For most of his distinguished career, Dr. Robert Ballard has been a scientist concerned about mapping the deep seas. But television and the explorer's urge to visit untouched places have combined to make him a historian, too.
Tonight he invites cable viewers to journey back to one of the deepest secrets of World War II.
In "The Lost Fleet of Guadalcanal," the latest edition of "National Geographic Explorer" (premiering at 9 p.m. on TBS), Dr. Ballard documents an expedition to the floor of the so-called "Iron Bottom Sound" off the tiny South Pacific island of Guadalcanal.
In August 1942, roughly 50 Japanese and Allied ships went to the bottom there in a prolonged, crucial battle that helped turn around the Japanese advance toward Australia.
The Ballard expedition helped mark the 50th anniversary of the battle last summer. Using the Sea Cliff DSV-4, a deep-sea submersible on loan from the U.S. Navy, explorers swept a 300-square-mile area and located 14 sunken warships. "The Lost Fleet of Guadalcanal" offers eerie footage of a dozen of them.
"They're just frozen in combat. You can see the camouflage paint is still intact," says Dr. Ballard.
And the 2 1/2 -hour documentary, introduced by a Pacific campaign veteran, former President George Bush, benefits from eyewitness accounts of a group of Guadalcanal survivors from the United States, Australia and Japan.
"This is the first time I've taken survivors on an expedition, . . . and they just bring it to you in such catharsis," says the explorer, best known to TV audiences for his programs exploring the deep remains of the luxury liner Titanic and the German battleship Bismarck.
"Sometimes we let them drive [the remote-controlled video monitoring vehicle], such as over the Canberra when an Australian officer cried, 'I was standing right there' when the cruiser was hit. He could see his post on the bridge," Dr. Ballard recalls.
"This is a battlefield that has never been seen," he notes. And the preservative forces of deep, cold water make this site of conflict far more informative than any battlefield site on land.
"There are not people lying there anymore," he says of terrestrial sites. Yet at Guadalcanal, "the insides of these ships are tombs, untouched."
The expedition did not enter any of the ships, out of respect to the dead. Instead, the submersible vehicle affixed bronze memorial plaques to each of the vessels.
While the explorers did not find bodies outside the hulls -- exposed remains would have long since been consumed by predators and the sea's corrosive effect on bones -- they did photograph sobering sights.
"All around these ships are shoes, and pairs of shoes, and somehow that is even more difficult to see," Dr. Ballard says.
Yet, he says, a fundamental human trait draws him, and by extension TV viewers, to contemplate such morbid scenes.
"There's this thing about us that wants to know about ourselves. . . . And human calamities such as the Titanic or Lusitania just fascinate people," he observes.
The human urge to explore also makes him vow to continue going "to places on this planet that have never been visited before."
He predicts, in fact, that "The next generation will explore more of the Earth's surface than all of the generations that have come before," through development of technology to go ever deeper beneath the planet's predominantly watery surface.
"We have better maps of Venus now than we have of the oceans," he says.