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TOPEX/Poseidon: Perspectives on an Ocean Planet

- Navigation

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nav

The Navigation Team is responsible for maintaining the satellite in a pre-determined orbit. As a guide, a near-circular reference orbit has been defined with an altitude of 1336 kilometers and an inclination of 66 degrees. The NAV Team must monitor the spacecraft's orbit, and keep its ground track within 1 kilometer of the reference orbit. To sustain this orbit the Navigation Team makes use of thrusters on board the spacecraft to perform periodic Orbit Maintenance Maneuvers.

Supporting the Navigation Team in their activities is the Flight Dynamics Facility at Goddard Space Flight Center in Maryland. Engineers at this facility perform operational orbit determination for all mission phases using tracking data from NASA's Tracking and Data Relay Satellite System or TDRSS.