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VIIRS/NPP On Board Calibrator (OBC) IP NRT

Published by NASA/GSFC/SED/ESD/BSL/VCST;NASA/GSFC/EOS/ESDIS/LANCE MODIS | National Aeronautics and Space Administration | Metadata Last Checked: February 21, 2026 | Last Modified: 2026-02-17
The VIIRS Level 1 and Level 2 swath products are generated from the processing of 6 minutes of VIIRS data acquired during the NPP satellite overpass. The VIIRS sensor has 5 high-resolution imagery channels (I-bands) that have 32 detectors (32 rows of pixels per scan), with twice the resolution of the M-bands and the DNB, that span the wavelengths from 0.640 µm to 11.45 µm.The VIIRS on-board calibrator and engineering data product is referred to by it's shortname, VNP02OBC. The VIIRS On Board Calibrator IP file contains space view, solar diffuser, on-board calibrator blackbody (OBCBB) view observations, the associated gain state and HAM side information, and all engineering and housekeeping data, including unscaled data from the Solar Diffuser Stability Monitor (SDSM)/VIIRS Earth View Radiometric Calibration Unit and the Solar Diffuser GEO angles.For additional information, see the Operational Algorithm Description (OAD) Document for the L1B product (http://npp.gsfc.nasa.gov/sciencedocs/2015-08/474-00090_OAD-VIIRS-CAL-GEO-SDR_H.pdf). The document describes how VIIRS operates in space and provides the equations implemented by the L1B software to generate the MODIS Level 1 intermediate products. It is a summary document the presents the formulae and error budges used to transform VIIRS digital counts to radiance and reflectance.file_naming_convention = VNP02OBC.AYYYYDDD.HHMM.CCC.nc AYYYYDDD = Acquisition Year and Day of Year HHMM = Hour and minute of acquisition CCC = Collection number nc = NetCDF5

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