Robert Duane Ballard (born June 30, 1942) is a retired United States Navy officer and a professor of oceanography at the University of Rhode Island who is most noted for his work in underwater archaeology: maritime archaeology and archaeology of shipwrecks. He is most known for the discoveries of the wrecks of the RMS Titanic in 1985, the battleship Bismarck in 1989, and the aircraft carrier USS Yorktown in 1998. He discovered the wreck of John F. Kennedy's PT-109 in 2002 and visited Biuku Gasa and Eroni Kumana, who saved its crew. He leads ocean exploration on E/V Nautilus. Ballard joined the United States Army in 1965 through the Army's Reserve Officers Training program. He was designated as an intelligence officer and initially received a commission as a second lieutenant in the Army Reserve. When called to active duty in 1967, he asked to fulfill his obligation in the United States Navy. His request was approved, and he was transferred to the Navy Reserve on the reserve active duty list. After completing his active duty obligation in 1970, he was returned to reserve status, where he remained for much of his military career, being called up only for mandatory training and special assignments. He retired from the Navy as a commander in 1995 after reaching the statutory service limit.

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