It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Monday, October 23, 2023
Neanderthals Might Not Be The Separate Species We Always Thought
Stoop-backed, heavy-browed, communicating in ape-like grunts, impressions of the Neanderthal as a simple-minded brute a few steps below modern humans on the evolutionary ladder have endured since their discovery in the mid-19th century.
That categorization is due for a change, according to a team of researchers who have spent the past twenty years digging through layers of dust and grit in the central Portuguese cave site of Gruta da Oliveira.
"More than different species, I would speak of different human forms," says University of Trento archaeologist Diego Angelucci, the lead author of a recent study summarizing decades of research on what was home to families of Neanderthal more than 71,000 years ago.
Angelucci and his team detailed the occupation of Gruta da Oliveira, which saw Neanderthals intermittently share time in the cave with wolves, lions, brown bears and lynxes between 93,000 and 71,000 years ago.
Among the scattering of stone tools and animal remains were bones that had been burned in a way that provided strong evidence of controlled use of fire.
Cooking a range of meats, including goat, deer, and horses on a hearth that rarely moved out of position, it was clear fire was a central part of everyday Neanderthal life at Gruta da Oliveira.
It's no secret that branches of the hominin family tree have appreciated a good blaze for at least 250,000 years or so. For a significant proportion of that time, those flames were deliberately lit, well managed, and contained with the purpose of cooking, if not also staying warm and keeping predators at bay.
Yet Neanderthals had already long diverged from our shared ancestral lineage by the time anatomically modern humans became recognizably distinct, with some speculating they went their own way more than 800,000 years ago.
The initial discovery of their remains in a quarry back in 1864 represented the dawn of a new era in science – the first inkling that there were once other kinds of human.
Based on distinct differences in anatomy, the Anglo-Irish geologist William King proposed they belonged to their own species, one that stood upright like us only with a hunched, more robust appearance. This long-dead, cave-dwelling relative was assumed to be an intellectual dunce compared with modern humans when viewed through the lens of Victorian-era anthropology.
Evidence that they carefully used fire in their technology only further builds a case that Neanderthal culture was far from simple, and far more akin to our own.
"There is a general agreement among archaeologists that they knew how to use fire," says Angelucci.
"However, one thing is to use fire started by natural processes, such as lightning, another is to make it, feed it with wood and use it for cooking, heating and defense."
Just how they might have started fires isn't yet clear, though Angelucci speculates it might not have been all that different to other Neolithic practices, such as the flint and tinder method used by Ötzi, the Iceman.
With genetic analysis confirming Neanderthals frequently interbred with our own ancestors multiple times through history, the case for them being a separate species weakens only further.
It's unlikely we'll finally see the classification of Homo neanderthalensis fade into obscurity any time soon. Messy, confusing, and as conservative as it is, taxonomy continues to be useful and fundamental to our historical understanding of biology.
Still, as more sibling than cousin, it seems the poor old Neanderthal deserves to sit right by our side in the Homo sapien family portrait.
Astranis is developing microGEO satellites in partnership with Mexico’s APCO Networks. Credit: Astranis
WASHINGTON — The U.S. Space Force is exploring the use of small geosynchronous satellites to enhance military communications networks — either through purchased commercial services or government-owned constellations.
“We’re trying to leverage new capabilities from the commercial industry,” Clare Hopper, chief of the Space Force’s Commercial Satellite Communications Office, said Oct. 19 at the annual MilSat Symposium in Mountain View, California.
Hopper said the Space Force is interested in procuring maneuverable small satellites that can deliver connectivity from geosynchronous Earth orbit.
Her office on Oct. 18 issued a request for information on the capabilities of the microGEO satellite sector, which uses smaller, cheaper satellites that are being marketed as nimbler options than large geosynchronous spacecraft.
The Space Force is “seeking sources capable of supporting a Department of Defense effort launching and maintaining communications satellites that allow for greater maneuverability and smaller size than traditional geostationary satellites,” said the request.
Through this market research, the Space Force wants to assess the advantages and potential risks of using smaller geosynchronous platforms. Companies entering the microGEO sector of the satellite industry include large satcom operators like Intelsat and Inmarsat, and satellite internet startups like Astranis.
Hopper said the plan is to use IDIQ (Indefinite Delivery/Indefinite Quantity) contracts that provide a framework for the Space Force to place task orders for satcom hardware or services on an as-needed basis.
The IDIQ contract, Hopper said, would allow for the procurement of communications services or could give the government the ability to “effectively acquire our own constellation through a unique leasing arrangement.”
Geostationary orbit, 22,236-miles above Earth, has traditionally been the preferred location of communications satellites so antennas on the ground do not have to rotate to track them, and are pointed permanently at the position of the satellite.
But microGEO satellites have not typically been deployed in geo orbits. These satellites are a small fraction of the mass of traditional geocomm satellites, and are being offered as a more flexible alternative.
The Space Force sees small GEO satellites as a means to increase the resiliency of military communications, the RFI said.
It is seeking small satellites “capable of maneuvering between International Telecommunication Union (ITU) assigned orbital slots in the GEO arc,” said the request. “Increased maneuverability utilizing decentralized and spatially dispersed small satellites is imperative for the future resilience of both the constellation and the communications support for users without impact to existing user equipment and gateways.”
Direct-to-cell communications
Hopper said the Space Force also plans to issue a request for information on so-called direct-to-device satellite services.
This is an emerging segment of the satcom industry seeking to provide connectivity to cellphone users via satellites.
Companies like AST SpaceMobile and Lynk Global are developing satellite constellations to provide direct-to-cell services. SpaceX has announced plans for a Starlink direct-to-device cell phone service, promising global coverage from “cell phone towers in space.”
CRUISE ROBOTAXIS UNDER FEDERAL INVESTIGATION FOR ENDANGERING PEDESTRIANS
UH OH.
Stay Clear
The National Highway Traffic Safety Administration has opened an investigation into GM's autonomous vehicle division Cruise, after receiving reports of its robotaxis crashing or almost crashing into pedestrians.
According to a document released by the agency's Office of Defects Investigation this week, the reports involve Cruise robotaxis "encroaching on pedestrians present or entering roadways," including crosswalks near the intended travel path of the vehicles. This raises the risk of a Cruise robotaxi hitting a pedestrian, the NHTSA said, which could cause severe injury or death.
So far, the agency has received two reports involving pedestrian injuries and Cruise robotaxis, and has obtained videos of another two relevant incidents posted to social media. Fortunately, no fatal incidents have been reported, though there has been at least one close call. All told, it's the latest sign of friction between the narrative of safe self-driving cars and the messy reality when they hit public roads — though for its part, Cruise is downplaying the drama.
"Cruise's safety record over 5 million miles continues to outperform comparable human drivers at a time when pedestrian injuries and deaths are at an all-time high," a Cruise spokesperson said in a statement, as quoted by Fortune. Street Savvy
One of the incidents under investigation, which occurred earlier this month, is especially brutal. A pedestrian in San Francisco was struck by a human driver in a hit and run, knocking her into the path of a Cruise robotaxi which appeared to then run her over. GM claims that its self-driving vehicle slammed its brakes to "minimize the impact."
The details of that collision remain hazy, and as Cruise argues, it may have been impossible for the robotaxi to stop or swerve in time. Still, even when they aren't endangering pedestrians, it’s clear that the self-driving vehicles are causing their fair share of chaos on the streets they roam.
Regular drivers haven't been loving sharing the streets with them, either. The robotaxis vehicles have causedtraffic jams, and whole groups of them have, on more than one occasion, suddenly shut down in the middle of the road.
With all that bad PR in mind, an NHTSA investigation could be yet another costly setback for GM, which has lost billions of dollars on Cruise since 2018. We'll have to see how it will weather this latest storm.
This image shows a long filament of solar material, erupting into space. It happened on August 31, 2012. The accompanying coronal mass ejection (CME) traveled at over 900 miles per second (1,500 km/sec), rippling out into the solar system. Note: Earth to scale, but Earth is not this close to the sun. Image via NASA/ SDO spacecraft. A much-larger CME in the year 1859 caused the Carrington Event, which manifested as perplexing disruptions in the technologies then in use, such as the telegraph. In our world – with our much-greater dependence on technology – what would happen if a Carrington Event occurred again?
The sun – our blazing star – has a metaphorical dark side. It has the potential to cause our modern technological civilization to falter. We had a taste of our sun’s destructive effects on September 2, 1859. On that day, around the world, compasses at sea failed to work, causing some ships to become lost. Telegraph networks experienced disruption, with some telegraph lines catching fire. Tellingly, people as far south as the Caribbean and Mexico saw auroras. Scientists now believe that what happened on that day – 164 years ago – was an extreme geomagnetic storm. Since then, the 1859 storm has become known as the Carrington Event.
Many scientists and others wonder … what would happen if a Carrington Event took place today?
Richard Carrington was a well-known British astronomer of the 19th century. His focus was the sun. He determined the position of the sun’s axis of rotation (the location of its north and south poles) and was the first to learn that the sun doesn’t rotate as a solid body, but that solar material goes around faster at the sun’s equator than at its poles. He discovered that the dark spots on the sun’s surface, called sunspots, vary in latitude over the 11-year solar cycle. He and Richard Hodgson saw the first bonafide solar flare.
On the first day of September 1859, he was observing sunspots when he saw a bright flash of light. Scholars now believe he saw the mighty corona mass ejection (CME) – the powerful eruption near the sun’s surface, driven by kinks in the solar magnetic field – whose resulting shocks rippled through our solar system. One day later, on Earth, a great storm occurred in our world’s magnetic field. The effects of that great geomagnetic storm are now called the Carrington Event.
Coronal mass ejections (CMEs)
CMEs are common on the sun, especially when the sun is near the peak of its 11-year solar cycle. And aurora-watchers welcome them, because they cause the beautiful displays of auroras, aka northern or southern lights, seen at high latitudes. Nowadays, our spacecraft routinely record CMEs. But, in the 19th century, CMEs hadn’t been discovered yet (although there’d been hints that they existed).
Not until 1971 did the Helios spacecraft discover CMEs from ultraviolet observations.
Carrington Event report
Carrington immediately reported the flash to the Royal Astronomical Society. He probably didn’t give it much more thought until the next day … when the fast-moving solar particles had had time to travel across space to Earth, causing the geomagnetic field to go haywire. Wrapping Earth in a seething, writhing mass of high-energy particles, the blast of solar particles buffeted, squeezed and distorted Earth’s magnetosphere, releasing an estimated 1026 electron volts of energy. That’s a ten followed by 26 zeroes. This amount of energy is equal to a 10-megaton nuclear bomb. It’s also equal to the amount of energy the sun releases in about 10 seconds.
It was the most powerful solar event ever yet recorded.
The effects of the Carrington Event
The effects of the September 2, 1859, solar storm were unprecedented. People saw auroras as far south as the Caribbean and Mexico. At some more northerly latitudes, it’s said the sky was so bright with auroras that birds, thinking it was morning, began to sing. But it wasn’t all awe and beauty. There were widespread stories of people receiving shocks from doorknobs and other metal objects, thanks to the induction of electrical currents. Around the world, compasses at sea failed to work, causing some ships to become lost. Telegraph networks experienced disruption, with some telegraph lines catching fire.
One apocryphal tale tells of a telegraph operator who received a shock from his machine, knocking him unconscious and awaking later to find his arm paralyzed. This story, while remaining uncorroborated, is certainly not beyond the realm of possibility.
The extreme geomagnetic storm subsided the following day. Work began to repair telegraph networks. The brilliant auroras faded from view, and the world returned to normal.
But the stories of the event remain to this day.
A bit of background
The Carrington Event was an extreme geomagnetic storm. To understand the 1859 event, we must understand the solar cycle. German amateur astronomer Samuel Heinrich Schwabe had just discovered the 11-year cycle in the year 1843. Schwabe had been observing the sun for over 17 years when he noticed that the number of sunspots on the sun’s surface varied over time. He also noticed that the period of this variation was about 11 years.
Schwabe’s discovery was a breakthrough in our understanding of the sun. It showed that our star is not a static object, but rather dynamic and ever-changing.
And – thanks to Schwabe’s tracking of the solar cycles – we know that the peak of Solar Cycle 10 was in February 1860. The Carrington Event happened just months earlier, in September 1859.
The sun’s magnetic field
The sun’s magnetic field creates the 11-year solar cycle, which peaks when the north and south magnetic poles of the sun swap places. Around the peak of each cycle, for a few years on either side, the sun can experience violent events, including increased coronal mass ejections (CMEs). We’re in such a time now, by the way. The peak of the current solar cycle is expected in the mid-2020s. You can read the sun news each day at EarthSky’s daily sun post.
When a CME leaves the sun, the sun expels around a billion tons of matter. And sometimes this solar material is directed toward Earth. When it arrives, the Earth experiences a geomagnetic storm, usually not an extreme one, but an awesome event nonetheless. At such times, the solar wind slams into our planet’s magnetic field, infusing Earth’s magnetosphere with high-energy particles.
From our viewpoint on the surface of Earth, one immediate effect is beautiful, bright auroras as the particles collide with atoms in the upper atmosphere, imparting their energy and causing the atoms to glow. This is a geomagnetic storm, and it can last for many hours.
Artist’s concept of activity on the sun traveling across space to interact with Earth’s magnetic field. Not to scale. The sun’s activity can cause a geomagnetic storm, which can harm earthly technologies. Image via NASA/ Wikimedia Commons (public domain).
News reports from the time
The Carrington Event was a hot story in newspapers of the day. The September 2, 1859, edition of The New York Times reported:
Last night the city was visited by one of the most brilliant displays of the aurora borealis that has been witnessed for many years. The sky was clear, and the stars shone with unusual brilliancy. About nine o’clock a faint light appeared in the north, which gradually increased in brightness until it reached the zenith. The aurora then assumed a variety of forms, and the sky was constantly changing. At times the whole heavens were illuminated with a brilliant light, and the stars were entirely obscured. The aurora continued for several hours and disappeared about midnight.
On September 3, 1859, The Boston Globe reported:
Yesterday there was a great magnetic storm which affected all the telegraph lines in the country. The telegraph lines in Boston were all interrupted for several hours, and some of them were so badly injured that they will not be repaired for several days. The storm also affected the magnetic compasses on ships, and some vessels lost their way.
And on September 5, 1859, The London Times reported:
On the night of the 1st and 2nd of September … the magnetic compasses were so much affected that it was impossible to steer by them. The aurora borealis was seen in many places where it is rarely seen, and in some places it was so bright that it was possible to read by it.
If a Carrington Event happened today
Today we live in a completely different world. Our technology is advanced, complex and ubiquitous. Where once telegraph lines sang their messages across the flat midwestern plains of the United States, now it’s the internet that connects us and everything we do.
The first undersea transatlantic telegraph cable came just a year before the Carrington Event, in 1858. It connected North America with Europe for the first time, allowing news to propagate around the world faster than ever before. Today, most of the world’s internet traffic flows through undersea cables of vast capacity. Existing cables flow with ever-multiplying streams of ones and zeroes, the telegraph songs of the digital age.
Computers manage our society. They affect every single aspect of our lives, from traffic control to power grids to banking to healthcare to entertainment. The birth of the integrated circuit gave us the modern world, appearing in all modern devices from toasters to televisions and cellphones to cars. What might another Carrington-type event do, if it were to induce large electrical currents in Earth’s magnetic field? What might happen to national power grids?
There would almost certainly be widespread burnout of electronic circuits and the failure of power grids on a much bigger scale than the 1989 Quebec blackout from a solar storm. Many, many millions of people would likely be without power and unable to use phones or other devices.
The effects on satellites
In space, satellites would also fail as their electronics fried. This has happened several times during geomagnetic storms on a scale far smaller than the Carrington Event. The most recent was in March 2022, when 40 SpaceX Starlink satellites failed after a CME. They launched the day before the storm hit. But it wasn’t their electronic systems that failed. One effect of a geomagnetic storm is to increase atmospheric drag on the satellites. It pulled the satellites back toward Earth, where they burned up in the atmosphere.
Only about 1% of the world’s internet traffic transmits via satellite. However, in the banking industry, ATM and credit card transactions, the transfer of funds and banking messages all travel through satellites. Widespread communication loss would be inevitable. There would be utter chaos for a while. Recovery might take years.
Predicting the next one
If all this sounds frightening to you, let’s ask an important question to put it all in perspective. Just how likely is another Carrington Event? After all, it’s been 164 years since the last one. So do we view it as a blip, or do such events recur on longer timescales, or perhaps even at regular intervals? Can we predict the next storm and what its effects might be? And – perhaps the most important question – just how much notice might we get of an extreme, Carrington-like event?
Let’s start with the source of the problem: coronal mass ejections or CMEs. Yes, we know much more than we did about them since their discovery in 1971. But CMEs are unpredictable. Apart from the fact that they occur more frequently around solar maximum, due to that reorientation of the sun’s magnetic field, we don’t yet know enough about the mechanisms that generate CMEs to say when they will occur.
So, we have no way of knowing when a event similar to the Carrington Event might occur again. We also don’t know how often these events occurred before 1859. Before there were electric grids or devices, such storms probably went unrecorded apart from mentions of brilliant auroras.
Preparing for the next one
How much notice might we receive of an impending, society-changing, potentially catastrophic storm? Well, you’ll be pleased to know that scientists are fully aware of the dangers. They’re working hard using artificial intelligence to model when and where they could hit worst. NASA heliophysicists have created a system called DAGGER, but it could only give us an estimated 30 minutes’ warning of an approaching storm.
We now have the sun under constant observation from Earth and satellites. But when the sun releases a CME, it’s difficult to work out exactly how much material will hit us. Put simply, we don’t know which ones are the dangerous ones.
Hope rests on attaining a greater, more holistic and in-depth understanding of the sun’s magnetic field. One day, we might be able to predict the destructive geomagnetic storms of the future. We can harden our technology and power grids against damage in the same way that spacecraft have their electronics hardened against electrical currents. But that requires lots of money and the world’s politicians to recognize the dangers and act.
So far, they have not allocated nearly enough money and resources to protect us from civilization-destroying asteroids or, of course, the effects of climate change. There’s little reason to be optimistic that those in power will take the threat of another Carrington Event seriously.
Learning lessons from the Carrington Event
The Carrington Event, in the end, caused minimal damage in an age when there was little which could be damaged. But were it to occur today, it would be catastrophic. We really need to learn the lessons from our ancestors and treat the sun seriously as a threat as well a life-giver. If we do not, we will only have ourselves to blame when the next extreme geomagnetic storm hits.
Bottom line: The Carrington Event of 1859 was a massive geomagnetic storm triggered by activity on the sun. People saw auroras at low latitudes that were bright enough to read by.
About the Author: Andy Briggs has spent the past 30 years communicating astronomy, astrophysics and information technology to people. You can hear his weekly astronomy and space news update, on Mondays, on the global internet radio channel AstroRadio (http://www.astroradio.earth), where he also contributes to other programmes. He has been active in many astronomy societies in the UK and is a frequent contributor to Astronomy Ireland magazine. Andy also lectures regularly on astrophysics-related themes such as gravitational waves and black holes. He lives in Catalonia, Spain, with his daughter.
Artificial coral reefs showing early signs they can mimic real reefs killed by climate change, says study
Earth's average temperature in September 2023 was 1.75°C above its pre-industrial baseline, breaching (if only temporarily) the 1.5°C threshold at which world leaders agreed to try and limit long-term warming.
Persistent warming at this level will make it difficult for the ocean's coral reefs to survive. The same goes for those communities who rely on the reefs for food, to protect their coastline from storms and for other sources of income, such as tourism. Recent Intergovernmental Panel on Climate Change assessments have predicted that even if global heating is kept within the most optimistic scenarios, up to two-thirds of all coral reefs could deteriorate over the next few decades.
It will not be possible to restore all the reefs lost to climate change. But we are scientists who study how to preserve these habitats, and we hope that artificial structures (made from concrete or other hard materials) could replicate the complex forms of natural reefs and retain some of the benefits they provide.
We know artificial reefs can attract fish and host high levels of biodiversity—often similar to natural reefs. This is partly due to them providing a hard surface for invertebrates like sponges and corals to grow on. Artificial reefs also offer a complex habitat of crevices, tunnels and other hiding places for species that move around a lot, such as fish, crabs and octopus.
Until now though, scientists were unsure if artificial reefs attracted wildlife which would otherwise live on nearby coral reefs or whether they helped support entirely new communities, enlarging existing populations. This is important, because if natural reefs do die, these artificial structures must be self-sustaining to continue benefiting species, including our own.
Our recent study published in Marine Biology is the first to examine whether artificial reefs in the tropics can function in the same way as their naturally formed counterparts. The answer is: not yet, but these concrete structures are beginning to mimic some of the key functions of coral reefs—and they should get better at it over time.
Follow the nutrients
Coral reefs support lots of different species in high numbers despite growing in tropical waters low in nutrients (chemicals such as nitrates and phosphates which boost plant growth). This puzzled naturalist Charles Darwin, and it became known as Darwin's Paradox. We now know reefs achieve this by circulating nutrients extremely rapidly through the invertebrates, corals and fish that live on them.
In a healthy coral reef system, nutrients from dead animals and feces are rapidly consumed by animals living on the reef, such as small fish or invertebrates, and these small animals are frequently eaten by larger animals. This ensures these nutrients cannot accumulate and so they remain at low levels, preventing algae from overgrowing and smothering the reef.
If artificial reefs perform a similar function to natural reefs then we would expect them to rapidly process nutrients entering the system and keep overall nutrient levels low too. This would indicate they are also highly productive ecosystems, similarly capable of supporting diverse and abundant wildlife even if many natural reefs die.
We tried to make an accurate comparison of natural and artificial reefs by comparing nutrient levels and how they are stored between the two.
From concrete to corals
Our study was conducted in north Bali, Indonesia. A local non-profit, North Bali Reef Conservation, which Zach co-founded, has been making artificial reefs for the last six years with the help of international volunteers and local fishers who use their boats to drop them offshore.
While over 15,000 reefs have been deployed so far, they only cover around 2 hectares—roughly the size of two football pitches.
But these structures are beginning to show signs of functioning like coral reef communities. In water we extracted from just under the sand near the artificial reefs we found high levels of phosphates—evidence of a large number of fish excreting. And in water samples from above the sediment, levels of all the nutrients we measured were low and similar to those recorded on natural reefs, indicating the artificial reef was rapidly recycling these nutrients.
However, the sediment around the concrete structures we tested appeared to be storing less carbon than that surrounding the natural reefs. We think the difference may be related to the relative abundance of invertebrate species such as hydroids (plant-like relatives of corals which feed by sifting detritus from seawater). These were common on the natural reefs we studied, but were only found in small, but increasing numbers on the artificial reefs. We think, as more of these species colonize the concrete over time, the reefs will function even more like their natural counterparts.
The study offers some hope that over time, artificial reefs can mimic more of the processes maintained by natural reefs. Our findings are an early indication that artificial reefs may be able to support local communities affected by reefs lost to climate change.
The climate threat to coral reefs will not be solved by artificial reefs. Only rapidly eliminating emissions of greenhouse gases can preserve a future for these ecosystems. But our research indicates that, where reefs have already been lost, through pollution, destructive fishing or coastal development, it may be possible to restore some of the lost benefits with artificial structures.
Our study suggests it can take up to five years for artificial reefs to begin functioning like coral reefs, so these recovery programs must begin right away.
More information: Zach Boakes et al, Nutrient dynamics, carbon storage and community composition on artificial and natural reefs in Bali, Indonesia, Marine Biology (2023). DOI: 10.1007/s00227-023-04283-4
Further evidence of Earth's core leaking found on Baffin Island
by Bob Yirka , Phys.org
Schematic illustration of core-to-plume transfer. Credit: Nature (2023). DOI: 10.1038/s41586-023-06590-8
A combined team of geochemists from Woods Hole Oceanographic Institution and California Institute of Technology has found evidence of high levels of helium-3 in rocks on Baffin Island—possible evidence that the Earth's core is leaking. In their paper published in the journal Nature, the group describes their study of helium-3 and helium-4 on the Canadian Arctic Archipelago.
Prior researchers found trace elements of helium-3 in lava flows on Baffin Island, hinting at the possibility that the Earth's core might be leaking. This is because it is an ancient isotope—it was prevalent during the time when Earth was forming and became trapped in the core. But because of its nature, helium-3 that makes its way to the surface soon escapes into the atmosphere and disappears into space. Thus, helium-3 is rare. If it is found on the surface, the odds are high that it made its way out of the core.
Intrigued by the possibility that the Earth's core might be leaking, the research team ventured to Baffin Island and began testing multiple lava flows. They found much higher levels of helium-3 than observed in prior research efforts—higher than anywhere else on Earth. They also found high ratios of helium-3 to helium-4 (a common isotope)—the highest that have ever been measured in terrestrial rock. Such high ratios, the researchers suggest, is another factor suggesting that the helium-3 is leaking from the core.
The research team notes that finding such high levels of helium-3 at a terrestrial site is a big deal, because if it can be proved that the material is indeed leaking from the core, it will provide scientists with a way to study core material, which has never been done before. That could reveal more about the core than previously thought possible. They note that if the helium-3 is coming from the core, then the other material around it should be as well, offering further physical examples of core material.
More information: F. Horton et al, Highest terrestrial 3He/4He credibly from the core, Nature (2023). DOI: 10.1038/s41586-023-06590-8
