Report from MUFON:
Date of event: June 4, 2010
Location of event: Chicago, Illinois
"I was in Chicago, IL, at Irving Park @ California walking to my car when my friend and I looked up to see two lights shaped like a cross section of an eye moving in smooth linear directions with a 6 degree course correction made out of the first one done in a precise angle. Then they went into a straight line into the clouds about 15 miles east until the lights faded, most likely increasing altitude for this effect.
It seemed to be not an aircraft, I live by two large airports and can distinguish them readily. The light effect was unlike any lens that I have seen on various aircraft. It wasn't being diffused through water vapor either. I was excited because this was "very" abnormal for the sky in the area.
Usually the planes are flying at sub 2,000 ft altitude as they preform their landing sequence or are beginning to gain altitude for their normal journey."