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Mars Polar Lander Mission Status
December 3, 1999, 5 p.m.

Mission controllers for NASA’s Mars Polar Lander mission are awaiting the next opportunity to communicate with the spacecraft, whose transmissions have not yet been received since it landed on Mars shortly after noon Pacific time today.

“I’m very confident the lander survived the descent,” said Mars Polar Lander Project Manager Richard Cook at JPL. “Everything looked very good. I think we’re a long way from getting concerned. It is not unexpected that we would not hear from it during the first opportunity.” A variety of hardware problems from which the lander could recover may be responsible for the delay in initial telecommunications.

During the last telecommunications opportunity, which began at 2:04 p.m. PST, the spacecraft would have automatically moved its steerable antenna in a search pattern designed to find the Earth. The next communications window opens at 6:27 p.m. PST today when the team will again send commands to the lander instructing it to maneuver its medium gain antenna in another attempt to look for Earth. The lander would then carry out that procedure to transmit to Earth beginning at 8:08 p.m. until 10:40 p.m. tonight.

Even if no transmissions are heard today mission controllers have another opportunity to hear from the lander on Saturday. This is the time the spacecraft would be transmitting if it went into a safe mode shortly after landing. Engineers would also listen for it on Sunday evening, when the spacecraft would automatically switch to its UHF radio and transmit via Mars Global Surveyor. After that, they will send commands instructing the spacecraft to swap between various hardware subsystems in case one is damaged.

The Deep Space 2 microprobes, which impacted Mars about 60 kilometers (about 35 miles) from the lander, will transmit data through Mars Global Surveyor. The team will be listening tonight at about 7:30 p.m. when contact is expected with the microprobes.

The flight team’s best flight path estimates are that lander most likely touched down at about 76.1 degrees south latitude, 195.3 degrees west longitude. The estimates for the Deep Space 2 microprobe impacts are 75.0 degrees south latitude, 163.5 degrees east longitude with the two probes being separated from each other by only a few kilometers.

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 in Pasadena.