Temperature control

Orion with European Service Module

Space is a harsh place: temperatures can vary quickly depending on whether spacecraft are in direct view of the Sun or flying in the shade of a planet. The Orion spacecraft must control its temperature to keep the astronauts comfortable and its equipment operating. 

Electronics and other systems produce heat of their own that needs to be expelled to avoid overheating. Coolant is pumped around a closed loop that includes six radiators near the spacecraft’s exterior, much like in a car engine.

Electrical heaters keep the spacecraft warm when needed. In addition, the European Service Module is covered in multiple layers of space insulation. The insulation also blocks the heat from the thrusters.

Technical details

  • Active system
    • Collects thermal loads from the whole Orion spacecraft
    • Radiators reject heat (4 full-length, 2 split)
    • Two fully independent loops work simultaneously for safety
    • Cold plates cool the equipment
    • A fluid pump package circulates the coolant fluid
    • Coolant fluid Is HFE-7200 (HydroFluoroEther)
  • Passive system
    • Heaters (thermistors and wire heater)
    • Insulation: Multiple Layer Insulation thermal blankets; high-temperature Multiple Layer Insulation blankets for thruster and engine nozzle thermal protection

Last update: 30 November 2015

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