The Moon Mineralogy Mapper is a state-of-the-art NASA imaging spectrometer. Sunlight reflected off the moon enters the telescope and then is passed by mirrors to the spectrometer. In the spectrometer, white light is dispersed into different wavelengths (from 0.43 to 3 micrometers) for every point in an image. Once in orbit around the moon, the instrument generates three dimensional cubes of data that allow scientists to map the composition of the surface.