Accurate Nightlight for Satellite Calibration for Weather and Climate Applications

This project’s aim is to develop an Accurate Active Light Source (AALS) that can be fielded at selected calibration sites to address NOAA’s unmet needs and improve the calibration of the Suomi NPP VIIRS Day Night Band (DNB) operating in the high gain stage (HGS) under low light level conditions. The DNB HGS has extreme low-light sensitivity that enables a new generation of nighttime imaging. Many of these emerging applications’ utility however depend on absolute radiometric accuracy and sensor stability. Currently the DNB HGS calibration hinges on transferring calibration from the low and medium gain stages to the HGS using a solar diffuser, which is more than seven orders of magnitude brighter than many of the faintly lit targets imaged using the HGS. As a result, the HGS absolute calibration accuracy under extreme low light may be too low to provide quantifiable information and detect change. Our new AALS will improve our small target radiometry/point source understanding. Combining our national standards-traceable AALS with a sensitive VIIRS nighttime imaging capability has the potential to create game changing new commercial and military applications. Key to commercialization and economic viability is the ability to design and field a cost-effective AALS.