Some members of the flight team for NASA’s Mars Exploration Rovers are
preparing for this weekend’s landing of the second rover, Opportunity,
while others are focused on trying to restore the first rover, Spirit,
to working order.

"We should expect we will not be restoring functionality to Spirit for
a significant amount of time — many days, perhaps two weeks — even
in the best of circumstances," said Peter Theisinger, rover project
manager at NASA’s Jet Propulsion Laboratory, Pasadena, Calif.

Spirit transmitted data to Earth today for the first time since early
Wednesday. The information about the rover’s status arrived during
three sessions lasting 10 minutes, 20 minutes and 15 minutes.
Engineers will be examining it overnight and developing a plan for
obtaining more on Saturday morning.

Spirit’s flight software is not functioning normally. It appears to
have rebooted the rover’s computer more than 60 times in the past
three days. A motor that moves a mirror for the rover’s infrared
spectrometer was partway through an operation when the problem arose,
so the possibility of a mechanical problem with that hardware will be
one theory investigated.

"We believe, based on everything we know now, we can sustain the
current state of the spacecraft from a health standpoint for an
indefinite amount of time," Theisinger said. That will give the team
time to work on the problem.

Meanwhile, Spirit’s twin, Opportunity, will reach Mars at 05:05
Universal Time on Jan. 25 (12:05 a.m. Sunday EST or 9:05 p.m. Saturday
PST) at a landing site on the opposite side of the planet from Spirit.
Opportunity’s landing site is on plains called Meridiani Planum
within an Oklahoma-sized outcropping of gray hematite, a mineral that
usually forms in the presence of water. Scientists plan to use the
research instruments on Opportunity to determine whether the gray
hematite layer comes from sediments of a long-gone ocean, from
volcanic deposits altered by hot water, or from other ancient
environmental conditions.

Analysis of Spirit’s descent through Mars’ atmosphere for its landing
at Gusev has contributed to a decision by flight controllers to
program Opportunity to open its parachute higher than had been planned
earlier, said JPL’s Dr. Wayne Lee, chief engineer for development of
the rover’s descent and landing systems.

The Mars Orbiter Camera on NASA’s Mars Global Surveyor orbiter has
taken an image of Spirit’s landing region that shows the spacecraft’s
lander platform on the ground. The jettisoned parachute, backshell
and heat shield are also visible, noted Dr. Michael Malin of Malin
Space Science Systems, San Diego, lead investigator for the orbiter’s
camera and a member of the rover science team.

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

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