[an error occurred while processing this directive] STEREO

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Image artifacts - Spacecraft rolls

Periodically, the STEREO spacecraft are rolled around the Sun-pointed axis for calibration purposes. The result can be some very odd coronagraph images as shown below. This is because the processing algorithms don't work properly during the roll. The EUVI images are relatively unaffected, except the position of Sun center moves around.

Roll effect on STEREO Ahead COR1   Roll effect on STEREO Ahead COR2
The effect of observing during a spacecraft roll, as seen by STEREO Ahead COR1 on November 24, 2009. Click on the images to see movies of the event.   Same event as seen in COR2
Roll effect on STEREO Ahead HI1   Roll effect on STEREO Ahead HI2
Same event as seen in HI1   Same event as seen in HI2

Back to image artifacts page.

Last Revised: Tuesday, 25-Nov-2025 11:58:33 EST
Responsible NASA Official: [email address: therese.a.kucera<at>nasa<dot>gov]
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