To the person who said the mist looks like smoke & asked if it was visible in the day:
I was with Andy when this picture was taken, & no, it wasn't visible. There wasn't any smoke or any mist in the area at all. It was a clear day. There was nothing unusual at all. There was nothing in the air when this picture was taken. It's large, & we would have seen it if it was visible to the naked eye.
To the person who said the mist is explainable, then please explain what is it then?