A rare deep-sea cusk eel comes to feed inches from the camera, as a scientist marvels: "I've never seen that guy."

Looking on is Dr. Robert Ballard, the renowned oceanographer and marine archaeologist who is best known for discovering the wrecks of the Titanic, John F. Kennedy's PT-109 motorboat and other famous lost vessels. That's one scene in our exclusive clip of Alien Deep with Bob Ballard, a National Geographic Channel special that explores the secrets of the deep, from submerged volcanoes to mysterious species.

Dr. Ballard's adventures at sea began at age 17, aboard a Navy ship that was hit by a rogue wave. In the intervening five decades, he's collected some great stories. HuffPost Science sat down with him to probe the depths of his mind.

What does he consider his most important discovery? We'll give you a hint: it's not the Titanic.

Ballard says he's most proud of the giant tube worms (Riftia pachyptila) that were first described on a Galapagos expedition he took part in in 1977. The tube worms live around hydrothermal vents on the sea floor called "black smokers," and make their food without any sunlight to help with photosynthesis.

SCROLL DOWN FOR PHOTOS

Ballard has found or helped find several important shipwrecks, but he's not interested in going after all of the estimated 1 million wrecks in the ocean today. This is partly because the job requires a lot less ingenuity than it used to. Now, with various ancient maritime trade routes mapped out, his teams know where to look, and when something interesting is found he can get a live feed from the boat sent to his phone.

But for all the advances in ocean sciences he's been part of, Ballard still thinks there's much more work to be done. He notes that NASA's $2.5 billion Mars Curiosity Rover could fund explorations of U.S. waters for 100 years, and wonders why "we have better maps of Mars" than of U.S. offshore seabeds.

What does he see in his own future? “I want to discover as fast as possible,” Dr. Ballard says. “Because in my lifetime, I will not get the job done. It’ll take generations. So I’m trying to accelerate the rate of discovery. I’m selfish. I want to
see it before I die.”

But he's got some advice for the next generation of explorers: "Discovery," he says, "is easy. If you look somewhere nobody's ever looked, you're bound to find something."

Alien Deep with Bob Ballard airs Sunday, September 16, from 7 p.m. to 11 p.m. ET/PT and Monday, September 17, from 8 p.m. to 9 p.m. ET/PT, on the National Geographic Channel.

Loading Slideshow...
  • Galapagos Ridge, near Galapagos Islands, Pacific Ocean: Tube worms cling to a rock and catch chemicals from hydrothermal vents to feed the chemosynthetic bacteria they host. (Photo Credit: NOAA/ Webb Pinner)

  • Nautilus, Aegean Sea: Amphoreas on the ocean floor, a sign of a ship wreck. (Photo Credit: National Geographic Television)

  • Teahupoo, Tahiti: A surfer in a barrel of wave. (Photo Credit: National Geographic Television)

  • Mediterranean: An eel crosses a field of amphorea. (Photo Credit: NOAA/ Webb Pinner)

  • Strytan smectite cone, near Akureyri, Iceland: Divers use a remote camera to film warm alkaline vents - smectite cones. (Photo Credit: National Geographic Television)

  • Hanksville, Utah, United States: Cadets with the Civil Air Patrol participate in a Mars Simulation mission in the Utah desert. The desert habitat gives the cadets an idea for the challenges early explorers on Mars might face. (Photo Credit: National Geographic Television)

  • East Scotia Ridge, in the Southern Ocean SE of South America: "Hoff" crabs swarm over one another at a hydrothermal vent. (Photo Credit: National Oceanography Centre)

  • CGI IMAGE: The Pisces IV and V submersibles explore the underwater slopes of Mauna Kea. Submersible pilots Terry Kerby and Max Cremer dive the subs to gardens of deep sea corals as part of their second test dive in preparation for the upcoming dive to Loihi seamount. (Photo Credit: National Geographic Television)

  • Hanksville, UT - USA: Three research facilities for the cadets with the Civil Air Patrol participate in a Mars Simulation mission in the Utah desert. The desert habitat gives the cadets an idea for the challenges early explorers on Mars might face. (Photo Credit: National Geographic Television)

  • Greenbelt, MD: Buzz Aldrin at the Goddard Space Flight Center. (Photo Credit: National Geographic Television)

  • The Pacific Ocean off of the coast of Kona, Big Island, HI: Kona Blue Water Farms Aquapod floating on surface of the water. (Photo Credit: National Geographic Television)

  • Thingvellir National Park, Iceland: Divers at Mid-Atlantic Trench in Iceland. (Photo Credit: National Geographic Television)

  • Thingvellir National Park, Iceland: Silhouette of Bob Ballard snorkeling between the crack where the North American and Eurasian plates meet in Iceland. (Photo Credit: National Geographic Television)

  • Reykjanes Peninsula, Iceland: Dr. Bob Ballard at the Reykjanes Peninsula. (Photo Credit: National Geographic Television)

  • East Scotia Ridge, in the Southern Ocean SE of South America: A "Hoff" crab, a relative of the Yeti crab, climbs up a black smoker vent chimney at a hydrothermal vent site along the East Scotia Ridge., as sceen by the ROV Isis' camera. (Photo Credit: National Oceanography Centre)

  • Galapagos Ridge, near Galapagos Islands, Pacific Ocean: Tube worms cling to a rock and catch chemicals from hydrothermal vents to feed the chemosynthetic bacteria they host. (Photo Credit: NOAA/ Webb Pinner)

  • Thingvellir National Park, Iceland: Dr. Bob Ballard after snorkeling in the Mid-Atlantic Trench in Iceland. (Photo Credit: National Geographic Television)

  • East Scotia Ridge, in the Southern Ocean SE of South America: A black smoker hydrothermal vent expels superheated water, chemicals and metals that look like "smoke," at the East Scotia Ridge in Antarctica. (Photo Credit: National Oceanography Centre)