JPSS-3 VIIRS day-night band pre-launch radiometric characterization

The Joint Polar Orbiting Satellite System (JPSS) is a partnership between NASA and NOAA to build new generation polar-orbiting operational environmental satellite system which started with the launch of the Suomi NPP in 2011. JPSS- 3 will be the 4th satellite in JPSS program and is scheduled to launch in 2026. The flagship instrument on the JPSS satellites is the Visible Infrared Imaging Radiometer Suite (VIIRS) which provides visible and infrared imagery in support of a variety of land, ocean and atmospheric products. JPSS-3 VIIRS much like the first three VIIRS instrument will feature the panchromatic Day-Night Band (DNB), which is capable of obtaining high quality imagery over a wide range of illumination conditions from daytime to reflected moonlight using a wide bandpass in combination with time delay integration. JPSS-3 VIIRS underwent a rigorous prelaunch test program carried out by the sensor vendor, Raytheon, El Segundo in ambient configuration in 2019 and flight-like conditions in thermal vacuum in late 2020 into early 2021. As part of this test program a series of tests to characterize its spatial, radiometric, spectral, and functional performance at the instrument level were completed. The DNB radiometric measurements were subsequently analyzed by both vendor and government teams. These analyses are critical to show compliance with the sensor design specifications as well as the ability of the instrument to produce high quality imagery and radiometry similar to the two instruments currently in operation. Presented in this work is the radiometric and spectral performance of the DNB including dynamic range, sensitivity, radiometric uncertainty and non-linearity along with a discussion of the performance in comparison with its predecessors S-NPP, JPSS-1 and JPSS-2 VIIRS.