A process to extract metals from their ore with hydrogen could make deep-sea mining for valuable materials more sustainable than mining on land, a new study claims.

Swathes of the ocean floor are littered with nodules the size of tennis balls. These polymetallic nodules are comprised largely of manganese, with smaller amounts of nickel, copper and cobalt, as well as other elements. As the construction of solar power and electric vehicles booms, demand for these metals is increasing because they are vital components of batteries and wiring. But plans to mine for the polymetallic nodules are highly controversial because operations to collect them would potentially harm the deep-sea floor 鈥� one of the last pristine ecosystems on Earth.

Even so, some researchers suspect that deep-sea extraction will eventually take place. 鈥淚 think there is a good chance that someday people鈥� will mine the nodules,鈥� says at the Max Planck Institute for Sustainable Materials in Germany. 鈥淪o better to have a good process [for extracting metals] after mining than to have one more dirty process.鈥�

, a Canadian deep-sea mining company that has applied for a deep-sea mining permit from the Trump administration, to extract metals using a fossil fuel-based approach involving coke and methane. Its process involves placing the nodules first in a kiln and then an electric arc furnace 鈥� a greener alternative to a traditional blast furnace. Even so, the company says its approach will produce 4.9 kilograms of carbon dioxide emissions for every 1 kilogram of valuable metals.

Manzoor and his colleagues have found a way to lower these extraction-related emissions. Their system doesn鈥檛 involve a kiln. Instead, the nodules would be ground into smaller pellets and placed straight into an arc furnace that also contains hydrogen and argon gas. High-energy electrons flowing from an electrode in the furnace to the pellets would knock electrons off the molecules of hydrogen gas, forming a plasma that can be heated up to temperatures exceeding 1700掳C.

The hydrogen ions in the plasma then react with the oxygen in the pellets, stripping the oxides away from the alloy and leaving pure metal behind. Besides water, the only by-products are manganese compounds that can be used for making batteries and steel.

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If the hydrogen gas used in the furnace is 鈥済reen鈥� 鈥� meaning it is produced by splitting water with electricity from renewable sources 鈥� and the electricity to run the furnace is generated from renewable sources, the process should emit no CO2, according to the researchers. Today, the vast majority of hydrogen is produced using fossil fuels.

Metals like manganese are found on land as well as on the seafloor, but at concentrations about 10 times lower. Mining them on land involves moving large amounts of earth, and extracting the metal from the ore often relies on sulphuric acid. The process can result in razed rainforests and polluted rivers.

However, land-based mining could be better regulated to prevent environmental destruction, and the smelting of the metals could be done with green hydrogen and renewable electricity rather than fossil fuels, argues at Pforzheim University in Germany. At that point, vacuuming up nodules from the seabed wouldn鈥檛 necessarily be more sustainable.

鈥淲e do not see any fundamental advantage for deep-sea mining in terms of carbon footprint,鈥� he says. 鈥淭he sustainability of deep-sea mining fails because of the threat it poses to the biodiversity of deep-sea flora and fauna.鈥�

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But the process that Manzoor and his colleagues have developed could help deep-sea mining become more economically viable, according to at Imperial College London.

鈥淚n addressing how you would do the extraction metallurgy downstream of actually picking it up off the seabed, you may be able to then open up the business case and the environmental case to make that attractive,鈥� he says.

Manzoor stresses that the research isn鈥檛 meant to advocate for deep-sea mining, and the environmental impacts should be fully investigated.

Salt water covers seven-tenths of Earth鈥檚 surface and is where life began. So it is no surprise that our oceans are home to a wide diversity of creatures of all shapes, colours and evolutionary strategies.

Marine biologist and writer Helen Scales鈥檚 latest book, , takes us on a journey through these vast underwater landscapes and their inhabitants via 140 photographs and illustrations 鈥� ranging from fine ceramic art to scientific drawings.

The art is as diverse as the ocean life it represents. And Scales tells us as much about the artists as the sea life in a fusion of marine biology and art history.

鈥淚 find it fascinating to see the sea through the eyes of artists and craftspeople,鈥� says Scales. 鈥淭hey capture a vivid sense of what life is like beneath the waves.鈥�

Cultures throughout history have been fascinated with ocean life. The artworks here are (pictured from top): a lithograph of a strawberry squid (Histioteuthis heteropsis) from 1851; a hand-coloured engraving of a pilchard (Argentina carolina), 1743; an 1830 woodblock print from Japan featuring crabs; an 1888 illustration of a siphonophore (Forskalia tholoides); a Mycenaean jar depicting an octopus, from around 1200-1100 BC; a ceramic vessel from Peru in the form of a lobster, 4th to 6th century AD; pictured with a Nazca bowl, also from Peru, showing a crab, made between the 2nd and 4th centuries AD.

Ocean Art is published in the UK on 1 August and in the US on 26 September.

Spider-like creatures living near methane seeps on the seafloor appear to cultivate and consume microbial species on their bodies that feed on the energy-rich gas. This expands the set of organisms known to rely on symbiotic relationships with microbes to live in these otherworldly environments.

at Occidental College in California and her colleagues collected sea spiders 鈥� marine arthropods named for their resemblance to arachnids 鈥� living near three different methane seeps in the Pacific Ocean. They found three previously unknown species from the sea spider genus Sericosura that appear to be abundant only near these gas seeps.

Other types of sea spiders that don鈥檛 live near seeps largely eat other invertebrates. But the researchers found the new sea spiders appear to get most of their nutrition by eating a distinctive set of bacterial species that live on their bodies. These bacteria harvest energy by metabolising methane and methanol coming from the seeps, energy that would otherwise be inaccessible to the sea spiders.

The researchers found the bacteria were confined to the spiders鈥� exoskeletons like a 鈥渕icrobial fur coat鈥�, growing in what Goffredi describes as 鈥渧olcano-like鈥� clusters. The layers of bacterial growth also had markings like lawnmower tracks where the spiders may have munched on them using their hard 鈥渓ips鈥� and three tiny teeth.

To confirm the sea spiders really were eating the bacteria, the researchers also used a radioactive labelling technique to track how the carbon in methane was consumed by the sea spiders in the lab. 鈥淲e watched that methane go into the microbes that are on the surface of the spiders, and then we watched that carbon molecule move into the tissues of the spider,鈥� says Goffredi.

The researchers don鈥檛 think the sea spiders are just eating whatever happens to grow on their exoskeletons. Because the species that live on the exoskeletons are distinct from what鈥檚 generally found in the environment, it suggests some kind of selection process is at play, says Goffredi. 鈥淭he spiders are definitely cultivating and farming a very special type of community.鈥�

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Sea spiders wouldn鈥檛 be the first organisms to farm microbes to access chemical energy. 鈥淓ach time we look [at ecosystems around methane seeps], we鈥檙e finding this more and more,鈥� says at Temple University in Pennsylvania. He worked with Goffredi on an that found a similar symbiosis in tube worms. The abundance of life found near the seeps 鈥渋s being fuelled by methane and other chemicals and not by the energy of the sun. That鈥檚 pretty amazing,鈥� he says.

Cordes points out that the bacteria also stand to gain by riding along on the sea spiders鈥� bodies. Not unlike cows on a ranch, they gain protection and access to better pastures. For instance, if a methane seep shifts to a different part of the seafloor, the sea spiders could move the bacteria to the new source. 鈥淭he sea spiders are keeping them in the perfect habitat,鈥� he says.

These eerily beautiful images show animals born at Europe鈥檚 largest jelly-fish breeding facility: Jellyfish Farm, in K眉nzell, Germany 鈥� hundreds of kilometres from any ocean.

Photographers used macro lenses and studio flashes to capture the images, but they were most concerned with the positioning of the jellyfish, which sink to the bottom of a normal aquarium and thus wouldn鈥檛 be photographable. The animals needed a 鈥渏ellyfish kreisel鈥�, or gyroscope, to create water movement, without which they can鈥檛 swim or feed.

Jellyfish drift 鈥渂etween being an environmental threat and a source of sustainable innovation鈥�, say the Kochs as part of their project. The number of blooms is increasing as oceans heat up and pollution and overfishing increase, with dire consequences for ecosystems and economies.

But jellyfish also present great opportunities: as animal feed, fertilisers or human superfoods, thanks to the anti-inflammatory and immunologically important biochemicals they contain. Their mucus can also create a biofilter to stop plastics from reaching the sea.

Pacific compass jellyfish (Chrysaora fuscescens) are shown in the main picture. They will be shipped to zoos, aquariums and research institutions. Below this, a gyroscope provides an ocean-like vortex for moon jellyfish (Aurelia aurita). Pictured above, a pipette contains mangrove jellyfish (Cassiopea xamachana).

As adults, they will live on the seafloor, their tentacles pointing to sunlight, helping single-celled algae there conduct photosynthesis. The image above shows jellyfish specimens being checked before dispatch.

听

A colossal squid 鈥� the largest invertebrate on the planet 鈥� has been filmed alive in its wild habitat for the first time.

For decades, the Kraken-like colossal squid () was more myth than reality: scientists had only a vague sense of its appearance from fragments of its remains found in the stomachs of the whales that eat the molluscs. In fact, it was through those remains that the species was officially described by zoologists in 1925.

Finally, in 1981, fishers in Antarctica accidentally reeled up a live colossal squid in their fishing nets. Since then, the animals have sometimes been killed as fishing bycatch, or have washed ashore dead.

Last month, a vessel from the , a US-based non-profit organisation, was surveying the Southern Ocean near the South Sandwich Islands and live-streaming the footage from their remotely controlled deep-sea cameras, when an online viewer flagged that they might have just filmed a colossal squid.

Acting on the tip, the researchers sent the high-resolution footage to independent squid experts. The experts confirmed that the online viewer鈥檚 hunch was correct: the squid had distinctive hooks along the suckers on its eight arms, which are a hallmark of the colossal squid. It was roaming at 600 metres under the water鈥檚 surface.

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While colossal squids are thought to grow up to 7 metres in length and 500 kilograms in weight, the squid caught on camera was a mere 30 centimetres in length: a baby.

鈥淚t鈥檚 amazing that every time we go down into the deep sea, we find something new and exciting,鈥� says of the Schmidt Ocean Institute.

A colossal squid in its natural habitat in 2023 by researchers from another US-based organisation, 鈥� but the sighting couldn鈥檛 be confirmed because the footage was too low in quality. The new squid recording might suggest the 2023 footage really does capture a colossal squid. 鈥淚t鈥檚 the same size, same colour, similar depths, both in the Southern Ocean,鈥� says at Kolossal, who is still awaiting further confirmation.

However, there is as yet no footage of an adult colossal squid in the wild, and the lives of these gigantic invertebrates are still mysterious, says , formerly at Auckland University of Technology, New Zealand, who coined the name 鈥渃olossal squid鈥� in the early 2000s. He once touted the animals as 鈥渟eriously evil denizens of the deep鈥� but is now convinced they are more like 鈥済iant gelatinous ticks, simply blobbing around in the water column near the seabed鈥�.