All subsystems on the AIM spacecraft continue to function well. We had several periods of bitlock and were able to perform all of our desired command operations. The CIPS Southern Hemisphere Flat Field imaging was performed from Oct 27 - 30.
SOFIE continues to operate nominally. All status flags remain GREEN, and all engineering parameters are well within tolerance.
We have processed the SOFIE mission with the Version 1.03 software. These data were presented at the last AIM science team meeting and will be released in November 2010. The most significant changes are the temperatures obtained from refraction angle measurements below 55km and the inclusion of the full off axis field of view in the forward model. We are currently assembling a document to describe the changes included in the new version and will make it available with the new data.
SOFIE band 2 (330 nm wavelength) was saturated upon launch, but became operational in November 2009 due to gradual darkening of the optics at ultraviolet (UV) wavelengths. The SOFIE UV observations are providing additional insight into PMC particles and meteoric smoke. The figure below shows PMC extinction versus wavelength from SOFIE (black symbols) for the Southern Hemisphere 2009-2010, compared to various model results (in color).
CIPS continues to operate nominally. The operational version 3.21 data for the NH 2010 season have now been reprocessed with the full calibration data set, which contains calibration observations from March, April, June, July and August. The figure below shows the CIPS PMC frequencies for ascending node data in all of the NH seasons thus far observed by AIM. There is significant variability from season to season and throughout each season. Correlating these variations with changes in temperature and water vapor is the subject of ongoing research. All of the data are available on the AIM web site.
Development of the next retrieval version, v4.20, is continuing. We have made significant improvements to the algorithm in the last few weeks. This includes implementing a robust method for detecting clouds that takes into account variations in CIPS sensitivity based on solar zenith angle and view angle. Many test orbits in each season have been processed multiple times with the developmental v4.20 algorithm, as we find and fix small bugs in the codes. Because these tests have taken longer than anticipated, the release of v4.20 has been delayed into October. Finally, we are still in the process of designing calibration observations for implementation in autonomy.