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National Calibration Center home page


The NPP Government Resource for Algorithm Verification, Independent Test, and Evaluation (GRAVITE) Data Storage and Distribution (DSD) Segment currently hosts VIIRS, CrIS, and ATMS proxy data, and will be sized to hold 180 days worth of NPP mission data, ancillary data, auxiliary data, correlative data and match-up datasets post-launch. These data are made available to the Cal/Val community via the GRAVITE Transfer Protocol (GTP), designed to provide a single, consistent interface for data discovery and retrieval among one or more disparate information storage systems.