Three light triangle over cabins near Grand Rapids, MNThis may well have been a regular aircraft, although, to me it seemed very unusual. I was at a cabin resort near Grand Rapids, MN. While walking alone from one cabin to another at about 10:30 PM on a clear night, I looked up to see, between the trees, a set of three white lights in a trangular fromation going overhead. I only got a good look at it for about 15-20 seconds. It seemed very low in the sky and was traveling fairly slowly. There was absolutely no sound associated with it and no flashing lights of any kind, nor any red lights like you would see on a normal aircraft at night. The lack of sound or flashing lights is what made it unusual. The cabin area was quiet, being in the countryside vacationers already settling in for the night. So, if there had been noise from the craft I definately would have heard it. Is there any type of normal aircraft that would behave in this way?