The James Webb Space Telescope's Golden Spider
Posted on August 23, 2012
NASA's Goddard Space Flight Center shared this photograph today of an object that looks like a massive golden spider intermixed with wires and cables. The photo is ground support equipment, including the Optical Telescope Simulator (OSIM), for the James Webb Space Telescope. You can see a larger version of the image here.
The photo was taken from inside a large thermal-vacuum chamber, called the Space Environment Simulator (SES), at NASA's Goddard Space Flight Center in Greenbelt, Md. The OSIM has been blanketed with special insulating material to help control its temperature while it goes into the deep freeze testing that mimics the chill of space that Webb will ultimately experience in its operational orbit over 1 million miles from Earth. These gold thermal blankets are made of aluminized kapton, a polymer film that remains stable over a wide range of temperatures.
NASA says that during testing, OSIM's temperature will drop to 100 Kelvin (-280 F or -173 C) as liquid nitrogen flows through tubes welded to the chamber walls and through tubes along the silver panels surrounding OSIM's optics. These cold panels will keep the OSIM optics very cold, but the parts covered by the aluminized kapton blankets will stay warm.