JPL: Mars Orbiter/Take 2

Brian D Williams (talon57@well.com)
Tue, 12 Oct 1999 07:08:26 -0700 (PDT)

MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIFORNIA 91109. TELEPHONE (818) 354-5011 http://www.jpl.nasa.gov

               Mars Polar Lander Mission Status
                       October 11, 1999

     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.

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