False colour reveals interesting movement in sprite

Just an idea that came up when seeing two nearly identical frames that have been recorded of the same sprite that we just captured this night. The above image is a false-colour composite of two frames separated by 40 msec. The first frame is given the red color. The second frame the green color. It appears that the illuminations have slid upwards along the bottom tendrils during this time. Note that the same happens at the top of the sprite.