VJ203MOD represents the short-name for the Joint Polar Satellite System-2 (JPSS-2/NOAA-21; referred to hereafter as J2) platform-based NASA VIIRS L1 terrain-corrected geolocation product, and contains the derived line-of-sight (LOS) vectors for each of the 750-m moderate-resolution, or M-bands. The geolocation algorithm uses a number of inputs that include an Earth ellipsoid, geoid, and a digital terrain model along with the J2 platform’s ephemeris and attitude data, and knowledge of the VIIRS sensor and satellite geometry. It produces geodetic coordinates (latitude and longitude), and related parameters for each VIIRS L1 pixel. The VJ203MOD product includes geodetic latitude, longitude, surface height above the geoid, solar zenith and azimuth angles, sensor zenith and azimuth angles, land/water mask, and quality flag for every pixel location. VJ203MOD provides a fundamental input to derive a number of VIIRS M-band higher-level products. The data product described in this landing page is a v2.1 collection and its data record starts from February 10, 2023.

Geolocation Accuracy The overall geolocation accuracy for the J2 VIIRS Level-1 data is nominally good. The nadir-equivalent geolocation accuracy is within 70 m uncertainty (1-sigma Root-Mean-Squared-Error), which is well within the specified requirement of 125 m (1-sigma RMSE).