My wife, my brother, and I went night fishing for catfish in Utah lake. We would always go to the northwest end of the lake where the Jordan river empties into the lake. There are a lot of reeds there which make for good fishing. We found our favorite spot and got our lanterns on and hanging on either end of the boat and started fishing. Within about thirty minutes of good fishing we all noticed a green light. It was being cast out of a single point. This light came down in an almost triangular shape and fanned out very wide. It was very sharp, almost laser like lines. Very uniformed and precise. The light was maybe only 1 inch thick. Nothing was visible to where it was coming from. There was no noise as well during the entire experience. We couldn't see or hear any aircraft. It was completely silent. The light was Northwest of us and slowly moved toward us to the northeast almost as if it was searching or scanning for something. Within a few minutes it come over the top of us. I looked up toward the light and it was extremely bright when I looked directly into it. This was weird because it wasn't casting an extremely bright stream of light. As soon as the light passed over us it disappeared or turned off. We spared no time at all to drop everything and boat the five or so miles back to the boat ramp and go home. We have had no known side effects from this experience other than confusion as to what this light was or its origination.