Mars Polar Lander Mission Status 1999-10-11

Flight controllers for NASA’s Mars Polar Lander mission have
set October 20 as the date of the next thruster firing that will
fine-tune the spacecraft’s path for its December 3 arrival. The
spacecraft is healthy and operating normally.

On Saturday, October 9, the spacecraft’s fault protection
software placed the lander in a safe standby mode in response to
an errant interaction between attitude control software and the
commands under which the spacecraft was operating at the time.
The flight team successfully returned the spacecraft back to
normal operations within the day.

Extensive analysis of spacecraft data by the flight teams at
NASA’s Jet Propulsion Laboratory in Pasadena, Calif., and
Lockheed Martin Astronautics in Denver, Colo., has confirmed that
the lander does not have the same unit conversion error that
contributed to the loss of the Mars Climate Orbiter last month.

The Mars Polar Lander team has spent the last several weeks
planning the early lander mission that will use the spacecraft’s
radio transmitter to communicate directly with Earth. The team
is also working on a plan to use the currently orbiting Mars
Global Surveyor spacecraft as a communications relay. Project
managers believe all of Polar Lander’s science objectives will be
met.

This week, the team is in the process of testing and
training for the early mission phase on the Martian surface.
Engineers are also re-examining all of the simulations and tests
used to validate the entry, descent and landing phase of the
mission.

Mars Polar Lander is currently 23.6 million kilometers (14.7
million miles) from Mars, approaching the planet at a speed of
4.6 kilometers per second (10,300 miles per hour) relative to the
planet.