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TOPEX/Poseidon: Perspectives on an Ocean Planet

- Instrument Module

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im

The TOPEX/Poseidon Instrument Module (IM) is comprised of all the scientific sensors and systems that provide the spacecraft with its mission-specific data collection, communication, and solar power gathering capabilities.

The IM is a large aluminum box which attaches to the MMS. Since many of the instruments within the IM operate best within a controlled temperature range, thermal control louvers in the IM walls open and close to maintain the desired temperature as the sun shines on the spacecraft from different directions.