Deep-Sea Vehicle Nereus Lost 6 Miles Down


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.

Shattered Remains

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
continue to source article at


  1. This is not typically the kind of story that inspires debate, but I certainly related to it. The funds needed to engineer and build these subs is substantial and not easily replaced, yet the science they provide is exceptional. As an experienced diver I marvel at life in the limited depths even I can reach, barely 150 on a compressed-air dive, yet it does not even come remotely close to the incredible distance these machines can travel to. There is an surface atmosphere of pressure added every 33 feet you drop; people have no conception of the extraordinary pressures in the ocean depths. To put it graphically your body would end up the size of a basketball if you were down that far. With still so much to learn I hope Nereus can be replaced. We need research more than ever the way the climate is changing so quickly and every little bit of data is valuable. Maybe someone can find a rare religious artifact and give it a toss overboard near a deep trench so that funding would pour in for a new sub that could go retrieve it! One thing is for sure, religion has taught us bugger-all, nada, nothing, big fat zero about the deep ocean. Subs like these, however, have taught us there is a possibility that deeps vents originated life on earth. It is remarkable anything lives down there at all, yet look at science go. Build another one!

  2. I was hoping someone would publish some details on the various components of Nereus, with an explanation of which one actually imploded, and what would have happened to all the other bits. We see that often with aircraft accidents, why not here ?

  3. In reply to #2 by rod-the-farmer:

    I was hoping someone would publish some details on the various components of Nereus, with an explanation of which one actually imploded, and what would have happened to all the other bits. We see that often with aircraft accidents, why not here ?

    I was thinking the same thing. I would imagine there must be some kind of sensors to detect the stress on the components and to alert the people above when it seems like a catastrophic failure is imminent. It would be interesting to know if that is actually the case and if so why they think it may not have worked this time. My guess is that working at these depths is so unprecedented that it’s hard to always predict what will happen.

  4. There’s no doubt that science works, but maybe the engineering went wrong on this occasion ? A great shame IMO.

  5. There will no doubt be an investigation of the wreckage, but in addition to the pressures, there are other hazards down there:- rocks, wrecks, and hydrothermal vents hot enough to soften or melt the laminates these craft are made of.

  6. maybe GODZILLA is real and he ate it.
    sorry i just saw the movie.
    it just goes to show that there are places still on this earth that we still haven’t explored.
    the engineering for this kind of research similar to outer space is a risky place to research and its only through accidents like this that we may learn. and maybe think laterally to solve the problem.

Leave a Reply