The definition and frequency of instrument in-flight calibrations needed during the MIPAS lifetime were defined by a Calibration team before launch and revised during the instrument Commissioning Phase.
Because of the Interferometer Drive Unit anomaly in 2004 (see Mission Operations Overview) , the in-flight calibration strategy had been adapted to the new mission. The main changes affected the spectral resolution, the number of sweeps per scan and therefore the duration of calibrations themselves."
Instrument Settings Changes
Beside configuration changes applied to the instrument in response to the major Interferometer Drive Unit anomaly, few other instrument settings have been modified during the MIPAS lifetime. A summary of those changes is reported in the present section.
In-Flight Calibrations during Full Resolution (FR) mission
In-Flight Calibrations during Optimized Resolution (OR) mission