I was driving down RT 30 east bound and first noticed the object in the air in Matteson IL. I noticed it because it was shaped very odd! It was like something I have never before seen in my life. At first I thought it was an airplane that was completely vertical, but I then realized how lit up the object was. I realized it was entirely too bright to be an airplane! I continued to follow the object while driving down RT 30, and the closer I became, the larger it seemed to get. I tried to speed up as fast as traffic would allow, (approx. 13-15 min has gone by now)all the while keeping my eyes on the object, and then it just disappeared into thin air! It was like someone just turned the lights off! It was gone!