NASA’s Spirit rover has successfully driven to its first target on
Mars, a football-sized rock that scientists have dubbed Adirondack.

The Mars Exploration Rover flight team at NASA’s Jet Propulsion
Laboratory, Pasadena, Calif., plans to send commands to Spirit early
Tuesday to examine Adirondack with a microscope and two instruments
that reveal the composition of rocks, said JPL’s Dr. Mark Adler,
Spirit mission manager. The instruments are the Mössbauer
spectrometer and the alpha particle X-ray spectrometer.

Spirit successfully rolled off the lander and onto the martian
surface last Thursday. To make the drive to Adirondack, the rover
turned 40 degrees in short arcs totaling 95 centimeters (3.1 feet).
It then turned in place to face the target rock and drove four short
moves straightforward totaling 1.9 meters (6.2 feet). The moves
covered a span of 30 minutes on Sunday, though most of that was
sitting still and taking pictures between moves. The total amount
of time when Spirit was actually moving was about two minutes.

“These are the sorts of baby steps we’re taking,” said JPL’s Dr.
Eddie Tunstel, rover mobility engineer.

“The drive was designed for two purposes, one of which was to get to
the rock,” Tunstel said. “From the mobility engineers’ standpoint,
this drive was geared to testing out how we do drives on this new
surface.” Gathering new information such as how much the wheels
slip in the martian soil will give the team confidence for more
ambitious drives in future weeks and months.

“Adirondack is now about one foot (30 centimeters) in front of the
front wheels,” he said.

Scientists chose Adirondack to be Spirit’s first target rock rather
than another rock, called Sashimi, that would have been a shorter,
straight-ahead drive. Rocks are time capsules containing evidence of
the environmental conditions of the past, said Dr. Dave Des Marais,
a rover science-team member from NASA Ames Research Center, Moffett
Field, Calif. “We needed to decide which of these time capsules to

Sashimi appears dustier than Adirondack. The dust layer could
obscure good observations of the rock’s surface, which may give
information about chemical changes and other weathering from
environmental conditions affecting the rock since its surface was
fresh. Also, Sashimi is more pitted than Adirondack. That makes it a
poorer candidate for the rover’s rock abrasion tool, which scrapes
away a rock’s surface for a view of the interior evidence about
environmental conditions when the rock first formed. Adirondack has
a “nice, flat surface” well suited to trying out the rover’s tools
on their first martian rock, Des Marais said.

“The hypothesis is that this is a volcanic rock, but we’ll test that
hypothesis,” he said.

Spirit arrived at Mars Jan. 3 (EST and PST; Jan.
4 Universal Time) after a seven-month journey. In coming weeks and months,
according to plans, it will be exploring for clues in rocks and
soil to decipher whether the past environment in Gusev Crater
was ever watery and possibly suitable to sustain life.

Spirit’s twin Mars Exploration Rover, Opportunity, will reach Mars
on Jan. 25 (EST and Universal Time; 9:05 p.m., Jan. 24, PST) to
begin a similar examination of a site on the opposite side of the
planet from Gusev Crater.

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. Images and additional
information about the project are available from JPL at

from Cornell University, Ithaca, N.Y., at .