CALIBRATION OF THE IMPROVED STRATOSPHERIC AND MESOSPHERIC SOUNDER .2.OPTICAL ALIGNMENT, SPATIAL, AND PRESSURE MODULATOR CALIBRATIONS

In Part I the Improved Stratospheric and Mesospheric Sounder instrumen t and its calibration facility were described, and the results of the radiometric and spectral calibrations were presented. In Part II the r emaining prelaunch calibrations are discussed. The optical calibration s include the procedure used to coalign the different spectral channel s and the mapping of the resulting instantaneous fields of view. These maps revealed detailed stray light processes within the instrument. T he remaining optical calibration is of angular motion of the instrumen t scan mirror. The pressure modulator calibrations consist of the fill ing procedures and algorithm validation, which allow the gas condition s within the modulator to be determined from the instrument telemetry. Some overall conclusions to the calibration process are drawn.