One of the two Earth-sensing payloads carried aboard Landsat 4 and 5, the multispectral Scanner being the other on 4 and 5. It is a non-photographic imaging system, which utilizes an oscillating mirror and seven arrays of detectors, which sense Electromagnetic Radiation in seven different spectral bands. The Thematic Mapper is a derivative of the Multispectral Scanner generation of sensors, but it achieves much greater Ground resolution, better spectral separation, improved geometric fidelity, and greater radiometric accuracy and resolution.