Mars Polar Lander Launched1/03/1999 20:21:10 UTC (15:21:10 EST)
The Mars Polar Lander spacecraft launched January 3, 1999 at 20:21:10
UTC (15:21:10 EST) from the Cape Canaveral Air Force Station (CCAFS)
Space Launch Complex 17 (SLC-17) on the 1st day of its 25 day launch
window. The second pad at SLC-17 was used for the lander launch to
enable the quick two week turnaround from the end of the orbiter
launch period. The lander will enter the Martian atmosphere directly
from the hyperbolic transfer orbit at 7 km/s in Deccember 1999. The
lander spacecraft will decelerate to a soft landing using a heat
shield to aerobrake, a parachute, and actively guided propulsion to
reduce vertical velocity to less than 2.4 m/s and horizontal velocity
to less than 1 m/s at surface touchdown. The lander will be targeted
to the northernmost boundary of the polar layered deposits at a high
southern latitude site, between 75 degrees and 80 degrees south
latitude. The surface science mission will be conducted over the
course of a 3 month primary mission. The landing will occur during
late spring in the southern hemisphere and extend through the early
summer season. The timing of the landing is optimal for a high
southern latitude site because the sun is always above the horizon
during the course of the primary mission providing maximum solar
insolation and a relatively benign thermal environment. 
