Mission Profile
The 14 day launch window for the Mars Climate Orbiter begins on 10 December 1998. The Delta 7425 3rd stage will put the spacecraft into trans-Mars trajectory and about 15 days after launch the largest trajectory correction maneuver (TCM) is executed using the hydrazine thrusters. During cruise to Mars up to 3 more TCM's may be required. The spacecraft will reach Mars and execute a 16 to 17 minute orbit insertion main engine burn on 23 September 1999. The burn will slow the spacecraft from a speed of 5.9 km/s (relative to Mars) to about 4.7 km/s and put it into a 29 hour elliptical (160 x 39,000 km) polar capture orbit. The orbiter will immediately begin aerobraking, using the solar panel to provide resistance. Aerobraking will continue until a 90 x 405 km orbit is achieved, nominally on 22 November 1999. The hydrazine thrusters will be used to change the orbit to a 405 km near-circular polar science mapping orbit on 1 December 1999. The orbit will be nearly Sun-synchronous, with a descending node of about 4 p.m. local time.
The first phase of the mission is to support the Mars Polar Lander from its landing on Mars on 3 December 1999 to the end of the lander primary mission on 29 February 2000. The orbiter will pass over the lander site 10 times per martian day for 5-6 minutes each time, communicating via the UHF 2-way relay link at 128 kbits/s. Mars science operations and mapping, involving operation of the MARCI and PMIRR, will initiate on 3 March 2000 and continue for one martian year (687 days). At the end of the mapping mission on 15 January 2002, the orbiter will be placed in a stable orbit and function as a UHF relay for the Mars 2001 mission which arrives at Mars at this time.
The Mars Surveyor '98 program development costs are capped at 183.9 million dollars. The Mars Climate Orbiter is part of NASA's 10-year Mars Surveyor Program, which will feature launches every 26 months when the Earth and Mars are favorably aligned.