Bright UFO enters atmosphere then makes 90 degree turn 6/4/16 Chicago

I was out on my apartment porch, enjoying the early evening weather. I have always been an astronomy enthusiast and make an effort to look at the sky and test my knowledge of constellations and solar system objects. I was looking West over the buildings, and noticed the sudden appearance of a bright light between the constellations Gemini and Auriga. The light entered in a North-East direction and at first I thought it was a meteorite or iridium flare. It had a slight trail of light following it to a tapered point. What really caught my attention was that it appeared to decelerate. The UFO object then abruptly stopped and executed a 90 degree turn, headed North. The UFO object then continued on the new trajectory for about 5 seconds until it disappeared. The UFO did not make any perceivable noise, nor did it move like a conventional aircraft / natural object. The only other object in my sight was a commercial airplane, traveling in a South East direction a few minutes prior.MUFON CMS# 76802 UFO Sighting occurred on 6/4/16