Thermal Control of Boundaries for JWST Infrared Tests in Cryogenic Vacuum Configuration



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48th International Conference on Environmental Systems


In 2017, the combined optical telescope element and integrated science instrument module (OTIS) of the James Webb Space Telescope (JWST) underwent functional testing and optical metrology verification under cryogenic vacuum conditions in Chamber A at the Johnson Space Center. Testing the infrared science instruments and OTIS optics below 50 K required an environment architecture that comprehensively controlled the temperature and energy path of every seam and penetration in the over 1100 m2 of Chamber A helium shroud surfaces as well as the ground support equipment inside it. This paper outlines the design and implementation of thermal closeouts, thermal anchoring systems for electrical cables, and thermal control systems around room-temperature optical metrology equipment inside the helium shroud. It also details lessons learned from the repeated implementation and testing of these environmental control systems throughout the JWST Pathfinder test campaign.


Jesse Huguet, Harris Corporation
Keith Havey, Harris Corporation
Dwight Cooke, Harris Corporation
Robert Day, Harris Corporation
ICES108: Thermal Control of Cryogenic Instruments and Optical Systems
The 48th International Conference on Environmental Systems was held in Albuquerque, New Mexico, USA on 08 July 2018 through 12 July 2018.


JWST, OTIS, Cryogenic Testing, Vacuum Testing, Optical Testing, Test Boundary Control, Heat Leaks, Stray Light, Thermal Anchoring of Cables, Thermal Closeouts