NASA / STEREO / Emily Lakdawalla
ISON approaches the Sun as seen from STEREO-A (Nov 21-28, 2013)
This animation contains 264 images captured by the STEREO Ahead spacecraft between November 20 at 14:05 and November 28 at 1:29 UTC. The two vertical lines that cross the image are pixel bleeding from two bright planets (Mercury and Earth), both out of the frame. The smaller comet that appears to cross ISON's path is Encke. As ISON gets very close to the Sun it gets so bright that it saturates the detector, blooming into vertical stripes. Those aren't real; they represent charge spilling over into adjacent pixels from the too-bright comet.