Design alternatives for the Shuttle Infrared Telescope Facility
The paper discusses the Shuttle Infrared Telescope Facility (SIRTF), a versatile astronomical telescope that can accomodate photometric, spectroscopic, and polarimetric measurements. It is expected to be 100 to 1000 times more sensitive than any existing infrared telescope; detailed designs of cooled IR telescopes were made for the Infrared Astronomical Satellite and the Small Helium Cooled Infrared Telescope for Spacelab 2. Rocket tests verified the capability of using superfluid helium as a cryogen in zero gravity. Constraints on funds for Shuttle payloads require an evolutionary approach to the development of the full potential of SIRTF, necessitating consideration of design alternatives involving the optical configuration, the cryogen, the mechanical structure, and size of SIRTF.