Image Products from the new hyperspectral sensor DESIS

Abstract

The DLR Earth Sensing Imaging Spectrometer (DESIS) instrument is a new hyperspectral sensor integrated in the Multi-User-System for Earth Sensing (MUSES) platform from Teledyne Brown Engineering. It will be launched to ISS in early 2017 with a four month commissioning phase, followed by the operational phase at least until 2020. The DESIS hyperspectral instrument is realized as a pushbroom imaging spectrometer spectrally sensitive over the VNIR range from 400 to 1000 nm with a spectral sampling distance of about 3 nm employing a 2-dimensional back illuminated CMOS (Complementary Metal Oxide Semiconductor) detector array. The optical design is based on the Offner-type grating spectrometer widely used in hyperspectral imaging. The Ground Sampling Distance (GSD) at nadir view depends on the flight altitude of the ISS and varies approximately between 25 m and 32 m resulting in a swath width of about 30 km. DESIS is equipped with a Pointing Unit (POI) consisting of a rotating mirror in front of the entrance slit allowing a forward and backward viewing change up to ±15° w.r.t. the nominal (e.g. nadir) view. The POI can be operated in a static mode with 0.9° angle steps for the viewing direction and in a dynamic mode with up to 1.5° change in viewing direction per seconds. This allows, besides standard Earth data products, acquisition of