James Webb Space Telescope
Overview
The James Webb Space Telescope (JWST) is an orbiting observatory that will take the place of the Hubble Space Telescope. Using infrared astronomy, it observes distant galaxies, star formations and exoplanet atmospheres.RAL Space involvement
RAL Space was responsible for overall instrument thermal design and analysis and production of the thermal hardware for the Mid-Infrared Instrument (MIRI). We also completed assembly, integration, testing & verification of instrument including provision of necessary bespoke test facilities; initial calibration; consortium contamination control leadership role. Following launch, scientists and engineers from RAL Space and the UK ATC were fundamental in MIRI’s commissioning phase and ensuring that the instrument operated as expected.
An illustration of the James Webb Space Telescope. Image: NASA, ESA, CSA, Northrop Grumman
Keeping MIRI's thermal systems cool
Due to the need to operate at mid-infrared wavelengths, MIRI needed to be cooled to a temperature of around 6K, much lower than the rest of the instruments on JWST. To reach this temperature, MIRI needed to be was actively cooled by a cryogenic refrigerator, or cryocooler. The cryocooler was specially developed by NASA’s Jet Propulsion Laboratory while the RAL Space were responsible for overall instrument thermal engineering. Our thermal engineers needed to developed a design that minimised heat transfer between the cooler and the rest of the JWST, preventing too much heat transfer from the rest of JWST so that the cooler was not overloaded and the required temperature was maintained.
