Want to know what early or extraterrestrial life might look like? You might try looking at Earth’s extremes: the coldest, highest, and deepest places on our planet. One unmanned research vehicle just tried the last of these strategies, and took samples from a hydrothermal vent plume 16,000 feet under the sea–about 2,000 feet deeper than the previous record-holding vent.
A research team led by Woods Hole Oceanographic Institution (WHOI) and including scientists at NASA’s Jet Propulsion Laboratory studied three hydrothermal vents, found along an underwater ridge in the Caribbean called the Mid-Cayman Rise. They published their findings yesterday in The Proceedings of the National Academy of Sciences.
Hydrothermal vents are usually found in spots where the Earth’s tectonic are moving away from each other, creating a weird zone of raw chemistry. A mixture of hot vent fluids and cold deep-ocean water form plumes, which can contain dissolved chemicals, minerals, and microbes. Instead of searching the entire 60-mile-long ridge with the vehicle, the team scouted for chemicals from the plume to zero-in on the vents.
“Every time you get a hydrothermal system, it’s wet and hot, and you get water and rocks interacting. Wherever this happens on the seafloor, life takes advantage,” said geophysicist Chris German of the Woods Hole Oceanographic Institute. “Every time you find seawater interacting with volcanic rock, there’s weird and wonderful life associated with it.” [Wired]
The bottom of the sea is a strange and marvelous frontier, as we were reminded last week by the discovery of the first known animals to live without oxygen. Today a team of British researchers say their undersea robotic explorers have found something new down in the depths of the Caribbean Sea: the deepest hydrothermal vents ever seen.
The black smokers, named for how they spew out an iron sulfide compound that’s black, sit 3.1 miles deep in the Cayman Trough in the Caribbean [FoxNews]. They beat out the previous record holders, which were located 2.6 miles below the surface in the middle of the Atlantic Ocean. As the National Oceanography Centre team sailed across the sea in its research vessel, the James Cook, the scientists deployed their robot explorers down to the inhospitable depths. One, called Autosub6000, mapped the seafloor while another, HyBIS, carried high-resolution cameras to capture these images.
After five years of research and three months of testing off the islands of Hawaii, scientists say the first underwater robot explorers powered solely by the ocean are ready for use. So far, all vehicles exploring the depths of the oceans have faced the possibility of running out of fuel, which made scientists wonder if there was any way that the ocean itself could power the vehicle. The answer came in the form of the Sounding Oceanographic Langrangrian Observer Thermal RECharging vehicle (or SOLO-TREC, for short)–a vehicle driven entirely by the natural temperature differences found in the ocean.
The vehicle, a joint project involving NASA, the U.S. Navy, the Scripps Institution of Oceanography, and the University of California at San Diego, completed its testing phase successfully, and scientists hope it can soon be deployed for research projects around the world. Researchers say this technology breakthrough could usher in a new generation of autonomous underwater vehicles capable of virtually indefinite ocean monitoring for climate and marine animal studies, exploration and surveillance [PhysOrg].
NASA’s Jack Jones says the fact that the robot just keeps going and going, like an aquatic Energizer bunny, brings humanity a little closer to an impossible dream: “People have long dreamed of a machine that produces more energy than it consumes and runs indefinitely…. While not a true perpetual motion machine, since we actually consume some environmental energy, the prototype system demonstrated by [NASA's Jet Propulsion Laboratory] and its partners can continuously monitor the ocean without a limit on its lifetime imposed by energy supply” [CNET].
A pioneering deep-sea robot, which could function unmanned and untethered to a surface ship, was lost at sea this week. The loss of the 15-year-old Autonomous Benthic Explorer, or ABE, comes as a blow to scientists who study the ocean’s floor. ABE could stay under water for an entire day; it ventured into some of the most remote and risky places on earth, making detailed maps of mid-ocean ridges and was the first autonomous vehicle to locate hydrothermal vents [The Boston Globe]. That’s why it earned a spot on Wired magazine’s list of “The 50 Best Robots Ever.”
ABE was on its 222nd research dive, studying a hydrothermal vent it had discovered off the coast of Chile on the Pacific floor, when all contact was lost with its surface vessel Melville. Scientists suspect that one of the glass spheres that helped keep ABE buoyant imploded. Scientists at the Woods Hole Oceanographic Institution, who designed and built the $1 million vehicle, believe that this implosion–almost two miles undersea and under pressure of more than two tons per square inch-would have caused other spheres in ABE to implode, destroying on-board systems and leaving the robot stranded at the bottom of the ocean floor.
It’s a robot that could change the way scientists gather data from underwater sources. Researchers from the Monterey Bay Aquarium Research Institute (MBARI) in California have developed a new autonomous underwater vehicle (AUV), and like other AUVs this sophisticated robot can slip under the waves, sweep the ocean floor, collect data, and perform programmed tasks. But the “Gulper” goes one step further–it doesn’t just follow its program, it can also make decisions on its own, and can plan its own route, avoiding hazardous currents and obstacles [BBC].
Explaining how the robot functions, Kim Fulton-Bennett from MBARI said: “We tell it, ‘here’s the range of tasks that we want you to perform’, and it goes off and assesses what is happening in the ocean, making decisions about how much of the range it will cover to get back the data we want” [BBC]. The ocean-going bot has also been described as “a microbiology laboratory in a can,” because it can analyze some samples in situ. The ‘ecogenomic sensor’, which is packed into a roughly 1-metre-long canister, can test for proteins released by microorganisms and even run DNA tests match DNA to determine which species are present [Nature News]. Findings can instantly be relayed to the shore, saving scientists the cumbersome task of transferring samples from site to lab.
Robotic explorers on Mars get a lot of veneration for their daring feats, as well they should–but let’s not neglect the robots that are busy exploring the most inaccessible regions of our own planet. On Sunday, a robot submarine known as Nereus dove to a depth of 6.8 miles to investigate the Mariana Trench in the western Pacific Ocean. Nereus descended all the way to the deepest cranny of the trench, a spot known as the Challenger Deep, and spent more than 10 hours making observations in a spot that is deeper than Mount Everest is high.
For the expedition, the team had to build a new breed of remotely-operated submarine … which is capable of going deeper than any other while still filming and collecting samples. Sunday’s dive makes it the world’s deepest-diving vehicle [currently in operation], and the first vehicle to explore the Mariana Trench since 1998 [New Scientist]. So far, researchers have released only a single image (pictured), showing Nereus’s robotic arm scooping up sediment.