Inner Space

A fair bit of my research is focused on deep-sea hydrothermal vents because that’s one of the places iron is, and bacteria that eat iron are what I study. Most of these sites are anywhere from around 3,000 to 9,000 feet deep, and some are closer to 15 or 16,000 feet. That’s a long way down. To get there we use deep-sea submersibles, which are basically mini-submarines. There are manned submarines and increasingly unmanned subs, or robots.

There was a nice story in the New York Times a few days ago about the future (or lack thereof) of manned exploration of the deep-sea It features the Hawaiian Undersea Research Lab (HURL), and the challenges they face in keeping their research submersible fleet going. I’ve been fortunate to work with HURL, and Terry Kerby who is the chief pilot there and keeps the whole operation running on a shoestring budget. Terry’s the kind of remarkable guy you would expect who makes his living diving a mile or more below the ocean surface. Shark wrangler is one of his past job descriptions.

There’s no one I’d rather having piloting a submersible with me in it, especially diving 1300 feet deep into the caldera of Loihi Seamount, one of the world’s most active undersea volcano’s. A couple of favorite Terry stories, are being in the caldera in Pisces V, one HURL’s submersibles, asking Terry about rumbling noise coming from the sonar, “Oh that’s a rock slide up above us”, was his calm reply. Another time, or maybe it was the same time, we were in the bottom of the caldera and pushing the 6 ton Pisces up against some rocks in an effort to reach some vent samples that were under an overhang, that I wanted to collect. After we finished sampling, Terry said, ‘let’s take a look at what’s above us’. We proceeded to fly up a rock face ten stories high that had no visible means of attachment to the surrounding walls.

Terry is not risk averse, but in years of running a submersible operation, HURL has an excellent safety record. Being good at what you do, and willing to take some calculated risks is essential to being a submersible pilot, an explorer, or a scientist. If folks like Terry, the group at HURL, and the other folks I know who run submersible programs were in charge of lots of other things we like to complain about because they are chronically inefficient, over budget, and risk averse, the world would be a more interesting and better place.


@3,500 ft below the surface in Pisces V, Terry Kerby, center, me on the left.

Nonetheless as a scientist I do face a dilemma. For much of the research we do, robots, instead of manned submersibles, have many advantages, chief among them are long bottom times, literally days, and the ability for multiple people to observe and make decisions about what samples to collect and what science should be done. When things are working well, robots offer a much greater capacity to see lots of things, collect lots of things, and conduct experiments on the seafloor. Most of the work I do now in the deep sea is with the remotely operated submersible Jason II run by the Woods Hole Oceanographic Institute. It would seem hard to go back to using a manned sub, which in the deep ocean, typically would only has 4 – 6 hours of bottom time out of every 24 hours.

The advantage of manned submersibles, however, is they are faster, you can see more, they are more maneuverable, and often they can handle larger payloads. If you need to find something quickly, or do something quickly on the seafloor, a manned submersible is the way to go. They can also work in rougher weather. The last expedition I was on we spent several days waiting for the seas to subside enough that we could launch Jason, while a manned submersible could have been in the water. Still, I wonder if we would have made the key discovery we did make, if we had been using a manned submersible. It would have depended who was on board on that particular dive.

The most recent scuttlebutt I heard about HURL was they are close to reaching the end of their ability to patch little pieces of money and projects together to remain viable for doing manned submersible work. They used to be funded by NOAA (National Oceanic and Atmospheric Administration), but that support dried up long ago. Now the plan is to do a final big expedition with the Chinese and then sell their subs to the China. Once again, at the leading edge of American science?

So I’ll end with my personal take on the value to having humans go to the inner space of the deep ocean floor to do things that robots can do as efficiently, although, surprisingly, not that much cheaper, than manned submersibles. Is it necessary to have the visceral experience of physically being on the bottom, and seeing things with your own eyes? After you’ve spent a few hours a mile deep in the cold, crushing pressure of the black abyss of inner space, the first glimmerings of blue you see as you return to the sunlit surface world will make you reflect spiritually on your own inner space. If there is not profound value in that, there is value in nothing.

David Emerson

About David Emerson

David Emerson is a professional scientist at the Bigelow Laboratory for Ocean Sciences who studies bacteria that live literally between a rock and a hard place. The views expressed here are his alone.