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Mars Polar Lander Mission Status

December 4, 1999

12:10 a.m. PST

Mission controllers for NASA’s Mars Polar Lander and the accompanying Deep Space 2 microprobes will continue attempting to communicate with the lander and the
probes throughout the weekend.

Controllers did not hear from the spacecraft in their first few attempts to communicate with the lander and the probes during the first 12 hours after the scheduled landing

The Deep Space 2 team will try to contact the probes approximately every two hours. The next opportunity for the Mars Polar Lander to contact Earth will be on
Saturday evening, Dec. 4 at about 8:30 p.m. PST.

“We’re remaining upbeat,” said Mars Polar Lander Project Manager Richard Cook at JPL. “We have prepared for various scenarios, and we’re trying all the options.”

Cook pointed out that if the spacecraft entered a standby, or safe mode, about 20 minutes after landing at 12:15 p.m. PST on Fri., Dec. 3, it would not be able to receive
any communications until it takes itself out of safe mode on Saturday evening.

So far, mission controllers have been attempting to communicate with the lander by using its medium gain antenna. If contact has not been established by Sunday
morning., Dec. 5, they will try to communicate with the lander by using NASA’s currently-orbiting Mars Global Surveyor spacecraft as a relay system. In that scenario,
the lander would automatically switch to its UHF radio.

On Fri., Dec. 3, ground controllers attempted to “talk to” the lander at 6:27 p.m. PST. They tried to contact the Deep Space 2 microprobes at 7:30, 9:30 and 11:30 p.m.

The Deep Space 2 microprobes, which impacted Mars about 60 kilometers (about 35 miles) north of the lander, will transmit data through Mars Global Surveyor.

“We know that the Mars Global Surveyor relay system is working,” said Deep Space 2 Project Manager Sarah Gavit.

Latest estimates indicate that Mars Polar Lander touched down on a gentle slope of about two degrees within an “amphitheater” near the edge of a ridge, according to Dr.
David Paige of UCLA, principal investigator for the Mars Volatiles and Climate Surveyor science package on the lander.

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.