Thermal Design and Performance of the Axial Scientific Instrument Protective Enclosure (ASIPE) for Hubble Space Telescope On-Orbit Servicing

Thermal design and verification testing of the ASIPE, one element of the re-usable Space Support Equipment (SSE), are discussed with respect to how unique and competing requirements are satisfied for Scientific Instrument (SI) conditioning, safety, and on-orbit servicing operations. A system approach, rather than optimizing any one performance characteristic, results in a robust design. The special thermal testing required to verify the unique enclosure is described. Analytical modeling predictions are compared with on-orbit telemetry from the Hubble Space Telescope (HST) First Servicing Mission (FSM). Emphasis is on why the design works well, rather than the specific hardware selected. Those involved in thermal designs of hardware with astronaut interaction may find interest in this paper.