A liquid-helium-cooled, 24-detector grating spectrometer has been developed and used for low-resolving-power astronomical observations in the 5-14-pm spectral range. The instrument has operated on the 91-cm Kuiper Airborne Observatory (KAO), the 3-m IRTF (Mauna Kea), the 3-m Shane telescope (Lick Observatory), and the 152-cm NASA and University of Arizona telescope (Mt. Lemmon, Ariz.). The detectors are discrete Si:Bi photoconductors with indi-vidual metal oxide semiconductor field-effect transistor (MOSFET) preamplifiers operating at 4 K. The system uses a liquid-helium-cooled slit, order-sorter filter, collimator mirror, grating, and camera mirror arranged in a Czerny-Turner configuration, with a cold stop added between the collimator mirror and the grating. The distances between components are chosen so that the collimator mirror images the telescope's secondary mirror onto the cold stop, thus providing a very effective baffle. Scattered radiation is effectively reduced by using liquid-helium-cooled, black baffles to divide the spectrometer into three separate compart-ments. The system noise-equivalent flux density, when used on the 152-cm telescope from 8 to 13 μm with a resolving power of 50, is 4.4 x 10- 17 WCM-2 pm The main appli-cations are for measuring continuum radiation levels and solid-state emission and absorption features in regions of star and planet formation.