This past weekend we completed orbit 12,345, and the AIM spacecraft continues to perform nominally, except for the usual lack of receiver bitlock. We have implemented the new CIPS Flat Field imaging command process which requires less bitlock to uplink the command loads for subsequent execution.
SOFIE instrument operations continue to be nominal. The latest PMC season has now progressed into August and data quality remains superb. There have been no processing problems and the data validation/release process is working smoothly. Final revisions to the refraction paper have been completed and the paper has been submitted for publication.
CIPS continues to operate nominally; widespread PMCs are still being observed. Users will now find improved “daily daisies” that contain maps of the clouds on each day. These maps use a new color table to better highlight the dimmer clouds. The flat field images that were to be acquired in late July, which were to be used for ongoing calibration, were unsuccessful because of a spacecraft command error; we are attempting to schedule new flat field images for August. We are continuing to evaluate a new level 4 retrieval algorithm based on an optimal estimation approach. In parallel, we are working to improve our subtraction of the Rayleigh scattering background signal from the measurements. In mid-July noctilucent clouds were reported by ground-based observers at low latitudes, even in the United States. With a test version of the new background subtraction algorithm, we are clearly identifying clouds near the US/Canadian border on 15 July.
Figure: CIPS data from parts of three orbits on 15 July 2009. The structured, light blue/white areas in the middle orbit represent PMCs.