John Nesterowicz was a Starfleet officer in the 24th century. In 2367, as a lieutenant aboard the USS Enterprise, he was a WarpField Tech 2 for the Third Shift Antimatter Operations Unit. He was listed as being on duty in the Engineering Division Duty Roster. This roster was on display via the desktop monitor in the ready room. (TNG: "Suddenly Human" , okudagram) In 2371, he was a crewmember aboard the USS Voyager. He was among the crew stranded in the Delta Quadrant, when Voyager was forcefully brought there by the Caretaker.