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Image name: RECENT_POINTING.png (click image to enlarge)
Image size: 5.730 KB (512x512)
Date submitted: 19-Dec-1995
Description:
Plot of the Y sun-center coordinates since 16 August, showing that the rapid upward trend appears to have reversed in the pattern of the seasonal effect noted earlier. This illustration shows that a "normal point" redefinition every two weeks would be preferable in the sense of making a tighter pattern of terminator images possible. To implement this will require re-writing and uploading all the pointing OG's every two weeks, since they are absolute (relative to the spacecraft hardware-defined coordinates) and not just offsets. Software to ease this task will be put together, and we are thinking about recommending that the new "pointing maintenance" scheme start at the beginning of January with a position that is about one arc min N (S/C motion) of the current position. We will check to be sure that this new normal position is clear of HXA fiducial marks, since this degrades the coalignment between SXT and HXT slightly. Hudson and Savy, 19-Dec-95
