Spitzer Space Telescope

Description

The Spitzer Space Telescope (formerly SIRTF, the Space Infrared Telescope Facility) is a 0.85-meter telescope with three cryogenically cooled instruments, operating in the 3 - 180 micron range. The observatory is the final element in NASA's Great Observatories Program. The science capabilities include imaging/photometry at 3 - 180 microns, spectroscopy at 5 - 40 microns, and spectrophotometry at 50 - 100 microns. Spitzer will study a wide variety of astronomical phenomena, extending from our Solar System to the distant reaches of the early Universe.

The spacecraft consists of an octagonal bus structure, and a solar array to power the science instruments. The pointing control subsystem employs a celestial-inertial, three-axis stabilized control system. Spitzer has an Earth-trailing Heliocentric orbit.

The Spitzer telescope is a lightweight reflector of Ritchey-Chrétien design. The telescope has an 85 cm diameter aperture. The instruments selected include: 1) a four-channel infrared array camera imaging at 3.6, 4.5, 5.8, and 8 microns. 2) an imaging photometer, with three detector arrays imaging at 24, 70, and 160 microns (one array will also take low-resolution spectra at 50 - 100 microns); 3) a spectrograph providing high- and low-resolution spectroscopy at mid-infrared wavelengths (5 - 40 microns).