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New Space Support Equipment (SSE) components developed for the Hubble Space Telescope Second Servicing Mission are described, with particular emphasis on how flight experience from the 1993 First Servicing Mission was utilized in the design and testing process. The new components include the Second Axial Carrier (SAC) Axial Scientific Instrument Protective Enclosure (ASIPE), the magnetic-damped SAC ASIPE Load Isolation System, the Enhanced Power Distribution and Switching Unit (EPDSU), and the Multi-Mission Orbital Replacement Unit Protective Enclosure (MOPE). Analytical modeling predictions are compared with on-orbit data from the Hubble Space Telescope (HST) Second Servicing Mission. Those involved in thermal designs of hardware for use on the Shuttle or Space Station, particularly with astronaut interaction, may find interest in this paper.

During the First Servicing Mission for the Hubble Space Telescope, two replacement instruments and several spacecraft components were installed successfully. Most of the replacement hardware was carried up in protective enclosures that provided thermal control over a wide range of potential mission attitudes. Some items added late to the mission were protected by passive thermal systems and attitude constraints on the Shuttle. This paper focuses on thermal design challenges presented by the replacement hardware, enclosures, and carriers, and includes an assessment of flight thermal performance.

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.

A large telescope aperture, stringent thermal stability and temperature range requirements, and a passively-cooled 150°K module presented major challenges in thermal design and hardware fabrication of this Small Explorer science instrument. This paper details SWAS thermal system design, problems that were revealed in thermal testing, and the hardware changes that brought the design into an acceptable condition. Thermal test techniques that helped verify design adequacy are described, as well as the analytical methods used to correlate the thermal model and predict flight performance.

Substantial damage to the outer layer of Hubble Space Telescope (HST) thermal blankets was observed during the February 1997 servicing mission. After six years in low-earth orbit, many areas of the aluminized Teflon® outer blanket layer had significant cracks, and some material was peeled away to expose inner layers to solar flux. After the mission, the failure mechanism was determined, and repair materials and priorities were selected for follow-on missions. This paper focuses on the thermal design of the repair hardware and the creative solutions developed to meet thermal, mechanical, and EVA requirements. Hardware development, training, and on-orbit activities are also discussed.

A large telescope aperture, stringent thermal stability and temperature range requirements, and a passively-cooled 150°K module presented major challenges in thermal design and hardware fabrication of this Small Explorer satellite. This paper reviews briefly the thermal design of the SWAS science instrument, and examines the first three months of on-orbit thermal history. Measured temperatures for both the science payload and the spacecraft module and solar arrays are compared with those predicted by the correlated analytical model. Similarities and differences are interpreted in terms of the major uncertainties remaining after thermal-balance testing, especially those of MLI performance and telescope aperture properties. Review of the thermal model adequacy and thermal design verification are included to suggest improvements in the thermal design process for future missions.