Overhead view of Thresher's upper rudder, photographed from a deep-sea vehicle deployed from USNS Mizar (T-AGOR-11). The view shows draft markings on the rudder side and a navigation light at its top. The original photograph bears the date October 1964. Thresher was lost on 10 April 1963. See Photo # NH 97546 for a view of this rudder taken prior to the submarine's loss. Official U.S. Navy Photograph, from the collections of the Naval History and Heritage Command.