EnMAP Radiometric Inflight Calibration

Abstract

EnMAP (Environmental Mapping and Analysis Program; www.enmap.org) is a German hyperspectral satellite mission with the declared goal to investigate the Earth’s surface with a so far surpassing quality. The main scientific goals are the ecological assessment of vegetation for agriculture and forestry, of water bodies for coastal zones and inland waters and of land surfaces for geology and soil applications. Hyperspectral remote sensing is an efficient method to obtain the desired environmental information for relative large areas in regular time intervals. This is very useful to produce long term data series for the analysis of climatological behavior of the areas of interest. The satellite operates in a sun synchronous orbit in 650km height with a local time of descending node set to 11:00 h and with an across tilt opportunity, to improve the local revisit time. The instrument foreseen for the hyperspectral remote sensing is the so called Hyperspectral Imager (HSI), consists of two pushbroom spectrometers, covering the optical and near-infrared part of the electromagnetic spectrum. The 232 spectral channels range from 420nm to 2450nm with a resolution of 6.5nm in the visible up to 10nm in the near-infrared. The ground nadir pixel size is 30m, what generates a swath width of 30km with 1000 valid pixels per spectral channels. This relative good pixel resolution makes the instrument very attractive for a lot of local geo-ecological researches. All these data are operationally processed on-ground to standardized products and delivered to the international user community [1].