Robert Ballard

Describing the event, Ballard wrote: "As the images on the video screen grew more and more vivid -- large pieces of twisted hull plating, port-holes, a piece of railing turned on its side -- for the first time since I had started on this quest 12 years before, the full human impact of the Titanic's terrifying tragedy began to sink in. Here at the bottom of the ocean lay not only the graveyard of a great ship, but the only fitting monument to the more than 1,500 people who had perished when she went down." Returning a year later with Alvin, a three-person manned submersible, Ballard carefully explored the wreck, capturing footage later used in the 1997 motion picture "Titanic."

As a child, fueled first by Jules Verne's "20,000 Leagues Under the Sea," Ballard began reading accounts of early deep-sea exploration by people like William Beebe, who built a crude bathyscaph in 1930, diving to depths of 1,500 feet in waters off Bermuda. Beebe wrote, and Ballard read with grim relish, that if the bathyscaph sprang a sizable leak, the sheet of water entering the capsule would cut a man in half; even a narrow stream of water caused by a pinprick hole, or a misplaced rivet, was capable of drilling straight through Beebe and his partner, Otis Barton, as they sat bolted inside the chamber.

In an interview from 1991, Ballard said: "Like the space shuttle, you could never lose sight of the fact that you were doing something dangerous. It may be apparently routine, but if you mess it up, it will bite you, and it has over the years. I had a fire once -- not in Alvin, in a French bathyscaph -- at 9,000 feet, and almost died."

But to Ballard, the risk of any project is a reasonable trade-off for the answers it might provide. You can get a better sense of how Ballard views his expeditions by taking a look at the names he gives some of his equipment and projects: There's the Argo, named after the ship that carried Jason to the Golden Fleece in Greek mythology; the Little Hercules, a one-man submersible named after the mythological strongman; and the JASON Project, a program Ballard began in 1989 that allows schoolchildren to participate in live video feeds of Ballard's expeditions.

The mythological characters keep popping up for a reason. Ballard views his expeditions as epic adventures in search of a deep-sea Golden Fleece, hidden and preserved for centuries by the conditions at the bottom of the ocean. His discoveries should matter to all of us. In his most recent book, "Graveyards of the Pacific," he writes: "I've been doing this a long time now -- from the Atlantic to the Pacific to the Mediterranean to the Black Sea -- peering through murky depths to see what history can tell us, getting a new and unique perspective on things that shaped our view of the world, and ourselves."

Before 1985, Ballard's research efforts concentrated on the geological formations of the ocean floor and the unusual species that populate them. Discovering the Titanic marked a shift in his career from studying natural history to studying human history.

He was the first American to enter, photograph and map regions of the mid-oceanic ridge, an underwater mountain range -- more than 40,000 miles long and up to 500 miles wide -- that runs in a continuous belt around the Earth. The ridge is the largest geological feature on the planet, zigzagging among the continents, bisecting the oceans and rising 15,000 feet above the seafloor. In other words: Been there, done it, mapped it.

While on the Galapagos Hydrothermal Expedition in the late 1970s -- to investigate unexpected rises in temperature on the ocean floor -- Ballard discovered and described several new species living near hydrothermal vents 9,000 feet below the surface.

In "Eternal Darkness," Ballard describes what he saw: "Warm water shimmered up from cracks in the lava flows. It was turning a cloudy blue as manganese and other minerals, carried from deep within the seafloor, precipitated out of solution to form a solid coating on the cooler surrounding rocks. But that was not all. The seafloor was teeming with life."

For several days, Ballard explored the hydrothermal vents, taking specimens and preserving them in Russian vodka purchased at port in Panama. In other words: Been there, done it, mapped it, sampled it and pickled it in vodka.

He writes: "The dominant macroorganism living near the vent openings was the giant red tube worm, or Riftia pachyptila. These spectacular organisms form large clusters, or hedges, standing up to ten feet high. All around them we could see shimmering flows of milky white, mineral-rich water."

This was new: worms that looked more like B-movie monsters, growing in great thickets on the seafloor. They have no mouth, no eyes and no intestinal tract. They're ugly. They're "bursting out of John Hurt's stomach and flying across the room in a bloody mist" ugly. Protected by a hard, white outer casing, the worms stand upright in clusters, poking the red tips of their bodies into the surrounding water to absorb oxygen.

Like many of the species in the Galápagos' rift valley, they had never before been described and were unknown to science; like his heroes before him, both real and fictitious, Ballard had successfully descended into the unknown, the lost world, and brought back something exotic for the rest of us to inspect.

The tube worms represented the strange otherworldliness of the ocean that has fascinated Ballard for so long; they were his Golden Fleece, as were the wreck of the Titanic, the mid-oceanic ridge and so many of the other discoveries Ballard has made during his extraordinary 40-year career. He has undoubtedly spent more time underwater than anyone else alive.

In a 1999 interview, Ballard said: "If you were to compare the number of people who have been into outer space with the number who have been to the average depth of the ocean, I think more people have been in outer space. Neil Armstrong and Buzz Aldrin walked on the moon before we went to the largest mountain range on Earth, which lies under the ocean."

And that's what makes Ballard's career so extraordinary. For more than 10 years, he spent four months of every year at sea, exploring the seafloor. The way Ballard sees it, we don't need to go into space, and we don't even need to trek to the Amazon Basin, or to frozen Antarctica, when thousands of square miles of ocean floor remain unexplored. Just a few miles off the coast, off any coast, are discoveries to be made.

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