Visible Infrared Imager Radiometer Suite (VIIRS) instrument on-board the National Polar-orbiting Operational
Environmental Satellite System (NPOESS) Preparatory Project (NPP) satellite is scheduled for launch in October, 2011.
It is to provide satellite measured radiance/reflectance data for both weather and climate applications. Along with
radiometric calibration, geometric characterization and calibration of Sensor Data Records (SDRs) are crucial to the
VIIRS Environmental Data Record (EDR) algorithms and products which are used in numerical weather prediction
(NWP). The instrument geometric performance includes: 1) sensor (detector) spatial response, parameterized by the
dynamic field of view (DFOV) in the scan direction and instantaneous FOV (IFOV) in the track direction, modulation
transfer function (MTF) for the 17 moderate resolution bands (M-bands), and horizontal spatial resolution (HSR) for the
five imagery bands (I-bands); 2) matrices of band-to-band co-registration (BBR) from the corresponding detectors in all
band pairs; and 3) pointing knowledge and stability characteristics that includes scan plane tilt, scan rate and scan start
position variations, and thermally induced variations in pointing with respect to orbital position. They have been
calibrated and characterized through ground testing under ambient and thermal vacuum conditions, numerical modeling
and analysis. This paper summarizes the results, which are in general compliance with specifications, along with
anomaly investigations, and describes paths forward for characterizing on-orbit BBR and spatial response, and for
improving instrument on-orbit performance in pointing and geolocation.