MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011
December 5, 1999
Another telecommunications strategy to hear from NASA’s Mars Polar
Lander produced no results today, but the mission flight team is proceeding
through its contingency checklist in continuing attempts to communicate with
the spacecraft.
From about 11 to 11:30 a.m. PST today, the team listened for but
detected no signals from the lander’s UHF transmitter, which would have been
relayed through the already-orbiting Mars Global Surveyor spacecraft. This
was the first attempt at using the Global Surveyor; until then, engineers
had tried to use the lander’s medium gain antenna to transmit directly to
Earth.
“We continue to work through our plan, which gives us confidence that
we haven’t exhausted all the possibilities,” said Mars Polar Lander Project
Manager Richard Cook. “But clearly, the team is getting more frustrated” as
attempts to reach the lander yield no results.
No contact has yet been made in continuing efforts to communicate
with the two Deep Space 2 Mars microprobes that also impacted Mars about 60
kilometers (abut 35 miles) north of the lander on Dec. 3, said Deep Space 2
Project Manager Sarah Gavit. Mission engineers believe the probes have
entered a phase where they broadcast their data automatically for one minute
out of every five.
Gavit said that data from last night’s try at hearing signals from
the probes that could have been recorded on NASA’s Mars Global Surveyor
orbiter would be reviewed later today. The team will also look for
microprobe signals that could be relayed by Global Surveyor during another
transmission today, she said. “If we haven’t heard from them in the next 24
hours (by about noon Monday PST), we will have exhausted our opportunities
to hear from them.”
Tonight, Sunday, Dec. 5 from 10:10 to 11:10 p.m., an attempt will be
made to listen for signals from the lander that would be sent through its
medium gain antenna if the lander is in safe, or standby mode, and its
antenna is not pointed correctly.
On Tuesday, Dec. 7, at 12:20 a.m. PST, attempts to hear signals from
the lander’s UHF transmitter will be made again using Mars Global Surveyor.
This attempt would detect signals if Polar Lander is in safe mode. After
Tuesday’s post-midnight attempt, Cook said, “I think we will be at the point
of diminishing returns in terms of getting in contact with 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.
