UV Observations During The STARLAB Space Shuttle Mission

STARLAB is a seven-day Spacelab mission, presently scheduled for 1991, whose principal objective is to demonstrate acquisition, tracking, and pointing technology relevant to SDI requirements. This will be accomplished using various onboard sensors and lasers, and ground-launched missiles with target boards and other diagnostics. The STARLAB mission also involves a number of other experiments, including measuring and cor-recting optical aberrations and atmospheric effects on laser propagation, assessing the feasibility of submarine laser communication from space, and making high-resolution, multi-wavelength observations of missile plumes and hardbodies, and space, earth, and limb backgrounds. The STARLAB UV camera assembly (UVCA), developed by Lockheed's Palo Alto Research Laboratories, operates in the 0.20 to 0.32 urn waveband, and will support the passive plume imagery and background measurements. The UVCA can be operated automatically by the experiment computer or manually, with the shuttle payload specialist selecting filters, gain settings, and data-taking modes. The UVCA system consists of an f/25.5, 20-cm aperture Cassegrain telescope with an 8-filter wheel, and a two-stage, UV/visible image intensifier coupled to a CCD array. The Backgrounds Measurements experiment will examine the radiant intensities, as well as the spatial, spectral, and temporal variabilities, of the earth and limb. Pre-launch and on-orbit camera calibrations and characterizations will allow for absolute radiometry and camera boresighting. For all measurements, the onboard flight computer will store target coordinate locatidns and scene sun angle if appropriate. Though the STARLAB control system will normally point the line-of-sight and acquire data, the payload specialist will be able to manually point the LOS to view targets of opportunity such as hurricanes, abnormal weather patterns, aurora, nocti-lucent clouds or other mesospheric structures.