The recent "UFO sighting" at O'Hare airport (November 2006) was explained as an illusion due to weather conditions. What sort of weather conditions would cause something like this?
Posted January 30, 2007
Just for illustration, here are some addresses with lenticular cloud photos, some mirage imagery and explanations, and a couple of "hole-punch" cloud shots:
Also, for those unfamiliar with the UFO story, here's a column from the Chicago Tribune: