We are constructing a facility-class, mid/far-infrared camera for the Stratospheric Observatory for Infrared Astronomy (SOFIA). The Faint Object infraRed CAmera for the Sofia Telescope (FORCAST) is a two-channel camera with selectable filters for continuum imaging in the 5-8, 17-25 micron, and/or 25-40 micron regions. The design supports simultaneous imaging in the two-channels. Using the latest 256x256 Si:As and Si:Sb blocked-impurity-band detector array technology to provide high-sensitivity wide-field imaging, FORCAST will sample images at 0.75 arcsec/pixel and have a 3.2'x3.2' instantaneous field-of-view Imaging is diffraction limited for lambda > 15 microns. Since FORCAST operates in the wavelength range where the seeing from SOFIA is best, it will provide the highest spatial resolution possible with SOFIA. FORCAST may eventually support a spectroscopy mode (resolving power, R similar to 300 and R similar to 1000-2000) using silicon grisms mounted in the filter wheels. The science projects planned by the investigator team include multicolor imaging of the galactic center, Vega-like dust clouds, and star formation regions in normal spiral galaxies and active galaxies. This instrument will be of great value to the SOFIA community for imaging of protostellar environments, young star clusters, molecular clouds, and galaxies. Multicolor information allows determination of dust temperatures, dust optical depths (and dust masses), dust composition, location of ionizing sources, and the spatial morphology of star forming regions. Low and medium resolution spectroscopy will provide information about chemical composition, and temperatures in a wide variety of Galactic and extra galactic sources.
