A catastrophic implosion likely led to the loss of the only scientific vehicle that could work at such extreme depths.
On Friday a deep-sea robotic vehicle named Nereusvanished under the weight of 6.2 miles (9,977 meters) of water in the western Pacific Ocean.
Surface debris—spotted the day after researchers on a support ship lost contact with the vehicle—suggested Nereus suffered a catastrophic implosion while exploring the Kermadec Trench northeast of New Zealand.
Owned and operated by the Woods Hole Oceanographic Institution (WHOI) in Woods Hole, Massachusetts, Nereus was the only scientific vehicle currently operating that could work at such extreme depths. Its loss has "certainly put a big rent in the works here," says Susan Avery, president and director of WHOI.
Nereus was lost 30 days into a 40-day expedition to explore the second deepest trench in the world. Scientists plan to finish their research tripwith the remaining tools available to them, including baited traps, an underwater elevator, and other instruments they can send over the side of the ship and subsequently recover.
Nereus was also scheduled for five or six more expeditions later this year, Avery says. Now, all of those projects will have to go back to the drawing board to see what can be salvaged from this loss.
Researchers on Nereus's support ship, the R.V. Thomas G. Thompson, had just used the vehicle to collect a sea cucumber on May 9 when their camera feeds went dark. This had happened before, WHOI spokesperson Ken Kostel wrote in a statement, and operators on the ship weren't particularly worried.
Then they also lost touch with a positioning system on Nereus that kept track of the vehicle's location in relation to the ship. Under such circumstances, the robot was programmed to wait a half hour so that the ship could be moved a safe distance away from its last known location, then drop the weights keeping it at the bottom so that it could surface.
Written By: Jane J. Lee
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