June 30 is the birthday of Robert Ballard, former U.S. Navy officer and professor of oceanography at the University of Rhode Island. He is noted for his work in maritime archaeology and the archaeology of shipwrecks. He discovered the wreck of the RMS Titanic in the North Atlantic on September 1, 1985. . . . You know what happened next: movies, books, tchotchkes, the careers of Leo DiCaprio and Kate Winslet . . . Few people realize, however, that Ballard’s trip in the summer of 1985 was financed by the U.S. Navy for secret reconnaissance of the wreckage of two Navy nuclear-powered attack submarines, the USS Scorpion and the USS Thresher, which sank in the 1960s, not for the Titanic.