Robert Ballard was born in 1942 in landlocked Wichita, Kansas, grew up in Southern California where his father became chief engineer for the Minuteman missile program at North American Aviation, and was hooked on the ocean by the 1954 film of 20,000 Leagues Under the Sea. After degrees in chemistry and geology at UC Santa Barbara and geophysics in Hawaii, he moved from the Army to the U.S. Navy in 1967 as an oceanographer and liaison to the Woods Hole Oceanographic Institution. In 1977, on a geology expedition to the Galapagos Rift that carried no biologists, the submersible Alvin found hydrothermal vents surrounded by giant tube worms, blind white crabs, and clams living on chemosynthesis. In 1979, on the East Pacific Rise, his team measured black smoker water at about 662 degrees Fahrenheit.

To fund a Titanic search, Ballard pitched his towed camera sled Argo to the Navy in 1982. The Navy agreed on one condition: he first had to secretly inspect the wrecks of the nuclear submarines USS Thresher and USS Scorpion, with the Titanic hunt serving as cover. Studying how imploding submarines scatter a comet tail of debris taught him to search for the trail rather than the hull, and with about 12 days left he found the Titanic on September 1, 1985. He treated it as a mass grave. Later he reached the Bismarck at 15,000 feet, studied the Lusitania, found John F. Kennedy’s PT 109, and explored the oxygen free depths of the Black Sea.

• His mother told him history would remember him for finding a rusty old boat rather than for the vent ecosystems.
• He concluded the Bismarck was scuttled, a view James Cameron’s later expedition disputed.
• Three weeks after finding the Bismarck, his 21 year old son Todd, who had helped in the search, died in a car accident.
• He attributed the Lusitania’s second explosion to coal dust igniting in the empty bunkers, reading the direction the hull plates were bent.
• The Byzantine wreck Sinop D, dated between 410 and 520 AD, sits 320 meters deep with its 11 meter mast still standing.