Systematic navigation error on NOAA-12 AVHRR images

Abstract

A systematic and unusual navigation error appears on the AVHRR images from the satellite NOAA-12. The results of the C.M.S. automatic navigation adjustment obtained from 24 September to 8 December 1991 have shown a line error linearly dependent on the pixel number with a constant slope (mean value: 0-0058 line per pixel). The relative alignment of HIRS-2 with respect to AVHRR has been studied on a few orbits and the scanning planes of the two instruments may be considered as parallel.