The fossil — the remains of a creature called Arthropleura — dates from the Carboniferous Period, about 326 million years ago, over 100 million years before the Age of Dinosaurs. The fossil reveals that Arthropleura was the largest-known invertebrate animal of all time, larger than the ancient sea scorpions that were the previous record holders.

The specimen, found on a Northumberland beach about 40 miles north of Newcastle, is made up of multiple articulated exoskeleton segments, broadly similar in form to modern millipedes. It is just the third such fossil ever found. It is also the oldest and largest: the segment is about 75 centimetres long, while the original creature is estimated to have measured around 2.7 metres long and weighed around 50 kilograms. The results are reported in the Journal of the Geological Society.

The fossil was discovered in January 2018 in a large block of sandstone that had fallen from a cliff to the beach at Howick Bay in Northumberland. “It was a complete fluke of a discovery,” said Dr Neil Davies from Cambridge’s Department of Earth Sciences, the paper’s lead author. “The way the boulder had fallen, it had cracked open and perfectly exposed the fossil, which one of our former PhD students happened to spot when walking by.”

Unlike the cool and wet weather associated with the region today, Northumberland had a more tropical climate in the Carboniferous Period, when Great Britain lay near the Equator. Invertebrates and early amphibians lived off the scattered vegetation around a series of creeks and rivers. The specimen identified by the researchers was found in a fossilised river channel: it was likely a moulted segment of the Arthropleura’s exoskeleton that filled with sand, preserving it for hundreds of millions of years.

The fossil was extracted in May 2018 with permission from Natural England and the landowners, the Howick Estate. “It was an incredibly exciting find, but the fossil is so large it took four of us to carry it up the cliff face,” said Davies.

The fossil was brought back to Cambridge so that it could be examined in detail. It was compared with all previous records and revealed new information about the animal’s habitat and evolution. The animal can be seen to have only existed in places that were once located at the Equator, such as Great Britain during the Carboniferous. Previous reconstructions have suggested that the animal lived in coal swamps, but this specimen showed Arthropleura preferred open woodland habitats near the coast.

There are only two other known Arthropleura fossils, both from Germany, and both much smaller than the new specimen. Although this is the largest Arthropleura fossil skeleton ever found, there is still much to learn about these creatures. “Finding these giant millipede fossils is rare, because once they died, their bodies tend to disarticulate, so it’s likely that the fossil is a moulted carapace that the animal shed as it grew,” said Davies. “We have not yet found a fossilised head, so it’s difficult to know everything about them.”

The great size of Arthropleura has previously been attributed to a peak in atmospheric oxygen during the late Carboniferous and Permian periods, but because the new fossil comes from rocks deposited before this peak, it shows that oxygen cannot be the only explanation.

The researchers believe that to get to such a large size, Arthropleura must have had a high-nutrient diet. “While we can’t know for sure what they ate, there were plenty of nutritious nuts and seeds available in the leaf litter at the time, and they may even have been predators that fed off other invertebrates and even small vertebrates such as amphibians,” said Davies.

Arthropleura animals crawled around Earth’s equatorial region for around 45 million years, before going extinct during the Permian period. The cause of their extinction is uncertain, but could be due to global warming that made the climate too dry for them to survive, or to the rise of reptiles, who out-competed them for food and soon dominated the same habitats.

The fossil will go on public display at Cambridge’s Sedgwick Museum in the New Year.

Neil Davies is a Fellow of Churchill College, Cambridge. The research was supported in part by the Natural Environment Research Council.

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Materials provided by University of Cambridge. Original written by Sarah Collins. The original text of this story is licensed under a Creative Commons License. Note: Content may be edited for style and length.

These snowballs — or as we know them, comets — go through a colourful metamorphosis as they cross the sky, with many comets’ heads turning a radiant green colour that gets brighter as they approach the Sun.

But strangely, this green shade disappears before it reaches the one or two tails trailing behind the comet.

Astronomers, scientists and chemists have been puzzled by this mystery for almost a century. In the 1930s, physicist Gerhard Herzberg theorised the phenomenon was due to sunlight destroying diatomic carbon (also known as dicarbon or C₂), a chemical created from the interaction between sunlight and organic matter on the comet’s head — but as dicarbon isn’t stable, this theory has been hard to test.

A new UNSW Sydney-led study, published today in Proceedings of the National Academy of Sciences (PNAS), has finally found a way to test this chemical reaction in a laboratory — and in doing so, has proven this 90-year-old theory correct.

“We’ve proven the mechanism by which dicarbon is broken up by sunlight,” says Timothy Schmidt, a chemistry professor at UNSW Science and senior author of the study.

“This explains why the green coma — the fuzzy layer of gas and dust surrounding the nucleus — shrinks as a comet gets closer to the Sun, and also why the tail of the comet isn’t green.”

The key player at the centre of the mystery, dicarbon, is both highly reactive and responsible for giving many comets their green colour. It’s made up of two carbon atoms stuck together and can only be found in extremely energetic or low oxygen environments like stars, comets and the interstellar medium.

Dicarbon doesn’t exist on comets until they get close to the Sun. As the Sun starts to warm the comet up, the organic matter living on the icy nucleus evaporates and moves to the coma. Sunlight then breaks up these larger organic molecules, creating dicarbon.

The UNSW-led team have now shown that as the comet gets even closer to the Sun, the extreme UV radiation breaks apart the dicarbon molecules it recently created in a process called ‘photodissociation’. This process destroys the dicarbon before it can move far from the nucleus, causing the green coma to get brighter and shrink — and making sure the green tinge never makes it into the tail.

This is the first time this chemical interaction has been studied here on Earth.

“I find incredible that someone in the 1930s thought this is probably what’s happening, down to the level of detail of the mechanism of how it was happening, and then 90 years later, we find out it is what’s happening,” says Ms Jasmin Borsovszky, lead author of the study and former UNSW Science Honours student.

“Herzberg was an incredible physicist and went on to win a Nobel Prize for Chemistry in the 1970s. It’s pretty exciting to be able to prove one of the things that he theorised.”

Prof. Schmidt, who has been studying dicarbon for 15 years, says the findings help us better understand both dicarbon and comets.

“Dicarbon comes from the breakup of larger organic molecules frozen into the nucleus of the comet — the sort of molecules that are the ingredients of life,” he says.

“By understanding its lifetime and destruction, we can better understand how much organic material is evaporating off comets. Discoveries like these might one day help us solve other space mysteries.”

A laser show like no other

To solve this puzzle, the team needed to recreate the same galactic chemical process in a controlled environment on Earth.

They pulled this off with the help of a vacuum chamber, a lot of lasers, and one powerful cosmic reaction.

“First we had to make this molecule which is too reactive to store in a bottle,” says Prof. Schmidt. “It’s not something we could buy from the shops.

“We did this by taking a larger molecule, known as perchloroethylene or C₂Cl₄, and blasting off its chlorine atoms (Cl) with a high-powered UV laser.”

The newly-made dicarbon molecules were sent travelling through a gas beam in a vacuum chamber, which was around two metres long.

The team then pointed another two UV lasers towards the dicarbon: one to flood it with radiation, the other to make its atoms detectable. The radiation hit ripped the dicarbon apart, sending its carbon atoms flying onto a speed detector.

By analysing the speed of these quickly-moving atoms, the team could measure the strength of the carbon bond to about one in 20,000 — which is like measuring 200 metres to the nearest centimetre.

Ms Borsovszky says due to the complexity of the experiment it took nine months before they were able to make their first observation.

“We were about to give up,” she says. “It took so long to make sure everything was precisely lined up in space and time.

“The three lasers were all invisible, so there was a lot of stabbing in the dark — quite literally.”

Prof. Schmidt says this is the first time anyone has ever observed this chemical reaction.

“It’s extremely satisfying to have solved a conundrum that dates back to the 1930s.”

Solving space mysteries

There are around 3700 known comets in the solar system, although it’s suspected there could be billions more. On average, a comet’s nucleus is a whopping 10 kilometres wide — but its coma is often 1000 times bigger.

Bright comets can put on spectacular shows for those lucky enough to see them. But in the past, comets might have done more than that for Earth — in fact, one of the theories about the origin of life is that comets once delivered the building blocks of life right to our doorstep.

“This exciting research shows us just how complex processes in interstellar space are,” says Professor Martin van Kranendonk, a UNSW astrobiologist and geologist who was not involved in the study.

“Early Earth would have experienced a jumble of different carbon-bearing molecules being delivered to its surface, allowing for even more complex reactions to occur in the leadup to life.”

Now that the case of the missing green tail in comets is solved, Prof. Schmidt, who specialises in space chemistry, wants to continue solving other space mysteries.

Next, he hopes to investigate diffuse interstellar bands: patterns of dark lines between stars that don’t match any atom or molecule we know of.

“Diffuse interstellar bands are a pretty big unsolved mystery,” he says. “We don’t know why the light that’s arriving on Earth often has nibbles taken out.

“This is just one more mystery in a huge inventory of bizarre things in space that we’re yet to discover.”

And yet, a new study supports the longstanding idea that if life exists, it might make a home in Venus’ clouds. The study’s authors, from MIT, Cardiff University, and Cambridge University, have identified a chemical pathway by which life could neutralize Venus’ acidic environment, creating a self-sustaining, habitable pocket in the clouds.

Within Venus’ atmosphere, scientists have long observed puzzling anomalies — chemical signatures that are hard to explain, such as small concentrations of oxygen and nonspherical particles unlike sulfuric acid’s round droplets. Perhaps most puzzling is the presence of ammonia, a gas that was tentatively detected in the 1970s, and that by all accounts should not be produced through any chemical process known on Venus.

In their new study, the researchers modeled a set of chemical processes to show that if ammonia is indeed present, the gas would set off a cascade of chemical reactions that would neutralize surrounding droplets of sulfuric acid and could also explain most of the anomalies observed in Venus’ clouds. As for the source of ammonia itself, the authors propose that the most plausible explanation is of biological origin, rather than a nonbiological source such as lightning or volcanic eruptions.

As they write in their study, the chemistry suggests that “life could be making its own environment on Venus.”

This tantalizing new hypothesis is testable, and the researchers provide a list of chemical signatures for future missions to measure in Venus’ clouds, to either confirm or contradict their idea.

“No life that we know of could survive in the Venus droplets,” says study co-author Sara Seager, the Class of 1941 Professor of Planetary Sciences in MIT’s Department of Earth, Atmospheric and Planetary Sciences (EAPS). “But the point is, maybe some life is there, and is modifying its environment so that it is livable.”

The study’s co-authors include Janusz Petkowski, William Bains, and Paul Rimmer, who are affiliated with MIT, Cardiff University, and Cambridge University.

Life suspect

“Life on Venus” was a trending phrase last year, when scientists including Seager and her co-authors reported the detection of phosphine in the planet’s clouds. On Earth, phosphine is a gas that is produced mainly through biological interactions. The discovery of phosphine on Venus leaves room for the possibility of life. Since then, however, the discovery has been widely contested.

“The phosphine detection ended up becoming incredibly controversial,” Seager says. “But phosphine was like a gateway, and there’s been this resurgence in people studying Venus.”

Inspired to look more closely, Rimmer began combing through data from past missions to Venus. In these data, he identified anomalies, or chemical signatures, in the clouds that had gone unexplained for decades. In addition to the presence of oxygen and nonspherical particles, anomalies included unexpected levels of water vapor and sulfur dioxide.

Rimmer proposed the anomalies might be explained by dust. He argued that minerals, swept up from Venus’ surface and into the clouds, could interact with sulfuric acid to produce some, though not all, of the observed anomalies. He showed the chemistry checked out, but the physical requirements were unfeasible: A massive amount of dust would have to loft into the clouds to produce the observed anomalies.

Seager and her colleagues wondered if the anomalies could be explained by ammonia. In the 1970s, the gas was tentatively detected in the planet’s clouds by the Venera 8 and Pioneer Venus probes. The presence of ammonia, or NH_3, was an unsolved mystery.

“Ammonia shouldn’t be on Venus,” Seager says. “It has hydrogen attached to it, and there’s very little hydrogen around. Any gas that doesn’t belong in the context of its environment is automatically suspicious for being made by life.”

Livable clouds

If the team were to assume that life was the source of ammonia, could this explain the other anomalies in Venus’ clouds? The researchers modeled a series of chemical processes in search of an answer.

They found that if life were producing ammonia in the most efficient way possible, the associated chemical reactions would naturally yield oxygen. Once present in the clouds, ammonia would dissolve in droplets of sulfuric acid, effectively neutralizing the acid to make the droplets relatively habitable. The introduction of ammonia into the droplets would transform their formerly round, liquid shape into more of a nonspherical, salt-like slurry. Once ammonia dissolved in sulfuric acid, the reaction would trigger any surrounding sulfur dioxide to dissolve as well.

The presence of ammonia then could indeed explain most of the major anomalies seen in Venus’ clouds. The researchers also show that sources such as lightning, volcanic eruptions, and even a meteorite strike could not chemically produce the amount of ammonia required to explain the anomalies. Life, however, might.

In fact, the team notes that there are life-forms on Earth — particuarly in our own stomachs — that produce ammonia to neutralize and make livable an otherwise highly acidic environment.

“There are very acidic environments on Earth where life does live, but it’s nothing like the environment on Venus — unless life is neutralizing some of those droplets,” Seager says.

Scientists may have a chance to check for the presence of ammonia, and signs of life, in the next several years with the Venus Life Finder Missions, a set of proposed privately funded missions, of which Seager is principal investigator, that plan to send spacecraft to Venus to measure its clouds for ammonia and other signatures of life.

“Venus has lingering, unexplained atmospheric anomalies that are incredible,” Seager says. “It leaves room for the possibility of life.”

This research was supported in part by the Simons Foundation, the Change Happens Foundation, and the Breakthrough Initiatives.

In a paper published Dec. 17 in the journal Science Advances, authors from The University of Texas Health Science Center at San Antonio (also referred to as UT Health San Antonio) report that norepinephrine, a fundamental chemical for brain performance, is locally regulated in a brain region called the visual cortex.

“Before our study, research suggested the possibility of local regulation of norepinephrine release, but it had never been directly demonstrated,” said study senior author Martin Paukert, MD, assistant professor of cellular and integrative physiology at UT Health San Antonio. The work of the team, which included Shawn R. Gray, PhD, and Liang Ye, MD, from the Paukert lab and Jing Yong Ye, PhD, from the biomedical engineering department at The University of Texas at San Antonio, was supported by the Robert J. Kleberg, Jr. and Helen C. Kleberg Foundation, the National Institute of Mental Health (NIMH) and the National Institute on Alcohol Abuse and Alcoholism (NIAAA).

Norepinephrine is known to be involved in paying attention. “A certain amount of this chemical needs to be released for optimum brain performance and ability to pay attention,” Dr. Paukert said. “So, if there is either too much of it or too little of it, it may affect how we process information.”

Disease states in which norepinephrine is known to be altered include substance use disorders, Alzheimer’s disease, post-traumatic stress disorder (PTSD) and attention-deficit/hyperactivity disorder (ADHD). In some substance use, Alzheimer’s and ADHD, the release of norepinephrine is reduced, resulting in lower attention. In other substance use and PTSD, the level is too high.

The team’s findings also extend to cells called astrocytes that function as helper cells in the brain and central nervous system.

“When a person makes a movement, such as turning the head to listen to a parent, and that is combined with visual stimulation, then more norepinephrine is released where visual information is processed,” Dr. Paukert said. “Our second finding, also important, is that astrocytes can reliably detect the rate of norepinephrine release.”

They are sensitive to it, in other words. Astrocytes alter their response accordingly, which is expected to change brain performance.

“Understanding norepinephrine release, its local regulation and the astrocyte response may represent a mechanism by which one could enhance sensory-specific attention,” Dr. Paukert said. Research will continue in that direction.

In a study published today in the journal Science, researchers at The Ohio State University used a magnetic microscope to visualize the patterns, formed in thin films of an unusual magnetic material, manganese germanide. Unlike familiar magnets such as iron, the magnetism in this material follows helices, similar to the structure of DNA. This leads to a new zoo of magnetic patterns with names such as hedgehogs, anti-hedgehogs, skyrmions and merons that can be much smaller than today’s magnetic bits.

“These new magnetic patterns could be used for next-generation data storage,” said Jay Gupta, senior author of the study and a professor of physics at Ohio State. “The density of storage in hard disks is approaching its limits, related to how small you can make the magnetic bits that allow for that storage. And that’s motivated us to look for new materials, where we might be able to make the magnetic bits much smaller.”

To visualize the magnetic patterns, Gupta and his team used a scanning tunneling microscope in his lab, modified with special tips. This microscope provides pictures of the magnetic patterns with atomic resolution. Their images revealed that in certain parts of the sample, the magnetism at the surface was twisted into a pattern resembling the spikes of a hedgehog. However, in this case the “body” of the hedgehog is only 10 nanometers wide, which is much smaller than today’s magnetic bits (about 50 nanometers), and nearly impossible to visualize. By comparison, a single human hair is about 80,000 nanometers thick.

The research team also found that the hedgehog patterns could be shifted on the surface with electric currents, or inverted with magnetic fields. This foreshadows the reading and writing of magnetic data, potentially using much less energy than currently possible.

“There is enormous potential for these magnetic patterns to allow data storage to be more energy efficient,” Gupta said, though he cautions that there is more research to do before the material could be put into use on a data storage site. “We have a huge amount of fundamental science still to do about understanding these magnetic patterns and improving how we control them. But this is a very exciting step.”

This research was funded by the Defense Advanced Research Projects Agency, a research division of the U.S. Department of Defense. Other Ohio State researchers who co-authored this study include Jacob Repicky, Po-Kuwan Wu, Tao Liu, Joseph Corbett, Tiancong Zhu, Shuyu Cheng, Adam Ahmed, Mohit Randeria and Roland Kawakami.

Story Source:

Materials provided by Ohio State University. Original written by Laura Arenschield. Note: Content may be edited for style and length.

After studying the impacts of mining cobalt — a common ingredient in lithium-ion batteries — on communities in Africa’s Democratic Republic of the Congo (DRC), an interdisciplinary team of researchers led by Northwestern University is calling for more data into how emerging technologies affect human health and livelihoods.

Such data can inform policymakers, industry leaders and consumers to make more socially and ethically responsible decisions when developing, funding and using green technologies.

The case study and perspective paper will be published on Dec. 17 in the journal One Earth.

“We have the framework and tools available to compare the environmental costs of automobiles that run on fossil fuels to battery-powered vehicles,” said Northwestern’s Jennifer Dunn, who led the study. “I can tell you the greenhouse gas emissions per mile for either one. But when it comes to the social effects, we don’t have the same capability for direct comparison. For many engineers, it’s easier to measure or calculate environmental effects than to understand the social conditions in a faraway country that they have never set foot in.”

Dunn is an associate professor of chemical and biological engineering at Northwestern’s McCormick School of Engineering and associate director of the Center for Engineering Sustainability and Resilience. To conduct the case study, Dunn led an interdisciplinary team of engineers, anthropologists and public health experts.

Environmental vs. human costs

For years, researchers have been conducting environmental life cycle assessments (E-LCA), in which they comprehensively and systematically calculate the environmental impacts of a product all the way from the extraction of raw materials required to make it to its use and ultimate disposal. More recently, researchers have attempted to develop similar frameworks to evaluate social life cycle assessments (S-LCA), which can be used to understand how emerging technologies affect human health and well-being.

To identify barriers to and opportunities for collecting better data for S-LCA, the researchers conducted exploratory field work in cobalt mining communities in the Lualaba Province, DRC. The team collected qualitative data through in-depth interviews and focus-group discussions with miners and other community members. Paper co-author Gabriel Bamana, an anthropologist on faculty at Normandale Community College in Minnesota, is native Congolese and therefore could provide significant cultural and historical context for the study.

“For this type of work, it’s important to work across fields in order to be informed,” said Sera Young, study co-author and associate professor of anthropology at Northwestern’s Weinberg College of Arts and Sciences. “It might be difficult for engineers who are developing the technologies to understand the social effects. By working together, we can form a whole picture of the consequences of resource extraction.”

Unintended consequences of decarbonization

What Dunn and Young discovered was deeply troubling. They found cobalt mining was associated with increases in violence, substance abuse, food and water insecurity, and physical and mental health challenges. Community members reported losing communal land, farmland and homes, which miners literally dug up in order to extract cobalt. Without farmland, Congolese people were sometimes forced to cross international borders into Zambia just to purchase food.

“You might think of mining as just digging something up,” Young said. “But they are not digging on vacant land. Homelands are dug up. People are literally digging holes in their living room floors. The repercussions of mining can touch almost every aspect of life.”

Waste generated from mining cobalt and other metals can pollute water, air and soil, leading to decreased crop yields, contaminated food and water, and respiratory and reproductive health issues. Miners reported that working conditions were unsafe, unfair and stressful. Several workers noted that they feared mineshaft collapses.

As industry leaders move toward decarbonization to slow, stop or even reverse human-caused climate change, technologies are increasingly relying on batteries instead of fossil fuels. Unfortunately, the effects of these technologies on social well-being are understudied and data related to these effects are insufficient for use in policy-making decisions.

“If we’re trying to be do-gooders by caring for the environment, then the environment shouldn’t be limited to only the natural environment — but also the human environment,” said Young, who studies water insecurityacross a range of global contexts.

Offering new solutions

Throughout their work, Dunn, Young and their team found little in the way of established guidance on best practices for conducting S-LCA, including little guidance on how to conduct interviews and a lack of consensus on how to use and analyze data from stakeholders.

“Most of this work has been conceptualized by natural scientists who have limited knowledge about social impacts,” Dunn said. “Measuring environmental effects of a technology is sometimes as simple as adding a sensor to measure emissions. But trying to measure intangible social effects like mental health is much harder.”

“And things that aren’t measured remain invisible,” Young added.

Because the quality of the social impact assessment relies on the quality of the data, the researchers identified five categories of data sources, which can be leveraged to better understand localized effects of mining:

(1) interviews and focus groups of affected community members;

(2) local public records, including land-related court claims, documentation of forced migration and publicly available health records;

(3) cross-culturally validated scales, including data collected by national statistics agencies and organizations such as UNICEF and the World Bank;

(4) data collected for the Sustainable Development Goals; and

(5) remote sensing and imagery, including satellite imagery showing how farmland has changed after cobalt mining is established.

The researchers believe such methods can be applied to other scenarios beyond cobalt mining to gather social data surrounding emerging technologies.

“We have a long way to go before we can put S-LCA results in front of decision-makers in the same way we can with E-LCA results,” Dunn said. “In the meantime, our society is going through huge changes, including climate change, so we feel a sense of urgency. We hope that policy makers recognize the urgency of the human costs of cobalt mining sooner rather than later.”

The study, “Addressing the social life cycle inventory analysis data gap: Insights from a case study of cobalt mining in the Democratic Republic of the Congo,” was supported by Leslie and Mac McQuown, the Northwestern Institute on Complex Systems and the Carnegie Corporation.