JPSS-2 VIIRS Day–Night Band Prelaunch Radiometric Calibration and Performance

Abstract

The first two flight models of the Visible Infrared Imaging Radiometer Suite (VIIRS) instrument continue to operate onboard the Suomi National Polar-orbiting Partnership (S-NPP) and NOAA-20 spacecrafts. The third flight model is set to be launched as one of a complement of instruments onboard the Joint Polar–orbiting Satellite System-2 (JPSS-2) satellite. In addition to its 14 reflective solar bands and 7 thermal emissive bands, VIIRS has a unique Day-Night Band (DNB). The DNB is a panchromatic imager based on CCD detectors, covering a spectral range of about 500 – 900 nm. The DNB is made up of three gain stages, allowing the sensor to operate over a large dynamic range (3×10-9 - 0.02 W/cm2/sr). As part of VIIRS pre-launch ground testing, the DNB has been characterized to determine its functionality and performance under a space-like environment. The results are compared against the design specification and to previous VIIRS flight models when applicable. This paper presents a comprehensive summary of the VIIRS DNB prelaunch testing and the results of radiometric and spectral assessments. The expected impact to on-orbit operations and calibrated data products are also discussed.