James Webb Space Telescope (JWST) thermal shield testing. NASA engineer checking out copper test wires inside the thermal shield of the Mid-Infrared Instrument (MIRI) of the JWST. The shield is designed to protect the vital MIRI instrument from excess heat. This testing is taking place in a thermal vacuum chamber. The JWST is an infrared telescope that is scheduled to be launched in 2021. By using infrared wavelengths, the JWST will be able to see through much of the dust that obscures visible light. It will also study dark matter, thought to form the majority of the matter in the universe. Photographed on 8 December 2017, at NASA's Goddard Space Flight Center in Greenbelt, Maryland, USA.