I was hunting for coyotes at night. I was standing in the edge of a woods while a corn field was being shelled when I noticed a dim light coming through the tree tops at about 20 feet above the ground. I was using a pair of gen 3 pvs 7 when I saw it. It was around the size of a volley ball or a basket ball. I lowered the pvs 7's and I could not see it. I watched it as it came through the tree tops and stopped just outside the woods as 1 of the combines was coming. It sit there as the combine was turning around it changed position 2 times like it was looking at it from different angles. After the combine started the other way it took off to the South West. It was hard to judge the speed but I would guess 60 to 70 mph was as fast as it went and you could not see it without night vision and it stayed at the same elevation until it was out of sight. If there was a pilot in it he would have had to be very small. I think it had to be some kind of probe. If it knew I was there it showed no sign of it. I have never heard of a UFO that could only be seen through night vision.