A series of 15 photos put together into a time lapse sequence. There is a dark bluish area in Jupiter's lower dark band, along with a more diffuse bluish area that can be seen emerging from the right about half way through this sequence. At first I thought this was a dust mote or optical problem. It turns out it was real. Amateur Jupiter watchers noticed this too and speculated that it was a somewhat unusual but natural occurrence known as a dark plateau intrusion. A phenomenon that looked like this occurred many years ago when comet Shoemaker-Levy 9 slammed into Jupiter and disturbed it's weather pattern.