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

Mars Polar Lander Mission Status
November 30, 1999

       Flight controllers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., report that the Mars Polar Lander spacecraft is in excellent health as it prepares for its arrival at the red planet on Friday.

       This morning at about 10 a.m. Pacific time, the spacecraft performed a fourth scheduled maneuver to adjust its flight path. The lander fired its small thrusters for 12.6 seconds to adjust its speed by about 0.6 meters per second (about 1 mile per hour). The lander is currently traveling at a speed of 19,300 kilometers per hour (12,000 miles per hour).

       "The current estimates show that we are right on target," said Dr. Sam Thurman, flight operations manager for the lander at JPL. "The navigation team says we are very close to the target point for atmospheric entry on Friday. A large team has been working since Thanksgiving, doing everything that's necessary to get us on the proper flight path for a good entry position."

       When the spacecraft arrives at Mars, it must enter the atmosphere through a corridor that is 10 kilometers (6 miles) wide and 40 kilometers (25 miles) long and begins about 125 kilometers (78 miles) above the surface.

       Early Friday morning, the team will evaluate whether they need to perform an additional maneuver to fine-tune the landing. If needed, this final maneuver would take place on December 3, at 5:30 a.m. Pacific time, about six hours prior to entry into the Martian atmosphere.

       Later today, the flight team will start the master sequence on the spacecraft that begins the countdown for the entry, decent, and landing activities. The lander is currently 3.5 million kilometers (about 2 million miles) from Mars, and is scheduled to land on Friday, December 3, shortly after noon Pacific time.

       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, Colo. JPL is a division of the California Institute of Technology, Pasadena, Calif.

#####