Newly modified cryogenic optical test facility at Marshall Space Flight Center

Abstract

NASA Marshall Space Flight Center has maintained and operated a world-class x-ray optics and detector testing facility known as the X-ray Calibration Facility (XRCF) since the mid 1970's. The ground testing and calibration of the Chandra X-ray Observatory optics and detectors were successfully completed at the XRCF in 1997. In 1999, the facility was upgraded in preparation for cryogenic testing of lightweight telescope mirrors without compromising the existing x-ray testing capability. A gaseous Helium cooled enclosure or shroud capable of 20 degrees Kelvin and vibration isolated instrumentation mount were added to the existing facility. A precision remote-control five-axis motion mirror support was modified to operate under cryogenic conditions. Mirrors with diameters as large as two meters, and radii of curvature up to twenty meters can be accommodated in the He shroud.