Strange object seen hovering overhead in the eveing sky in Humble, Texas.We were walking in the neighborhood, and in the same moment, both of us looked up to see a shape in the air. At first we thought it was a baloon because the way it swiveled up into the sky, but realized it couldnt be after it seem to drop in altitude, then swirl. At first it appeared to be a sphere shape, then moved and rotated and looked more like an oval. We realized how high it was when a commercial airplane flew below it and we could see the definate shape of an airplane, with lighs, but our craft had no definate shape and absolutly no lights. We watched in awe for about 20 minutes, people would stop and talk to us, but we were in allmost in a trance and didnt even respond. A guy rode by on a bike, and said something about "lightning..." to us, and we looked away for a second and when we looked back up- it was gone, we searched the sky for about 5 minutes trying to find it- but it seemed to have dissapeared. We live about 5 minutes from Bush Intercontintal Airport- we know what planes look like and sound like when they fly over at..even at high altitudes, this made no sound and had no color, and we are both positive it was not a plane.