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A Place Like No Other

Adventures on the Seafloor: A Brief History of Alvin

Back in the 1950s, the National Academy of Sciences and National Research Council convened a symposium in Washington, D.C., to discuss ways to explore the ocean’s depths. Attending was physicist and oceanographer Allyn Vine, who made a notable argument for using submersibles operated and occupied by people: “I believe firmly that a good instrument can measure almost anything better than a person can if you know what you want to measure. … But people are so versatile; they can sense things to be done and can investigate problems. I find it difficult to imagine what kind of instrument should have been put on the Beagle instead of Charles Darwin.” Attendees were convinced, and thus Alvin was born.

Alvin the deep-ocean submersible

Operated by Woods Hole Oceanographic Institution, owned by the Navy and built by General Mills (yes, that General Mills), Alvin was one of the world’s first deep-ocean submersibles and today holds the title of the world’s oldest research submersible. It was named in honor of Allyn Vine and has made more than 4,600 dives, transporting about 2,800 unique Alvinauts to the seafloor.

In its 50-year history, Alvin has been responsible for the discovery of hundreds of new animal species and uncountable new microbial species. Noteworthy findings include a big red octopus called Benthoctopus sp.; a furry worm known as the “Pompeii worm” that can withstand the hottest temperatures of any animal; and an unusual-looking crab commonly called the “Yeti crab” for its large size, white color and long “fur” on its legs.

Alvin is capable of carrying two scientists and a pilot for a total of six to 10 hours, hovering in the water, navigating rugged topography or simply resting on the seafloor. It’s equipped with two robotic arms and high-intensity LED lights to illuminate the dark depths of the ocean, plus HD-quality video and still cameras to chronicle its findings.

Alvin’s history is full of exciting adventures, including a 1966 mission to locate a hydrogen bomb that dropped into the Mediterranean Sea after two U.S. Air Force planes collided. (It was a success.) It made 12 dives to survey the wreck of the Titanic, producing dramatic photographs of the world’s most famous shipwreck and garnering international attention. In 2000, Alvin discovered a bizarre Atlantic environment previously unknown to scientists: Called the “Lost City,” this deep-sea terrain was composed of strange geological structures and chemosynthetic communities produced when seawater reacts with mantle rock.

But perhaps one of the most extraordinary expeditions was the 1977 discovery and exploration of hydrothermal vent sites. Scientists took Alvin nearly 8,000 feet below the ocean’s surface on the East Pacific Rise near the Pacific Ocean’s Galapagos Islands. What they found astonished them and transformed our understanding of life as we knew it: Organisms were capable of living and thriving in these depths, despite the absence of sunlight.

Hydrothermal Vents. Image courtesy of the The National Oceanic and Atmospheric Administration.

Hydrothermal vents image courtesy of the NOAA

Scientists operating Alvin discovered large aggregations of never-before-seen clams, worms and mussels. And we’re not talking about your average supermarket shellfish—the giant white vent clams found in this habitat can reach up to a foot long. Other new species included six-foot-long red-and-white tubeworms (Riftia pachyptila) and blind shrimp (Rimicaris exoculata) with big spots of visual pigment on their backs—scientists hypothesize it’s used to detect faint radiation given off by the super-hot vents.

To give you an idea of what “super-hot” means: Hydrothermal fluid temperatures can reach 750 degrees Fahrenheit—sometimes more. Compared to hot springs and geysers, hydrothermal vents form when tectonic plates spread apart and hot magma heats the seawater circulating deep in the ocean’s crust. As the seawater warms and pressure rises, it starts to dissolve minerals and move toward the crust’s surface, where the minerals form chimney-like formations around the vent opening as they cool.

Alvin discovered these deep-sea formations along the Mid-Atlantic Ridge as well. Unlike the Pacific vents, these habitats lacked tubeworms but included thousands of shrimp swarming around the vents.

Today, Alvin’s at it again. It just underwent a $41-million upgrade to enhance its systems and is better than new, fully equipped to continue exploring our underwater world. With a staggering 95 percent of our oceans still unexplored, who knows what it will find in the years to come.


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