In January 1980, the WHOI-operated submersible Alvin made its 1,000th dive to the seafloor during an expedition to the Galapagos Rift. To keep the submersible in prime condition, Alvin recently completed a three-year overhaul that will enhance its diving capabilities. New features include larger viewports, more interior space for the vehicle's pilot and two passengers, and a 3-inch-thick titanium personnel sphere that will eventually allow for exploration beyond its current 2.8-mile depth rating. When Alvin returns to work in the fall of 2013, it will be for the submersible's 4,665th dive.
(Photo courtesy of Woods Hole Oceanographic Institution Archives.)