Amazon announced its first LEO maritime broadband reseller agreements Feb. 10, as it prepares to deploy another batch of satellites this week on the inaugural flight of Europe’s Ariane 64 rocket.
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MOUNTAIN VIEW, Calif. – The Aerospace Corp. is sharing DiskSat technology with industry partners as the first four pancake-shaped spacecraft undergo commissioning. Orbotic Systems, a Southern California startup focused on space debris remediation, and San Francisco-based edge computing startup Satylt have signed the first DiskSat commercial licensing agreements. “This is an opportunity for commercial, international, […]
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Non-venture investment in space startups surged last year to its highest level since a 2021 spike driven by a wave of special purpose acquisition company mergers, according to BryceTech analysis.
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SAN FRANCISCO – Spaceium, a startup planning to establish a network of in-space refueling and repair stations, demonstrated the actuator for its robotic arm in space. Extensive testing of Spaceium’s actuator, which flew on Transporter-15, the SpaceX Falcon 9 rideshare launched in November, confirmed its accuracy.“We tested the actuator first, because our technology revolves […]
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A satellite to be built by Canadian startup Galaxia for launch in 2027 is being lined up for a study aimed at improving California-based Apolink’s proposed in-orbit data relay services.
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Entanglement is a key resource for quantum computation and quantum technologies, but it can also tell us much about a computational problem. That is the conclusion of a recent paper by Achim Kempf and Einar Gabbassov – who are applied mathematicians at Canada’s University of Waterloo and are affiliated with Waterloo’s Institute for Quantum Computing and the Perimeter Institute for Theoretical Physics. Writing in Quantum Science and Technology, Gabbassov and Kempf show how entanglement plays a fundamental role in determining both the efficiency and the hardness of quantum computation problems.
They considered the role of entanglement in adiabatic quantum computing. This considers a landscape of hills and valleys (the problem) where the shape of the landscape depends on the problem to be solved. A point on the landscape represents a candidate solution to the problem. This could be a configuration of possible states of three qubits, for example, or “a possible schedule for truck routes, or a particular shape for a pharmaceutical molecule” says Kempf. The actual solution to the problem is then the lowest (deepest) point in the landscape, which corresponds to the lowest energy point (the minimum point or minima).
This minima is easy to find if the landscape is smooth and has only one valley. The problem is harder if there are multiple valleys (a rugged landscape) since you might get stuck in a valley you believe to be the deepest, but which is not, and then you would have to climb out of it.
In a classical computation, every possible valley must be checked one-by-one to find the deepest one. However, Kempf explains that “in adiabatic quantum computing, the computer keeps track of all the valleys at once, by connecting them internally using entanglement”. Classically, many possibilities just means many independent guesses of the deepest valley. With quantum effects, when one part of the landscape shifts, it affects the whole landscape all at once. He explains that instead of checking each valley one-by-one, we can check them all simultaneously, significantly increasing the speed at which the lowest point in the landscape is found.
When given a difficult problem with many valleys, there is a risk of getting stuck in a valley that is shallow and not being able to climb out and find the lowest energy state. Adiabatic quantum computing gets around this issue through a clever shapeshifting of the landscape.
The process starts with an easy landscape, comprising only one valley. Since the solution is simple, the the deepest valley corresponding to the lowest energy state is occupied quickly. Gradually the landscape is changed to contain more and more valleys, more closely approximating the more complicated landscape whose lowest point is the solution.
The lowest point changes with each change in the landscape, but the trick is that if the changes in the landscape are small enough, the deepest part of the landscape and therefore the lowest energy state will always be occupied. This is the basic principle of adiabatic quantum computing often used in resource allocation, routing and logistics, and machine learning where there can be huge numbers of possible variable configurations.
In their work, Gabbassov and Kempf explore how the amount of entanglement required to find the deepest valley links to the difficulty and time needed to complete the problem.
A difficult problem would be a rugged landscape consisting of multiple valleys of similar depth located far apart from one another. To occupy the lowest energy state, we need to occupy all these valleys simultaneously. The entanglement needed to do this is greater since the interconnectedness between the valleys is harder to maintain when they are further apart (they have a large Hamming distance). The problem is also harder to solve since it is more difficult to discern which of these valleys is the deepest when they have a similar depth – being close in energy. This added difficulty is reflected in a need for a greater amount of entanglement to keep track of the valleys but also in a greater amount of time needed to distinguish the depths of the valleys to find the deepest one.
Gabbassov and Kempf show that a large amount of entanglement is needed at these difficult, bottleneck points of the computation. This makes it even more difficult to keep track of the valleys and more time is required to avoid falling into the wrong one. This is also where classical computation would normally slow down. Quantum effects are therefore most valuable and are most crucial at these points, proving essential for identifying when and where adiabatic quantum computation can provide a genuine advantage over classical methods.
Kempf summarizes this as, “the hardness of any computational problem, directly translates into the corresponding widespreadness of entanglement the quantum computer needs to keep track of all the valleys so that it can find the minimum point. Calculational hardness therefore means the need for sophisticated entanglement. Since entanglement is a precious and fragile resource, a hard problem that requires a lot of it can only be solved slowly.”
Entanglement therefore proves to be a useful tool not just for significantly increasing the computational speed of problems but also in characterizing problem difficulty and computation speed. As Gabbassov notes “if we want to devise faster quantum algorithms, we should look not just at the amount of entanglement but also at how this entanglement redistributes/flows” and therefore the structure of the problem. Their work shows that the amount of entanglement used as a resource is more subtle than just providing a general computational speed-up.
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As NASA prepares to launch a new crew to the International Space Station, the agency has yet to decide which spacecraft it will use for the next crew-rotation mission.
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A few years ago, Swiss seismologist Verena Simon noticed a striking shift in the pattern of seismic activity and micro earthquakes in the Mont Blanc region. She found that microquakes in the area, which straddles Switzerland, France and Italy, have fallen into an annual pattern since 2015.
Simon and colleagues at the Swiss Seismological Service in fact found that this annual pattern is linked to heat waves driven by climate change. But they are not the only researchers finding such geophysical links to climate change. There is growing evidence that global warming could cause changes in seismicity, volcanic activity and other such hazards.
In the first eight years from 2006, Simon’s team saw no clear pattern. But then from 2015 they found that seismicity always increases in autumn and stays at a higher level until winter. The researchers wondered if the seasonal pattern was linked to a known increase in meltwater infiltration into the Mont Blanc massif in late summer and autumn every year.
Scientists have long known that when water percolates underground it increases the pressure in gaps, or pores, in rocks, which alters the balance of forces on faults, leading to slips – and triggering seismic activity.
In the late 1990s researchers analysed water flow into the 12 km long Mont Blanc tunnel, which links France and Italy (La Houille Blanche 86 78). They also found a yearly pattern, with a rapid increase in water entering the tunnel between August and October. The low mineral content of the water and results from tracer tests, using fluorescent dyes injected into a glacier crevasse on the massif, confirmed that this increased flow was fresh water from snow and glacier melt.
To explore the seasonal trend in the water table, Simon and colleagues created a hydrological model (a simplified mathematical model of a real-world water flow system) using the tunnel inflow data; plus metrological, hydrological and snow-pack data from elsewhere in the Alps. They also included information on how water diffuses into rocks, alters pore pressure and increases seismic activity (Earth and Planetary Sci. Lett. 666 119372).
When combined with their seismicity data, autumn seismic activity appeared to be triggered by spring surface runoff, which arises from melting glacial ice and snow. The exact timing depends on the depth of the microquakes, with shallow quakes being linked to surface runoff from the previous year, while there is a two-year delay between runoff and deeper quakes. Essentially, their work found a link between meltwater and seismic activity in the Mont Blanc massif; but it could not explain why the autumn increase in microquakes only started in 2015.
Perhaps the answer lies in historic meteorological data of the area. In 2015 the Alps experienced a prolonged, record-breaking heatwave, which led to very many high-altitude rockfalls in a number of areas, including in the Mont Blanc massif, as rock-wall permafrost warmed. Data also show that since then there has been a big increase in days when the average temperatures in the Swiss Alps is above 0 °C. These so-called “positive degree days” are known to lead to increased glacial melt.
All of these findings support the idea that the onset of seasonal seismic activity is linked to climate change-induced increases in meltwater and alterations in flow paths. Simon explains that rock collapses can alter the pathways that water follows as it infiltrates into the ground. Combined with increases in meltwater, this can lead to pore-pressure changes that increase seismicity and trigger it in new places.
These small earthquakes in the Mont Blanc massif are unlikely to trouble local communities. But the researchers did find that at times the seismic hazard – an indicator of how often and intensely the earth could shake in a specific area – rose by nearly four orders of magnitude, compared with pre-2015 level. They warn that similar processes in glaciated areas that experience larger earthquakes than the Alps, such as the Himalayas, might be less gentle.
Climate change is also altering water-flow patterns by increasing the intensity of extreme weather events and heavy rainfall. And there is already evidence that such extreme precipitation can influence seismic activity.
In 2020 Storm Alex brought record-breaking rainfall to the south-east of France, with some areas seeing more than 600 mm in 24 hours. In the following 100 days 188 earthquakes were recorded in the Tinée valley, in south-eastern France. Although all were below two in magnitude, that volume of microquakes would usually be spread over a five-year period in the region. A 2024 analysis carried out by seismologists in France concluded that increased fluid pressure from the extreme rainfall caused a stressed fault system to slip, initiating a seismic swarm – a localized cluster of earthquakes, without a single “mainshock”, that take place over a relatively short period of days, months or years (see figure 1).
French seismologist Laeticia Jacquemond and colleagues have developed a model showing the sequence of mechanisms that likely trigger a seismic swarm, which is a localized cluster of earthquakes. The sequence starts with abrupt and extreme rainfall, like 2020’s Storm Alex. Thanks to open fault zones, a lot of rainfall is transmitted deep within a critically stressed crust. The fluid invasion through the fractured medium then induces a poroelastic response of the crust at shallow depths, triggering or accelerating a seismic slip on fault planes. As this slip propagates through the fault network, it pressurizes and stresses locked asperities (areas on an active fault where there is increased friction), predisposed to rupture, and initiates a seismic swarm.
There have been other examples in Europe of seismic activity linked to extreme rainfall. For instance, in September 2002 a catastrophic storm in western Provence in southern France, with similar rainfall levels as Storm Alex, triggered a clear and sudden increase in seismic activity, a study concluded. While another analysis found that an unusual series of 47 earthquakes over 12 hours in central Switzerland in August 2005 was likely caused by three days of intense rainfall.
According to Marco Bohnhoff from the GFZ Helmholtz Centre for Geosciences in Potsdam, Germany, the link between fluid infiltration into the ground and seismicity is well understood – from fluid injection for oil and gas production, to geothermal development and heavy rainfall. “The pore pressure is increased if there is a small load on top, enforced by water, and that changes the pressure conditions in the underground, which can release energy that is already stored there,” Bohnhoff explains.
A good example of this is the Koyna Dam, one of India’s largest hydroelectric projects, which consists of four dams. Every year during the monsoon season the water level in the reservoir behind the dams increases by about 20–25 m, and with this comes an increase in seismic activity. “After the rain stops and the water level decreases, the earthquake activity stops,” says Bohnhoff. “So, the earthquake activity distribution nicely follows the water level.”
According to Bohnoff, anything that increases the pressure underground could trigger earthquakes. But he has also been studying the effect of another consequence of climate change: sea-level rise.
Undisputed and accelerating, sea-level rise is driven by two main effects linked to climate change: the expansion of ocean waters as they warm, and the melting of land ice, mainly the Antarctic and Greenland ice sheets. According to the World Meteorological Organization, sea levels will rise by half a metre by 2100 if emissions follow the Paris Agreement, but increases of up to two metres cannot be ruled out if emissions are even higher.
As ocean waters increase, so does the load on the underground. “This will change the global earthquake activity rate,” says Bohnhoff. In a study published in 2024, Bohnhoff and colleagues found that sea-level rise will advance the seismic clock, leading to more and in some cases stronger earthquakes (Seismological Research Letters 95 2571).
“It doesn’t mean that all of a sudden there will be earthquakes everywhere, but earthquakes that would have occurred sometime in the future will occur sooner,” he says. “We’re changing the regularity of earthquakes.” The risk created by this is greatest in coastal mega-cities, located near critical fault zones, such as San Francisco and Los Angeles in the US; Istanbul in Turkey; and Tokyo and Yokohama in Japan.
The findings cannot be used to predict individual earthquakes – in fact, it is very difficult to predict how much the seismic clock will advance, as it depends on the amount of sea-level rise. But there are faults around the world that are critically stressed and close to the end of their seismic cycle.
“Faults that are very, very close to failure, where basically there would be an earthquake, say in 100 years or 50 years, they might be advanced and that might occur very soon,” he explains.
Another significant geological hazard linked to climate change and heavy rainfall is volcanic activity. In December 2021 there was devastating eruption of Mount Semeru, on the Indonesian island of Java. “There was a really heavy rainfall event and that caused the collapse of the lava dome at the summit,” says Jamie Farquharson, a volcanologist at Niigata University in Japan.
This led to a series of eruptions, pyroclastic flows and “lahars” – devastating flows of mud and volcanic debris – that killed at least 69 people and damaged more than 5000 homes. Although it is challenging to attribute this specific event to climate change, Farquharson says that it is a good example of how global warming-induced heavy rainfall could exacerbate volcanic hazards.
Farquharson and colleagues noticed links between ground deformations and rainfall at several volcanoes. “We started seeing some correlations and thought why shouldn’t we? Because from a rock mechanics point of view, these volcanoes would be more prone to fracturing and other kinds of failure when the pore pressure is high,” says Farquharson. “And one of the easiest ways of increasing pore pressure is by dumping a load of rain onto the volcano.”
Such rock fracturing can open new pathways for magma to propagate towards the surface. This can happen deep underground, but also near the surface, for instance by causing a chunk of the flank to slide off a volcano. As with earthquakes, these changes could alter the timing of eruptions. For volcanoes that might be primed for an eruption, where the magma chamber is inflating, extreme rainfall events might hasten an eruption. But as Farquharson explains, such rainfall events “could bring something that was going to happen at an unspecified point in the future across a tipping point”.
A few years ago Farquharson, together with atmospheric scientist Falk Amelung of the University of Miami in the US, published a study showing that if global warming continues at current rates, rainfall-linked volcanic activity – such as dome explosions and flank collapses – will increase at more than 700 volcanoes around the globe (R. Soc. Open Sci. 9 220275).
To explore the impact of rainfall, Farquharson and Amelung analysed decades of reports on volcanic activity from the Smithsonian’s Global Volcanism Program. This showed that heavy or extreme rainfall has been linked to eruptions and other hazards, such as lahars at at least 174 volcanoes (see figure 2).
There are 1234 volcanoes on land that have been active in the Holocene, the current geological epoch, which began around 12,000 years ago. The geologists used nine different models to explore how climate change might alter rainfall at these volcanos. They found that 716 of these volcanoes will experience more extreme rainfall as global temperatures continue to rise. The models did not agree on whether rainfall will become more or less extreme at 407 of the volcanoes, and the remaining 111 are in regions expected to see a drop in heavy rain.
Jamie Farquharson and colleagues are studying how heavy rainfall drives a range of volcanic hazards. The colours on the map reflect the “forced model response” (FMR) – the percentage change of heavy precipitation for a given unit of global warming. Serving as a proxy for the likelihood of extreme rainfall events, the value of FMR was averaged from nine different “general circulation models” (i.e. global climate models). FMR is shown here as the percentage rise or fall in extreme rainfall projected by the models for every degree of global warming between 2005 and 2100 CE. The darkest reds show areas that will experience a 20% or more decrease in extreme rainfall for each degree of warming, while the darkest blues highlight areas which will experience a 20% or more increase in extreme rainfall per degree of warming. The figures were made with CMIP5 model data, which assumes a “high emissions” scenario. Their results suggest that if global warming continues unchecked, the incidence of primary and secondary rainfall-related volcanic activity – such as dome explosions or flank collapse – will increase at more than 700 volcanoes around the globe.
Volcanic regions where heavy rainfall is expected to increase include the Caribbean islands, parts of the Mediterranean, the East African Rift system, and most of the Pacific Ring of Fire.
In fact, volcanic hazards in many of these regions have already been linked to heavy rainfall. For instance, in 1998 extreme rainfall in Italy led to devastating debris flows on Mount Vesuvius and Campi Flegrei, near Naples, killing 160 people.
Elsewhere, rainfall has sparked explosive activity at Mount St Helens, in the Cascade Mountains of Canada and the western US. Other volcanoes in this range, which is part of the Ring of Fire, put major population centres at significant lahar risk, due to their steep slopes. In both the Caribbean and Indonesia – the world’s most volcanically active country, heavy rainfall has triggered explosive activity and eruptions at active volcanoes.
Farquharson and Amelung warn that if heavy rainfall increases in these regions as predicted, it will heighten an already considerable threat to life, property and infrastructure. As we enter a new era of much higher resolution climate modelling, Farquharson hopes that we will “be able to get a much better handle on exactly which [volcanic] systems could be affected the most”. This may enable scientists to better estimate how hazards will change at specific geographical locations.
Scientists are also concerned about what will happen to volcanoes currently buried under ice as the climate warms. Through modelling work and studying volcanoes that sat below the Patagonian Ice Sheet during and at the end of the last ice age, Brad Singer, a geoscientist at the University of Wisconsin-Madison in the US, and colleagues have been exploring the impact of deglaciation on volcanic processes.
They found that ice loss can lead to an increase in large explosive eruptions. This occurs because as the ice melts, the weight on the volcano drops, which allows magma to expand and put pressure on the rock within the volcano. Also, as pressure from the ice reduces, dissolved volatile gases like water and carbon dioxide separate from the magma to form gas bubbles. This further increases the pressure in the magma chamber, which can promote an eruption.
But each volcano responds differently to ice. Singer’s team has been dating and studying the chemical composition of lava flow samples from South America, to track the behaviour of volcanoes over tens of thousands of years, through the build-up of the ice and after deglaciation.
The Patagonian Ice Sheet began to melt very rapidly about 18,000 years ago and by about 16,000 years ago it was gone. “We develop a timeline and put compositions on that timeline and look to see if there were any changes in the composition of the magmas that were erupting as a function of the thickness of the ice sheet,” explains Singer. “We are finding some really interesting things.”
The Puyehue-Cordón Caulle and Mocho-Choshuenco volcanic complexes in southern Chile both erupt rhyolitic magmas. But they were not producing this type of magma before the ice retreated, as Singer and colleagues found (GSA Bulletin 136 5262) (see figure 3).
Geologist Brad Singer and colleagues are studying how glaciers and ice sheets impact the evolution of volcanoes, to develop a “lava-fed delta” model. (a) The researchers studied basaltic andesites in the Río Blanco river in Argentina (Arb). A fine-grained extrusive igneous rock that forms when volcanic magma erupts and crystallizes outside of the volcano, basaltic andesites were impounded by the Patagonian Ice Sheet roughly 26,000 years ago. Here they formed cliffs that were then occupied by the Patagonian Ice Sheet at 1500–1700 m above sea level between 26,000 and 20,000 years ago. Ice on top of the edifice should have been comparatively thinner than in the surrounding valleys. (b) As the ice sheet retreated between 18,000 and 16,000 years ago, dacite – a fine-grained volcanic rock formed by rapid solidification of lava that is high in silica and low in alkali metal oxides – from the Río Truful river in Chile (Drt) flowed onto it. (c) Lava is channelized as it melts the ice to form a lava-fed delta. (d) Dacite flows through the ice and to its base.
“We don’t know for sure that [magma change] is attributable to the glaciation, but it is curious that immediately following the deglaciation we start to see the first appearance of these highly explosive rhyolitic magmas,” says Singer. The volcanologists suspect that the ice sheet reduced eruptions at these volcanos, leading magma to accumulate over thousands of years. “That accumulated reservoir can evolve into this explosive dangerous magma type called rhyolite,” Singer adds.
But that didn’t always happen. The Calbuco volcano, in southern Chile, has always erupted andesite, an intermediate-composition magma. “It’s never erupted basalt, it’s never erupted rhyolite, it’s erupting andesite, regardless of whether the ice is there or not,” explains Singer.
There are also differences in how quickly volcanoes reacted to the deglaciation. At Mocho-Choshuenco, for example, there was a large rhyolite eruption about 3000 years after the loss of ice. Singer suspects that the delay “reflects the time that it took to exsolve the volatiles from the rhyolite”. But at the nearby, very active Villarrica volcano, there was no such delay. It experienced a huge eruption 16,800 years ago, almost immediately after the ice disappeared.
Volcanic activity from melting ice sheets, due to current climate change, is probably not a direct hazard to people. But below the West Antarctic Ice Sheet sits the West Antarctic Rift – a system that is thought to contain at least 100 active volcanoes.
A major contributor to global sea-level rise, the West Antarctic Ice Sheet is particularly vulnerable to collapse as temperatures rise. If they become more active and explosive, the volcanoes of the West Antarctic Rift System could accelerate ice melting and sea-level rise.
“The melting of the West Antarctic Ice Sheet could remove the surface load that’s preventing eruptions from occurring,” says Singer. Such eruptions could bring lava and heat to the base of the ice sheet, which is dangerous because melting at the base can cause the ice to move faster into the ocean. The resulting rising sea levels could go on to advance the seismic clock and trigger earthquakes.
In the long run, increased volcanic activity will impact global climate, with the cumulative effect of multiple eruptions contributing to global warming thanks to a build-up of greenhouse gases. Essentially, a positive feedback loop is created, as melting ice caps, helped by volcanoes, could lead to more earthquakes. Managing the Earth’s warming and protecting the world’s remaining glaciers and ice sheets is therefore more crucial than ever.
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The near and far sides of the Moon are very different in their chemical composition, their magmatic activity and the thickness of their crust. The reasons for this difference are not fully understood, but a new study of rocks brought back to Earth by China’s Chang’e-6 mission has provided the beginnings of an answer. According to researchers at the Chinese Academy of Sciences (CAS) in Beijing, who measured iron and potassium isotopes in four samples from the Moon’s gigantic South Pole-Aitken Basin (SPA), the discrepancy likely stems from the giant meteorite impact that created the basin.
China has been at the forefront of lunar exploration in recent years, beginning in 2007 with the launch of the lunar orbiter Chang’e-1. Since then, it has carried out several uncrewed missions to the lunar surface. In 2019, one of these, Chang’e-4, became the first craft to touch down on the far side of the Moon, landing in the SPA’s Von Kármán crater. This 2500-km-wide feature extends from the near to the far side of the Moon and is one of the oldest known impact craters in our solar system, with an estimated age of between 4.2 and 4.3 billion years old.
Next in the series was Chang’e-5, which launched in November 2020 and subsequently returned 1.7 kg of samples from the near side of the Moon – the first lunar samples brought back to Earth in nearly 50 years. Hot on the heels of this feat came the return of samples from the far side of the Moon aboard Chang’e-6 after it launched on 3 May 2024.
When scientists at the CAS Institute of Geology and Geophysics and colleagues analysed these samples, they found that the ratio of potassium-41 to potassium-39 is greater in the samples from the SPA basin than in samples from the near side collected by Chang’e-5 and NASA’s Apollo missions. According to study leader Heng-Ci Tian, this potassium isotope ratio is a relic of the giant impact that formed this basin.
Tian explains that the impact created such intense temperatures and pressures that many of the volatile elements in the Moon’s crust and mantle – including potassium – evaporated and escaped into space. “Since the lighter potassium-39 isotope would more readily evaporate than the heavier potassium-41 isotope, the impact produced this greater ratio of potassium-41 to potassium-39,” says Tian. He adds that this explanation is also supported by earlier results, such as Chang’e 6’s discovery that the mantle on the far side contains less water than the near side.
Before drawing this conclusion, the researchers, who report their work in the Proceedings of the National Academy of Sciences, needed to rule out several other possible explanations. The options they considered included whether irradiation of the lunar surface by cosmic rays could have produced an unusual isotopic ratio, and whether magma melting, cooling and eruptive processes could have changed the composition of the basaltic rocks. They also examined the possibility that contamination from meteorites could be responsible. Ultimately, though, they concluded that these processes would have had only negligible effects.
Tian says the team’s work represents the first evidence that an impact event of this size can volatilize materials deep within the Moon. But that’s not all. The findings also offer the first direct evidence that large impacts play an important role in transforming the Moon’s crust and mantle. Fewer volatiles, for example, would limit volcanic activity by suppressing magma formation – something that would explain why the lunar far side contains so few of the vast volcanic plains, or maria, that appear dark to us when we look at the Moon’s near side from Earth.
“The loss of moderately volatile elements – and likely also highly volatile elements – would have suppressed magma generation and volcanic eruptions on the far side,” Tian says. “We therefore propose that the SPA impact contributed, at least partially, to the observed hemispheric asymmetry in volcanic distribution.”
Having hypothesized that moderately volatile elements could be an effective means of tracing lunar impact effects, Tian and colleagues were eager to use the Chang’e-6 samples to investigate how such a large impact affects the shallow and deep lunar interior. But it wasn’t all smooth sailing. “A major technical challenge was that the Chang’e‑6 samples consist mainly of fine-grained materials, making it difficult to select large individual grains,” he recalls. “To overcome this, we developed an ultra‑low‑consumption potassium isotope analytical protocol, which ultimately enabled high‑precision potassium isotope measurements at the milligram level.”
The current results are preliminary, and the researchers plan to analyse additional moderately volatile element isotopes to verify their conclusions. “We will also combine these findings with numerical modelling to evaluate the global-scale effects of the SPA impact,” Tian tells Physics World.
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A little more than a year after dismissing the moon as a “distraction,” Elon Musk says SpaceX will focus on lunar settlement before sending humans to Mars.
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