JWST OTIS Cryogenic Vacuum Test, Part 1: Thermal Architecture

This series discusses the cryogenic vacuum testing of the James Webb Space Telescope’s Optical Telescope Element and Integrated Science Instrument Module, or OTIS. This test required multiple years of planning and was executed from July-October of 2017 at NASA’s Johnson Space Center in Houston. There are four parts to this series: Part I will introduce the major components of James Webb and specifically the thermal architecture of the OTIS cryogenic vacuum or CV test. Part II will encompass the extensive thermal analysis performed to prepare for the test. Part III will talk about the preparations for off-nominal events: what analysis was done, and how steps were taken pre-test to anticipate unexpected circumstances and mitigate their impacts to hardware and test timeline. Part IV is a recap of the lessons learned from the thermal test conductor perspective for both the payload team and the ground support equipment or GSE team.