Relax: James Webb Space Telescope in Camera A
James Webb Space Telescope (JWST) has completed its final round of cryogenic testing in Space Johnson of the NASA Center in Houston, Texas. On July 10, the optical telescope and the integrated module of the ship's scientific instruments were sealed in Chamber A, which is a huge cylindrical vacuum chamber 27 m in height and 17 m in diameter. There, it cooled to temperatures as low as 11K, using cold helium gas and then underwent a three-month test program to ensure that the JWST operates in a cold, airless environment similar to space.
One of the tests consisted of ensuring that the telescopes 18 primary mirror segments covered with gold continue to act as a single mirror when cooled. The engineers also made sure that the optics of the telescope and the instrument module can work together under extreme conditions.
Cape the Storm
Before testing began, one week pbaded to remove most of the air from the chamber and one month to cool the instruments to the temperature required for the test. The testing program coincided with Hurricane Harvey, which dropped more than a meter of rain in parts of Houston. Despite the difficult conditions during the storm, the team managed to safeguard that the tests were not interrupted.
The instrument module and optics will now be shipped to Northrop Grumman Aerospace Systems in Los Angeles, where they will be integrated into the JWST spacecraft. Once this is complete, the spacecraft will be subject to a final round of "observatory-level testing" before it is launched in the spring of 2019.
The JWST program is led by NASA and involves the Agency European Space and Canadian Space Agency.