Was Driving in a rural area in Carlinville Illinois when we seen a very huge light in the North sky that appeared to have searchlights coming down from it. We stopped the vehicle and watched it for approximately three minutes at which time it was stationary and not moving. After the first three minutes the beams of light that was under it left and it began to move. Once it started moving it looked like one huge bar or rectangular shape and it was bigger than anything I've seen in the sky. Made no sound and once it started moving it moved fast. We turned the car around and proceeded to try to follow it. Followed it maybe three or four minutes when due to its speed we totally lost it. It was moving from north to south and was completely silent there was nothing blinking on it the lights were solid. We apparently weren't the only ones who seen it because when we stopped to watch it another car stopped alongside of us and asked us what that was and of course we had no clue. It left no vapor trail. Have never seen anything like it before.