Friend saw and alerted me and my wife to an object that moved eratically in the sky.

it was around 1:00 am and we had just gotten into our sleeping bags after fishing untill late friday night at tarryall reservoir. Just as we were settling in my friend jumped out of his sleeping bag and yelled for us to get up and see this thing in the sky. As we sat up this bright white sphere came around the lake. It started at the inlet end of the lake and we were near the spillway end. The sphere bounced eratically moving up and down in a zigzag motion with the zigs covering at least 50 or 60 feet as it traveled from the inlet end past us to the outlet end and then around us and back towards the inlet end but as it went back the way itcame it just gradually went higher and higher untill it disapered into the clouds that were above at a higher altitude. We talked about what we had seen and we all had seen the same thing. It was about 20 feet in diameter and it was between 200 and 300 feet in altitude untill it started to climb as it left the area. It was the most briliant white light i had ever seen but it didn't put off much light to the ground or the water that we could see. i haven't seen anything like it since then.