The installation of equipment into the James Webb Space Telescope requires patience and precision. To prepare for the installation of the actual flight equipment and ensure perfection in the installations, scientists need to practice with an identical test unit. Scientists at NASA's Goddard Space Flight Center in Greenbelt, Md. are currently rehearsing with the placement of the Webb's Microshutter Array into the NIRSpec.
ETUs, or engineering test units, are simulations of equipment that will fly on the Webb telescope. Back in 2010, NASA Goddard received the ETU of the Webb telescope's Near-Infrared Spectrograph (NIRSpec) instrument from its manufacturer in Germany. Currently, engineers and scientists are preparing and installing the Microshutter Array simulator into the engineering test unit of the Webb telescope's Near-Infrared Spectrograph (NIRSpec) instrument.
NIRSpec will be the principal spectrographic instrument aboard the Webb telescope. The NIRSpec's components will be sensitive to infrared light from a variety of astronomical objects -- from the most distant galaxies in the universe to relatively nearby exoplanets within our Milky Way galaxy. NIRSpec will be capable of obtaining spectra of more than 100 objects in the cosmos simultaneously. Studying an object's spectrum will help scientists determine distinct physical properties of the object, such as distance, age, and even chemical composition. These measurements are important in unraveling the history of galaxy and planet formation.
Also: Learn about the UltraViolet Spectograph.