Cryogenic Optical Testing of a Fused Quartz Mirror

Abstract

The Space Infrared Telescope Facility (SIRTF) is an orbital, great observatory planned by NASA to enable diffraction-limited astronomical studies in the infrared from 2 μm to 700 μm. The telescope must be cryogenically cooled by Superfluid Helium at 2.5 K to provide the extreme sensitivity required for natural-background-limited observations. Concern about the image quality of the telescope operating at the extremely low temperature led to a cryogenic optics technology program.