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27 June 2017

NASA’s Webb Telescope Placed in Deep-freeze Vacuum for Final Round of Testing

Technology designed for a life in the bitter-cold vacuum of space has to endure some truly testing conditions, from high levels of radiation to temperatures well below freezing (unless the equipment happens to find itself under the gaze of a nearby star, in which case heat may be the bigger problem). To this end, NASA recently relocated the James Webb Space Telescope to a facility at the Johnson Space Center where it was subsequently placed in the historic ‘Chamber A’, a cryogenic vacuum chamber which will mimic the conditions of space in order to ascertain how well the telescope performs over the duration of 3 months.

Img: NASA/Chris Gunn
The telescope was placed in the chamber on June 20th 2017, and will remain there for 3 months at temperatures of around 37 Kelvin (-236°C/-393°F) – the approximate temperature of the vast majority of space.

The reason for this rigorous testing is the fact that the infrared sensors upon which the telescope relies must be kept extremely cold in order to properly function, so insulating the craft against the cold temperatures of space is not a feasible option; instead it must be crafted in such a way that the extreme cold causes no harm to other sensitive components.

Cold however is not the only issue the telescope must face; heat too may cause an issue if not properly prepared for. That may sound contradictory, but as cold as space may be, stars deal out some serious levels of heat. To protect the telescope from such external sources of heat it has been fitted with a five-layer, tennis court-sized sunshield, shading the telescope and its components to some degree. This sunshield effectively separates the telescope into halves; one side facing the sun and experiencing temperatures of around 185°F, and one side enduring the full brunt of the cold vacuum of space, with temperatures nearing -400°F.

Once testing is complete and the telescope is put into service, it will officially be the most powerful space telescope ever built. This comes as little surprise, as the telescope has been described as the scientific successor to the Hubble Space Telescope upon which countless studies have relied over the years.


Sam Bonson

Sam is an aspiring novelist with a passion for fantasy and crime thrillers. He is currently working as a content writer, journalist & editor in an attempt to expand his horizons.