Instrument Information
IDENTIFIER urn:nasa:pds:context:instrument:clem1.lwir::1.2
NAME Long Wavelength Infrared Camera for CLEM1
TYPE Imager
DESCRIPTION The Longwave Infrared Camera (LWIR) is designed with a catadioptric lens and a 128 x 128 mercury cadmium telluride focal plane array (FPA), operating at cryogenic temperatures around 65 K. It provides thermal observations of the lunar surface in the 8.0 to 9.5-micron spectral range, but has limited overlapping coverage due to its narrow field of view.For proper calibration, the LWIR camera converts digitized signals into radiance measurements. The sensitivity of the FPA varies across its field of view, affected by temperature stability after the cryocooler's cooling period. Calibration was conducted pre-launch and during operations, particularly over the Apollo 17 landing site.The camera operates in three modes: selectable image integration times, gain mode with 32 settings, and offset mode with 256 settings. Key specifications include an 8-bit A/D resolution, a frame rate of 52.9 Hz, and a 1-degree field of view. The camera has no filter wheel and is tailored for a specific spectral band.The LWIR camera weighs 2100 grams and is 14.7 cm in diameter and 36.1 cm long, powered by a cryocooler that maintains temperature control of the FPA.
MODEL IDENTIFIER
NAIF INSTRUMENT IDENTIFIER
SERIAL NUMBER not applicable
REFERENCES Lawson, S.L., B.M. Jakosky, H.-S. Park, and M.T. Mellon, Brightness temperatures of the lunar surface: Calibration and global analysis of the Clementine long-wave infrared camera data, J. Geophys. Res., 105, 4273-4290, 2000.

Priest, R.E., I.T. Lewis, N.R. Sewall, H. Park, M.J. Shannon, A.G. Ledebuhr, L.D. Pleasance, M.A. Massie, and K. Metschuleit, Clementine Longwave Infrared Camera, Proceedings of the Society of Photo-Optical Instrumentation Engineers (SPIE), 2475, pp. 405-416, 1995.