AIM - The Mission

STATUS: 07.01.10

Spacecraft Status

The spacecraft has performed well over these past several weeks with the exception of usual lack of bitlock. On June 21 we experienced a few minutes of bitlock and during this time uploaded commands. We booted SOFIE to the new flight software code image on June 23. GATS is reporting that everything looked good. We also started the June Northern Hemisphere CIPS Flat Field observations.

Instrument Status

SOFIE continues to operate nominally. The switchover to the new autonomy FSW (Flight Software) image completed on June 23, 2010 at 18:45Z. All status flags remain GREEN, and all engineering parameters are well within tolerance.

Release 2 SOFIE data processing is complete through June 26, 2010 and the data has been reviewed by the SOFIE personnel before release to the public. The next version of software is nearing completion for processing next month. Recently we added a minor change to the Level 0 time tagging that indicates the starting and ending times of the balance portion of the event. We have also implemented the NO detector thermal response correction software into the Level 1 production code. We completed an error analysis to characterize the most important sources of systematic error in the retrieved SOFIE H2O.

SOFIE is now observing its seventh PMC season, and the second season with band 2 ultraviolet measurements. These data are being used to determine particle size and concentration, to altitudes of 1-4 km higher than previous results using NIR observations.

CIPS continues to operate nominally, and we are seeing widespread clouds poleward of 70° latitude on a daily basis. Because of a lack of bitlock, we did not obtain calibration observations for the month of May. We have, however, obtained them for March, April, and June. As we acquire more statistics each month, the factor that we use to normalize the cameras to one another changes slightly. This affects the data at a very low level that can be discerned quantitatively, but is not yet qualitatively noticeable in the daily daisies. For the operational processing, we continue to use the normalization (and delta flat) data from March.

We are continuing to improve our next version of the retrievals, which will be released in September as version 4.20 – the development version is currently called 4.10. The figure here compares the daily daisy from 7 June 2010 for versions 3.21 (operational), and 4.10. On this date, clouds were dim and very sparse, so it is a good test of the background subtraction algorithm. The daisies are plotted with different color scales, but note the improved cloud detection in version 4.10. Modifications that are in progress for v4.10 include improvements to the cloud detection threshold so that it better accounts for the varying sensitivity with solar zenith angle, and detailed simulations to enable an accurate error analysis.