrometer, which reveals the
chemical elements in a target.

Spirit is now in good working order after more than a week of
computer-memory problems. It is brushing dust off of a rock today with
the rock abrasion tool on its robotic arm. After the brushing, Spirit
will use the microscope and two spectrometers on the arm to examine
the rock.

“We’re moving forward with our science on the rock Adirondack,” said
JPL’s Jennifer Trosper, Spirit mission manager. Reformatting of
Spirit’s flash memory was postponed from today to tomorrow. The
reformatting is a precautionary measure against recurrence of the
problem that prevented Spirit from doing much science last week.

Later in the week, Spirit will grind the surface off of a sample area
on Adirondack with the rock abrasion tool to inspect the rock’s
interior. After observations of Adirondack are completed, the rover
will begin rolling again. “We are already strategizing how to drive
far and fast,” Trosper said.

Observations by each rover’s panoramic camera help scientists choose
where to drive and what to examine with the instruments on each
rover’s arm. Dr. Jeff Johnson, a rover science team member from the
U.S. Geological Survey’s Astrogeology Team, Flagstaff, Ariz., said
that 14 filters available on each rover’s panoramic camera allow the
instrument to provide much more information for identifying different
types of rocks than can be gleaned from color images such as the new
panoramic view.

“By looking at the brightness values in each of these wavelengths, we
can start to get an idea of the things we’re interested in, especially
to unravel the geological history of these landing sites,” Johnson

The main task for both rovers in coming weeks and months is to find
clues in rocks and soil about past environmental conditions,
particularly about whether the landing areas were ever watery and
possibly suitable for sustaining life.

Each martian day, or “sol” lasts about 40 minutes longer than an Earth
day. Spirit begins its 31st sol on Mars at 1:23 a.m. Tuesday, Pacific
Standard Time. Opportunity begins its 11th sol on Mars at 1:44 p.m.
Tuesday, PST. The two rovers are halfway around Mars from each other.
JPL, a division of the California Institute of Technology in Pasadena,
manages the Mars Exploration Rover project for NASA’s Office of Space
Science, Washington, D.C.