Environmental testing for the cryogenic harness on the James Webb Space Telescope (JWST)
21 Oct 2008



Environmental Testing for the Cryogenic Harness on the James Webb Space Telescope (JWST)

Artist's impression of the Webb Telescope.

The STFC Space Science and Technology Department (SSTD) have been awarded a £800,000 contract to carry out environmental testing on a cryogenic harness for the James Webb Space Telescope (JWST) - which will succeed the Hubble Space Telescope and explore the formation of the first stars and galaxies by looking at light from the early Universe. The telescope is a massive international collaboration between the European Space Agency (ESA), NASA and the Canadian Space Agency (CSA).

The harness - the spacecraft's central nervous system - will link the spacecraft systems to the telescope, controlling its alignment and providing temperature information for health monitoring. The test programme will be carried out at SSTD at the STFC Rutherford Appleton Laboratory (RAL) in Oxfordshire during 2009.

The contract was awarded by the Staffordshire based company Tekdata Interconnect Systems who are manufacturing the harness for Northrop Grumman, the company developing the JWST.

The JWST will be placed in an orbit 1.5 million kilometres from Earth where the 6.5 metre telescope will be cooled to a cold, stable temperature of 25 Kelvin (minus 248 degrees Celcius). This will enable observations to be made of the first faint glows as stars and galaxies began to form after the Big Bang and give us more information about the evolution of our own solar system.

Using the Assembly, Integration and Verification Facility (AIV) at RAL, the harness will be put through vibration testing to ensure it will survive the violence of a rocket launch and thermal testing in which the harness is placed in a vacuum chamber and cycled through the extremes of temperature it will encounter both during launch and in its final orbit. By testing to slightly more extreme conditions than expected, SSTD will ensure that the harness will function correctly once in space.

Eric Sawyer from SSTD said "This is a great opportunity for SSTD to work with UK industry on the most ambitious scientific space mission for decades through utilising our high technology test facilities".

Scientists from STFC are already involved with the JWST mission and are part of the international team developing the Mid Infra-Red Instrument (MIRI) for the JWST. The verification model for MIRI was built and tested in a specially adapted test facility at RAL, while work to build the flight model spectrometer pre-optics at STFC's UK Astronomy Technology Centre is now underway.

The AIV test facilities at RAL consist of a vibration test facility, with the capability of cryogenic vibration, numerous thermal vacuum facilities, vacuum bakeout facilities and large clean rooms for assembly and integration of sensitive flight hardware. They are all equipped with the latest instrumentation, and have modern computer-based acquisition systems.

I am delighted to hear that Tekdata and RAL have won this contract with Northrop Grumman. I am sure the excellent track record of the STFC funded UK MIRI team has helped demonstrate that SSTD is the best place for this work", said Gillian Wright of the UK-ATC, the JWST MIRI European Principal Investigator. "It is reassuring to know that the testing of these harnesses on which our science ultimately depends is in such safe hands", she added.

For more information please contact: RAL Space Enquiries