UFO Sighting in Ohio, Ohio on August 17th 2014 – large sphire and was emitting off some sort of gas vapor falling to the groung

My wife and I were out for evening drive in the Amish country and We spotted what I first thought was a large hot air balloon, but as we got closer I did not see any lines or rope attached to it and it was not moving at all. We saw a vapor coming off it and I said "looks like some kind of smoke coming off it, but then I realized smoke rises and this vapor was falling to the ground, we watched it for about 30 minutes and it did not move, then a car came up behind us and we had to move as it could not pass on this country road. again this object appeared to be at least 75 feet in diameter and was leaving off this vapor which was falling to the ground.