During Phase I, Space Sciences developed a baseline design for a high performance spaceborne SWIR/MWIR resolved radiometer. Target imagery has been characterized, key system level performance issues determined, and a full PDR conducted. Our infrared imaging experiments, (IRIM's) primary objective is to obtain a high resolution spatial, spectral, and radiometric map of the shuttle glow phenomenon in the near infrared (1.5 to 4.8 micron) region of the electromagnetic spectrum. Employing cryogenically cooled optics, a 640 (H) -X 486-(V) Schottky-barrier-diode platinum silicide focal plane array and eight spectral filters, science information will be obtained in several bands corresponding to emissions of OH, H2O, CO, CO2, NO, and NO2. Additional spatial, spectral and radiometric will be gathered from space shuttle plumes from engine firings with the shuttle in various attitudes and orientations with respect to the velocity vector, the earth's magnetic field, and solar illumination. A third IRIM objective is to collect information from shuttle water dumps, where PPUR water is released from the space shuttle. Water freezes immediately upon release and IRIM will yield valuable scientific information on the rate of condensation and subsequent evaporation, the time constant for evaporation of ice crystals, and the radiometric intensity of these crystals, particularly as they reflect earth and sun shine. Our fourth objective is to study the interaction between the ramming atmosphere and water vapor released from fuel cell purges. In Phase II space sciences will fabricate, test and deliver the IRIM instrument.
