ONE-OF-A-KIND ALVIN SUBMERSIBLE IS 'EXTREME DEEP' HERO
"EXTREME DEEP: Mission to the Abyss" sponsored by John Hancock Financial Services and Discovery Channel features deep-sea creatures and amazing geological phenomena, robotic interactive displays and shipwrecks. But the real star of the blockbuster interactive exhibit is the deep-sea submersible with the humble name of Alvin.
Without development of and exploration by this highly unusual submarine, built in 1964, the ocean floor's wonders would have remained a mystery. Instead, they are presented in full detail by Evergreen Exhibitions in collaboration with Woods Hole Oceanographic Institution (WHOI). EXTREME DEEP brings to the surface the knowledge gleaned from Alvin's nearly 4,000 dives to the ocean floor. Other tools used to explore the deep ocean, including the remotely operated vehicle JASON and several autonomous underwater vehicles, are also featured in the exhibit.
EXTREME DEEP will travel to 15 cities across the nation on its five-year tour. The exhibit depicts the mysteries of the ocean's greatest depths. Newly discovered life forms, thermal vents and shipwrecks including Titanic are among the attractions in this deep-sea museum adventure, which puts the fruits of Alvin's many expeditions into the hands of museum visitors.
"None of this exhibit would be possible without Alvin," said David Gallo, Ph.D. in marine geology and director of special projects for Woods Hole Oceanographic Institution. "In the oceans, because of their great depth, observation requires sophisticated technology like that available on Alvin and other underwater vehicles. Using new computer technologies, we can gather information from the seafloor faster than ever before."
Used primarily for geophysical, geochemical, engineering and general purpose oceanography research, Alvin can dive to nearly three miles (4,500 meters) below the ocean's surface. Since its first dive in 1964, Alvin has made more dives--and discoveries--than any other submersible. In addition to exploring the Titanic and retrieving a sunken H-bomb, the sub made the most surprising discoveries of all: life at deep-sea vents over 2.5 miles (4 km) deep.
Alvin is 23 feet long, 12 feet high, 9 feet wide, weighs 17 tons and carries a 7-foot-diameter personnel sphere. Scientists spend, on average, eight hours inside this titanium sphere, where there's room for three. Built to withstand pressures greater than 10,000 pounds per square inch, the Alvin sphere has three conically shaped, cast acrylic windows called viewports which are 3.5 inches thick through which researchers explore the deep. The sub has made 3,500 dives to date and averages 175 to 200 dives each year. The vehicle is completely refurbished and updated every three years so none of the original pieces are still in use.
Before its first dive, Alvin's sphere passed 536 pressure tests. In the final test in 1964, testing pressure equal to a 9,676-foot dive, the test tank exploded, but the sphere remained intact. Today's sphere can safely dive to 14,764 feet (4,500 meters). Pilots on these dives, says Gallo, are at much greater risk every second than astronauts face in outer space.
"Any breach in the system will cause an implosion," says Gallo. The power of water pressure is demonstrated in the exhibit in astonishing detail through the display of several objects of various material which have been distorted, pulverized, shrunk and smashed flat when exposed to this enormous pressure.
One pilot and two additional scientists can fit into the 7-foot diameter personnel sphere. "It's about the same amount of room that three adults would share in a small car," said Gallo. EXTREME DEEP offers a full-size replica of this sphere which children and adults can experience. Once inside the sphere, visitors can manipulate replicas of actual instruments used by the scientists to dive and work on the ocean floor. Like the scientists, each museum visitor has a small viewport that offers actual video of Alvin's dive to the abyss.
Scientists use Alvin's robotic arms to collect samples and work with various tools during dives. The exhibit includes an actual Alvin arm which visitors can touch and manipulate, testing the dexterity of its claw. Visitors can also test their own skill in gathering lava rocks, clams and other items from the ocean floor using a scale robotic arm. Children of all ages will find this portion of the exhibit challenging and exhilarating as they test their hand-eye coordination looking through the deceptively small, four-inch viewport. It's not as easy as it looks!
EXTREME DEEP visitors will also encounter three-dimensional models of JASON and ABE, both capable of exploration as deep as 20,000 feet (6,000 meters). While Alvin takes scientists to the seafloor, JASON allows scientists to explore the seafloor from the surface via fiber optic cable using video cameras and other technologies. Autonomous vehicles like ABE and REMUS are programmed for independent operation on the seafloor from coastal waters to the deep sea, often for months at a time.
EXTREME DEEP, designed for ages 6 and older, introduces weather, geology, history, biology, chemistry, exploration and the critical role that technology plays in understanding our world and its future.