Smack dab between Australia and South America, the US National Oceanic and Atmospheric Administration (NOAA) research vessel Rainier is currently on a mission to map more than 8,000 square nautical miles of the Pacific seafloor in search of critical mineral deposits. But it isn’t doing it alone; f or a month starting this week, it will deploy two oblong neon submersibles as the project’s special agents, sending them nearly 6,000 meters down to hop along the seafloor.  The submersibles, built by the young company Orpheus Ocean, are designed to explore just this environment: a squelchy substrate that teems with life of all kinds, from tiny microbes to worms and snails, along with egg-size “nodules” of metals—such as copper, cobalt, nickel, and manganese—that are crucial for technologies worldwide.   Scientists and companies have long sought to probe the deep sea and bring such treasures to the surface. Orpheus, which spun off from the Woods Hole Oceanographic Institution (WHOI) in 2024, could be well positioned to make those possibilities a lot more economical. The company has designed its vehicles on a simple philosophy: “deep for cheap,” says Jake Russell, Orpheus’s cofounder and CEO, who is a chemist by training. The vehicles cost a couple of hundred thousand dollars each to build, whereas existing options can range from $5 million to $10 million. And unlike most autonomous ocean vehicles, they can push into the seafloor and capture cores of sediment—and the creatures within.  Orpheus’s engineers have been tinkering with their deep-sea designs for years, much of the work taking place at WHOI and in collaboration with NOAA and the National Aeronautics and Space Administration. Its prototype vehicles were rated capable of diving to 11,000 meters—the deepest part of the Mariana Trench. They’ve completed two commercial deployments, but this new expedition marks the submersibles’ biggest test yet: operating over large ranges for multiple weeks and with multiple instruments at play. Using Rainier as their home base on the ocean’s surface, the vehicles will swim out for 10 kilometers at a time, taking one high-resolution image every second and up to eight physical samples from the seafloor apiece. If all goes well, the test could help establish the vehicles as a tool for government agencies, scientists, and companies that hope to probe the vastly understudied deep sea and the resources it holds. And while they’re not the only option on the market, Orpheus hopes their size and low building cost will soon make them one of the most accessible.  At present, to reach these depths scientists must wait for time on a limited and expensive set of submersibles owned by government agencies and research institutes. That formula lends itself better to capturing snapshots of the deep sea than it does to probing its interconnected ecological and biogeochemical systems. “A lot of this region that we’re surveying … has really never been explored in any kind of detail,” says Russell. “Anything we see is going to be new to NOAA and new to science.” A sediment specialist The Orpheus subs are classified as autonomous underwater vehicles (AUVs), which operate on a mix of preprogrammed commands and live decision-making and without being tethered to a ship. But unlike traditional AUVs engineered for long-distance, high-speed gliding, these submersibles are short and stout with little legs—better for making soft landings on the seafloor and then pushing into the mud to suck out sediment cores for scientists. When they do land, the submersibles can lift off the surface, thrust a few feet, and settle once more in a “hopping” fashion. Their bodies are made mostly of a buoyant material known as syntactic foam, with the important electronics encased in a thick sphere of glass. The same kind of foam, which is interspersed with hollow microspheres of glass to prevent it from collapsing under high pressures, went to the deep in the vehicle that carried the filmmaker James Cameron to the Mariana Trench in 2012; he even donated leftover material for use in earlier Orpheus prototypes.  At less than two meters in length and under 600 pounds (270 kilograms), Russell says the Orpheus robots are the smallest—and correspondingly the least expensive—ocean vehicles on the market capable of descending to 6,000 meters. They’re designed to populate future fleets of robotic explorers. The approach stems from a fundamental challenge, says Victoria Orphan, a geobiologist at the California Institute of Technology, who has previously worked with an Orpheus vehicle on a science campaign: “Anytime you do things in the deep ocean, you always run this risk, when you put something over the side [of a ship], that it might not come back.” With existing fleets of large, expensive vessels operated by groups like NOAA, WHOI, and the Monterey Bay Aquarium Research Institute (MBARI), losing a vehicle can be disastrous, not least because scientists must already compete for their limited time. In the spring of 2024, Orphan and her colleagues put an Orpheus sub through its paces during an expedition to study deep-sea methane seeps off the coast of Alaska’s Aleutian Islands. They hoped to use the vehicle to create maps of the area before the team sent down a human-crewed submersible called Alvin to study specific areas—and the microorganisms and animals that live there—in more detail.  But as with any sort of new type of technology, “there’s always growing pains,” recalls Orphan. Frigid temperatures and steep topography added unseen challenges, and it took the full three weeks for the sub to get high-resolution photographs of the seeps.  The setback didn’t dull Orphan’s excitement about the potential of these machines. “There’s a lot of real, unknown science right at that interface between the sediment and the ocean surface,” she says. “The Orpheus-type class of instrument, with the right kinds of sensors and samplers, could be a very enabling tool.” Russell envisions pairing the vehicles with specially designed payloads that can sense the heat of chemical seeps and detect plumes of sediment, DNA shed from ocean life-forms, or the magnetic tug of buried cables.  The vehicles are the “the best of both worlds,” says Andrew Sweetman, a deep-sea ecologist at the Scottish Association for Marine Science, who has not worked with Orpheus. While they can roam large areas like an AUV, they can also carry out precise sampling maneuvers like a remotely operated vehicle (ROV), a robot connected to a ship via cables that fulfills real-time human commands. In addition to the low price tag, says Sweetman, the small size of the vessels means they don’t require a large research vessel to ferry them out to sea. That might make exploration more accessible for smaller or poorer countries without such ships, he says: “It will, in a way, help democratize deep-sea science.” He imagines using the sediment cores the submersibles gather to probe how seafloor-dwelling animals cycle nutrients—a crucial element of the ocean’s role as a carbon sink.  The mining push  As much as smaller, cheaper ocean vehicles have caught scientists’ eye, they have also piqued the interest of companies. Russell says inquiries come in weekly from businesses involved in deep-sea mining, defense, offshore wind, telecommunication, and oil and gas. He notes that Orpheus is merely a “service provider,” helping collect data where needed but not making decisions about how to use the seafloor. And he says that better data—such as information on the shape of the seafloor, the sediment quality, and the presence of life—also “raises the bars” that governments and regulators are only beginning to set. But many scientists are far from eager about the growing push for seabed mining, which an executive order from President Donald Trump stoked further last week by mandating that the US government rapidly develop mineral exploration and processing. And earlier last month, the administration announced the creation of a new government office: the Marine Minerals Administration.  A view of an Orpheus vehicle from below.ORPHEUS OCEAN Given the current dearth of information on the deep sea, says Sweetman, “I think the push for deep-sea mining is happening way too fast.” And deep-sea communities are “probably the most stable environment on our planet,” adds Orphan. “The organisms that live there are really not adapted to a lot of disturbance, and it takes a really, really long time for them to recover, if at all.” One mining method that governments and companies propose involves a machine that essentially operates like a giant bulldozer, trawling the seafloor, sucking up a trail of material, and leaving scar marks and sediment plumes in its wake. Brett Hobson, an ocean engineer at MBARI, says that Orpheus-like technology might enable companies to “take samples in a more surgical way, instead of just grossly scooping everything up off the seafloor and filtering through it.” Hobson, who has run MBARI’s work on ocean vehicles for decades, also notes that Orpheus submersibles won’t be the only option available. Companies and government agencies—including those in Norway, France, Japan, China, and the UK—are developing similar deep-sea vehicles, he says: “What we really need [as] a society is just more of these systems out there.”  As Orpheus’s neon vehicles plunge into the Pacific over the next few weeks, their readiness for future scientific and resource surveys should become clearer. Each time they dive, they will get a little bit more data—“just the smallest of postage stamps of our planet,” says Orphan. “There’s still so much to learn.” ...read more read less