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Mars Polar Lander Mission Status

December 10, 1999

Flight controllers for Mars Polar Lander continued their
attempts to communicate with the spacecraft yesterday and
today so that they can be certain they have exhausted all
possibilities before they conclude their search. While a
recovery is still a possibility, the likelihood of hearing
from the lander is considered remote at this point.

Yesterday morning at about 2:45 a.m. PST, the team sent
commands to begin a lengthy “big sweep” during which the
lander uses its steerable medium-gain antenna to scan across
the sky. Presumably, it would eventually scan across the area
where Earth is and its carrier wave signal would be heard by
the Deep Space Network.

Other communication attempts took place today at 3:00 and
6:00 p.m. PST with the 46-meter (about 150-foot) antenna at
Stanford University, Palo Alto, Calif., which listened for a
signal from the lander’s UHF antenna. An earlier attempt by
Stanford that had been scheduled for Tuesday was postponed
when the Stanford antenna experienced mechanical problems.

The “big sweep” will conclude tonight. Engineers will
then begin a process of sending commands to the spacecraft to
switch to back-up hardware and will then repeat some of the
communications attempts they have already tried.

Mission planners are also working to implement a plan to
use Mars Global Surveyor to take pictures of the landing site
for Mars Polar Lander starting sometime next week in hopes of
spotting the spacecraft or parachute.

Review boards will be set up within JPL and at NASA to
study the cause of the apparent loss and explore ways to
prevent a recurrence.

Mars Polar Lander is part of a series of missions in a
long-term program of Mars exploration managed by JPL for
NASA’s Office of Space Science, Washington, D.C. JPL’s
industrial partner is Lockheed Martin Astronautics, Denver.
JPL is a division of the California Institute of Technology,
Pasadena, Calif.