It was late October 2012, cannot remember exact date. It was 930 at night I was walking from my garage to my house I just happened to look up and noticed two extremely bright lights one of them red, one green moving east to west in a staggered formation. The lights were moving at an extremely high rate of speed. I estimate the altitude of the objects are between five and 10,000 feet, but possibly much lower. No sound was emitted. The flight path was directly over my location. When the lights were about 45 degrees to the west both disappeared. At my estimated altitude and the rate of movement I estimate a speed of 4000 mph. The sky was clear and the weather was calm. At my location I can observe commercial airliners at lower altitudes on ascent and desent to and from Eppley. I am absolutely positive this event was not an airplane.