James Webb Telescope Begins Cryogenic Testing

NASA's James Webb Space Telescope crossing the threshold into Chamber A at NASA's Johnson Space Center, Houston on June 21, 2017. (Image courtesy of NASA/Chris Gunn.)

We’ve been following the progress of NASA’s James Webb Space Telescope with keen interest for years.

Now, the telescope has been placed in Johnson Space Center's historic Chamber A to prepare for its final three months of testing in a cryogenic vacuum that mimics temperatures in space.

Engineers will perform the test to prove that the telescope can operate in space at these temperatures. Chamber A will simulate an environment where the telescope will experience extreme cold—around 37 Kelvin (-236 C or -393° F).

In space, the telescope must be kept extremely cold, in order to be able to detect the infrared light from very faint, distant objects.

To protect the telescope from external sources of light and heat (like the sun, Earth and moon), as well as from heat emitted by the observatory, a five-layer, tennis court-sized sunshield acts like a parasol that provides shade. The sunshield separates the observatory into a warm, sun-facing side (reaching temperatures close to 185 degrees Fahrenheit) and a cold side (400 degrees below zero). The sunshield blocks sunlight from interfering with the sensitive telescope instruments.

NASA's James Webb Space Telescope sits inside Chamber A at NASA's Johnson Space Center, Houston. (Image courtesy of NASA/Chris Gunn.)

The scientific successor to NASA's Hubble Space Telescope will be the most powerful space telescope ever built. Webb is an international project led by NASA with its partners, the ESA (European Space Agency) and the Canadian Space Agency.

For more news on NASA testing, check out Commercial Supersonic Jet Undergoes NASA Vetting.