CELTIC SEA (April 12, 2021) Ensign Chandler Walsh, assigned to the Harpers Ferry-class dock landing ship USS Carter Hall (LSD 50), uses a sextant to check the range of the fast combat support ship USNS Supply (T-AOE 6), not pictured, during a replenishment-at-sea, April 12, 2021. Carter Hall is operating in the Celtic Sea with Amphibious Squadron 4 and the 24th Marine Expeditionary Unit (24th MEU) as part of the Iwo Jima Amphibious Ready Group. (U.S. Navy photo by Mass Communication Specialist Seaman Sawyer Connally)