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TOPEX/Poseidon: Perspectives on an Ocean Planet

- Spacecraft

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The TOPEX/Poseidon satellite was designed and assembled by Fairchild Space Company, which is now part of Orbital Sciences Corporation. To save development costs, the overall design and configuration of the spacecraft was based on a flight-proven satellite bus also used in the Solar Max and Landsat 4 and 5 projects. The design was modified to incorporate TOPEX/Poseidon-specific instrumentation and to enable it to be launched aboard the Ariane launch vehicle.

Since the Primary Observational Phase of the mission was to be three years, the satellite hardware was designed to survive at least that long in orbit. To achieve the secondary goal of the three-year Extended Observational Phase, the satellite was provided with enough propellant, and good enough batteries and solar arrays, to last more than five years. However, as satellite components degrade, mission operators must come up with different strategies and techniques to maintain satellite health.

As of 1995, the spacecraft was performing better than expected, and should be able to provide global sea level measurements for many years to come.