In the course of 71 days in lunar orbit, from 19 February to 3 May 1994, the Clementine spacecraft acquired just under two million digital images of the moon at visible and infrared wavelengths. These data are enabling the global mapping of the rock types of the lunar crust and the first detailed investigation of the geology of the lunar polar regions and the lunar far side. In addition, laser-ranging measurements provided the first view of the global topographic figure of the moon. The topography of many ancient impact basins has been measured, and a global map of the thickness of the lunar crust has been derived from the topography and gravity.

The Clementine mission provided the first ever complete, systematic surface mapping of the moon from the ultraviolet to the near-infrared regions. More than 1.7 million images of the moon, earth and space were returned from this mission. Two star stracker stellar compasses (star tracker camera-I-stellar compass software) were included on the spacecraft, serving a primary function of providing angle updates to the guidance and navigation system. These cameras served a secondary function by providing a wide field of view imaging capability for lunar horizon glow and other dark-side imaging data. This 290 g camera using a 576 x 384 FPA and a 17 mm entrance pupil, detected and centroided stars as dim and dimmer than 4.5 mv, providing rms pointing accuracy of better than 100 p a d pitch and yaw and 450 p a d roll. A description of this lightweight , low power star tracker camera along with a summary of lessons learned is presented. Design goals and preliminary on-orbit performance estimates are addressed in terms of meeting the mission's primary objective for flight qualifying the sensors for future Department of Defense fights.

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We describe a ground-based visible-band imaging Fourier transform spectrometer for astronomy. Astronomical observations benefit from hyperspectral datacubes of variable spectral resolution. The low-light conditions of visible-band astronomy impose requirements of high throughput and step-scanning.We are developing a ground-based visible-band imaging Fourier transform spectrometer (IFTS) for astronomy. An IFTS can obtain a spectrum for every spatial resolution element, and a twooutput system has high efficiency, counting every photon. The spectral resolution of an FTS can be varied from observation to observation, and for a compensated system spectral resolution across a broad band can be as low as a few.Some astronomical observations lie in the regime where every element in a hyperspectral datacube of the field of view would contain significant information. Such problems are barely addressed by current observations and technology, but represent some of the most intriguing problems of modem astrophysics. This astronomy advocates a wide-field imaging spectrograph that is efficient in this limit. An IFTS provides these capabilities in a low-cost, high throughput, compact design. It provides the only efficient means of conducting spectroscopic surveys without object pre-selection or restrictions imposed by spectrometer geometry.The current Livermore instrument is based on an interferometer designed by Bomem to demonstrate long term step-scanning stability at visible wavelengths. The optomechanical design is apochromatic dual-output with two Pelletier-cooled CCD cameras. We have taken two different instruments to astronomical observatories and will present some of our design and peculiar astronomical design constraints as well as the observations performed.

Lawrence Livermore National Laboratory developed a space-qualified High Resolution (HiRes) imaging LIDAR (LIght Detection And Ranging) system for use on the DoD Clementine mission. The Clementine mission provided more than 1.7 million images of the moon, earth, and stars, including the first ever complete systematic surface mapping of the moon from the ultraviolet to near-infrared spectral regions. This article describes the Clementine HiResLIDAR system, discusses design goals and preliminary estimates of on-orbit performance, and summarizes lessons learned in building and using the sensor. The LIDAR receiver system consists of a High Resolution (HiRes) imaging channel which incorporates an intensified multi-spectral visible camera combined with a Laser ranging channel which uses an avalanche photo-diode for laser pulse detection and timing. The receiver was bore sighted to a lightweight McDonnell-Douglas diode-pumped NdYAG laser transmitter that emmitted 1.06 pm wavelength pulses of 200 mJ/pulse and 10 ns pulse-width. The LIDAR receiver uses a common F/9.5 Cassegrain telescope assembly. The optical path of the telescope is split using a color-separating beamsplitter. The imaging channel incorporates a filter wheel assembly which spectrally selects the light which is imaged onto a custom 12 mm gated image intensifier fiber-optically-coupled into a 384 x 276 pixel frame transfer CCD FPA. The image intensifier was spectrally sensitive over the 0.4 to 0.8 pm wavelength region. The six-position filter wheel contained 4 narrow spectral filters, one broadband and one blocking filter. At periselene (400 km) the HiResLIDAR imaged a 2.8 km swath width at 20meter resolution. The LIDAR function detected differential signal return with a 40-meter range accuracy, with a maximum range capability of 640 km, limited by the bit counter in the range return counting clock. The Imagery from the HiRes is most useful for smaller scale topography studies, while the LIDAR data is used for global terrain and inferred gravity maps.