Dr. Robert Ballard. Best 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. Meeting Robert after a lecture on finding the Titanic, I surprised him by asking "How many WWII aircraft did you come across during your explorations under the ocean in Guadalcanal" ? His reply - "To be honest, I was actually more concerned with the number of sunken WWII Warships" !