On July 29, 1955, a family outing on Moon Lake in Duchesne County, Utah, ended when a rented aluminum boat with five people aboard capsized and sank in the lake’s deepest area, where depths reached 115 to 125 feet. Witnesses said the boat’s trawling gear became entangled in one of its two motors; both motors reportedly ran as the boat circled uncontrollably, then overturned and sank quickly. A.G. and Lucy Smith were rescued by another boat, but Calvin Wayne Bosen, his wife Ruby Mae Bosen, and Ruby’s brother Clarence Delmer Simons vanished into the water and were presumed drowned.

Calvin and Ruby were Salt Lake City residents and parents of two sons and a daughter. A large search followed, including boats dragging the area with grappling hooks and an aerial survey, but the lake’s extreme depth prevented recovery. Searches continued in the days, months, and years afterward and none of the three has ever been found. The Duchesne County Sheriff’s Office lists the case as an active missing persons investigation.

If anyone was on Moon Lake that day or has information about the boat, the missing occupants, or recovery efforts, please share what is known.