MINIATURE INTEGRATED CAMERA AND IMAGING SPECTROMETER
Artist's rendering by Don Foley (copyright)
If NASA is to conduct missions with smaller spacecraft, it is essential to have correspondingly smaller science instruments. One of the advanced technologies DS1 tested is the Miniature Integrated Camera Spectrometer (MICAS), conceived and developed by a team from the United States Geological Survey, the University of Arizona, Boston University, Rockwell, SSG, and JPL. In one 12-kg package, it includes two black and white cameras, an ultraviolet imaging spectrometer, and an infrared imaging spectrometer plus all the thermal and electronic control. All sensors share a single 10-cm-diameter telescope. With a structure and mirror of highly stable SiC, no moving parts are required; the detectors are electronically shuttered. Spacecraft pointing directs individual detectors to the desired targets.
An imaging spectrometer allows the construction of a picture in which each small element of the picture, known as a pixel, contains information on the spectrum of light; that is, the light is broken into its individual colors, as when you look through a prism. The imaging spectrometers in DS1 work in the ultraviolet and infrared, and the resulting data allows scientists to determine, among other things, the chemical composition of objects being viewed. DS1 determined the chemical composition of asteroid Braille with its infrared spectrometer. Traditional spacecraft would have 3 separate devices to accomplish all the functions of this one.
The ultraviolet detector did not function properly. But, as with all the technologies on DS1, the purpose of the testing was to determine how well it worked to reduce the cost and risk for future missions, so this was a worthwhile experiment.