HAWC - A far-infrared camera for SOFIA

Many IR sources are dusty; embedded stars are obscured, often completely, and their light is absorbed. The starlight heats the dust, typically to temperatures of tens or hundreds of Kelvin, and the heated dust radiates in the far IR, at wavelengths for which the Stratospheric Observatory for IR Astronomy (SOFIA) is optimized. These dusty targets radiate most or all of their energy in the far IR: broadband imaging with the highest possible spatial resolution is the natural starting point form which to develop an understanding of their morphology and energetics. Because SOFIA is the largest far IR telescope, it delivers the best spatial resolution. The wealth of detail revealed when resolution improves often result in startling insights, as new pictures of old favorites from the Hubble Space Telescope so regularly remind us. We therefore believe that most SOFIA studies will begin with high spatial resolution broadband imaging, and that a facility science instrument is required to serve this heavy and continuing workload.