Mining historic shipwrecks for lead and other old things from the bottom of the sea. Also, Robots! Weekly Salvage: November 4, 2019

Transcript available below.

Somehow we managed to do a whole episode without 3D printing or deep-sea mining. But don’t worry, we’ve got robots, so we’re still on brand, here. 

Welcome to the Weekly Salvage.

If you want to find dark matter in the universe, you have to start by diving ancient shipwrecks. The most sensitive particle detectors need to be shielded from radiation, including the radiation emitted by their own radiation shields. Centuries-old refined lead from the bottom of the sea has incredibly low levels of intrinsic radioactivity, making it an ideal material to shield the equipment trying to pierce the deepest mysteries of the universe. And, of course, any material made after July 16, 1945 is just a bit more radioactive than it should be. 

That’s not the only way maritime history is helping us understand the universe. Down in Australia, the 60-year-old diaries of a senior SCUBA diver are being used to reconstruct the state of Australia’s waters in the 1950s. Clarrie Lawler’s notes have so far help document the proliferation of weedy sea dragons as well as reveal a previously undocumented species of sea urchin. 

All of which should serve as a reminder to always take good notes. You never know what information will be critically important to future generations.

Two years after a deadly collision that ended the lives of 10 sailors, the guided-missile destroyer USS John S. McCain has returned to sea after extensive repairs. The ship was famously moved out of sight during a presidential visit to the naval base because Donald Trump is a small, sad little man. 

Researchers in Japan discovered a new species of Amphipod living inside the gills of a whale shark. However, they were unable to determine if these amphipods are commensal with whale sharks or simply opportunistically feeding off organic matter in the shark’s gills. They’ll just have to vacuum more whale sharks to find out. 

One the heels of a successful voyage back to the wreck of the Titanic, submarine-builder OceanGate is constructing two additional 6000-meter-rated submarines. As publicly funded submersible programs continue to face budget-shortfalls, tools like these will be essential to maintaining a presence in the deep ocean. Off course, more forward-thinking nations like India and China are investing heavily in deep-ocean research, so we are likely witnessing the end of American dominance in deep-sea exploration. 

Robots are so good, you guys. I don’t know if you can tell from the context, but I’m kind of a huge fan of ROVs, the remotely operated vehicles that are the workhorses of deep-ocean exploration. But ROVs are generally deployed at depths beyond what humans and our flabby, meat-filled bodies can handle. In Remotely operated vehicles as alternatives to snorkelers for video-based marine research, researchers compared the performance of small ROVs operating in shallow waters to trained snorkelers. 

And the results are bad news for those of you not on Team Skynet. 

The mini-ROV, a Blue Robotics BlueROV2, outperformed snorkelers on every metric. It recorded higher fish abundance and biodiversity, did not noticeably alter fish behavior, and could stay in the water longer without needing coffee and a sandwich. Presumably it also didn’t pee in its wetsuit. 

ROVs aren’t without their own challenges, too. My team has published two sets of guidelines for minimizing the impact of small, low-cost robotics in marine ecosystems, including one for invasive species and another for interactions with marine mammals.

Thank you for watching. Don’t forget to click like, hit subscribe, and ring that ships bell. 

These videos are supported by my fans on Patreon, but they’re only a small part of what my Patrons support. In addition to keeping you up to date on the state of the ocean, we’re also developing open-source tools to help researchers, explorers, and citizen scientists better measure and understand our changing oceans. You can even build your own open-source CTD. 

So send a few bucks my way on Patreon. We’ve got stickers for supporters and hardware if you want to start hacking the ocean with us.