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Scientists are pioneering a new approach to designing electrolytes for more energy-efficient and less carbon-intensive electrochemical processes. They hope to improve electrolyte performance in applications such as iron production for steel.

Researchers have developed a set of hexagon-shaped robotic components that can be snapped together into larger and larger structures. Each one of the component hexagons is made of rigid plates that serve as its exoskeleton. Driven by electricity, the plates can change their shape, shifting from long and narrow to wide and flat at high speed. The combined structures are capable of jumping four times their own body height, then can shape-shift to roll extremely fast, or use multimodal actuation to crawl through confined spaces.

The robotic components were developed at the Max-Planck-Institute for Intelligent Systems (MPI-IS). The modules are made of six lightweight rigid plates made from glass fiber that form a hexagon. Magnets embedded into the plates allows for quick connection to other components as well as providing a shared electrical ground between the modules.

Individual HEXEL modules combine soft artificial muscles with rigid components for fast and large motions. Credit: Zachary Yoder / MPI-IS Ellen Rumley / MPI-IS

The design team integrated artificial “muscles” into the inner joints of the hexagons, called hydraulically amplified self-healing electrostatic (HASEL) muscles. Applying a high voltage to the module causes the muscle to activate, rotating the joints of the hexagon and changing its shape from long and narrow to wide and flat.

“Combining soft and rigid components in this way enables high strokes and high speeds. By connecting several modules, we can create new robot geometries and repurpose them for changing needs,” said  Ellen Rumley, a visiting researcher from the University of Colorado Boulder, in a press release from MPI-IS. Rumley and Zachary Yoder, who are both Ph.D. students working in the Robotic Materials Department, are co-first authors of a new paper, “Hexagonal electrohydraulic modules for rapidly reconfigurable high-speed robots,” published in Science Robotics.

The modules are reconfigurable, with an easy process of attaching or detaching the modules. Chains of modules can be rapidly connected and can operate from one voltage source. The modules can each have their own behaviors, which allows for various operations.

The team created a video to show the various configurations and behaviors that can be created with HEXEL modules. The modules can be seen rolling, dancing, jumping, crawling, and many other motions.  

“In general, it makes a lot of sense to develop robots with reconfigurable capabilities,” said Yoder. “It’s a sustainable design option – instead of buying five different robots for five different purposes, we can build many different robots by using the same components. Robots made from reconfigurable modules could be rearranged on demand to provide more versatility than specialized systems, which could be beneficial in resource-limited environments.”

The post Shape-Shifting Robots Mimic Muscle Movements appeared first on Universe Today.

I hate writing about cancellations like this day after day, but I see it as part of my brief to let people know what’s going on.  This time we have writer Elisa Albert canceled—or rather, a panel she was scheduled to be on was canceled—because she was a “Zionist”, even though she wasn’t going to talk about Judaism. (To a very large extent, “Zionist” has become a euphemism for “Jews,” as nearly all Jews in America are Zionists—i.e., support the existence of Israel—and the only anti-Zionists I know who aren’t really anti-Semites are some Orthodox Jews, mostly in Israel.)

But I digress. The Free Press article below (click headline to read, or see it archived here), writer Elisa Albert was canceled because she was a Zionist Jew, even though the panel she was supposed to be on—a discussion of four women’s books at the University of Albany’s New York State Writer’s Festival—wasn’t going to be about Zionism.  This is the kind of cancelation that seems to me to presage a growing wave of anti-Semitism in America.  The story is below:

Excerpts (the author is Joe Nocera, and the subject, Elisa Albert, is in the photo above). Bolding is mine:

For the last seven years, the New York State Writers Institute has held an annual book festival at the University at Albany. It’s where notable authors come together and discuss big ideas like climate change, feminism, and immigration. But this year, the festival, which was held on Saturday, was disrupted because two authors refused to discuss their books with the panel’s moderator. Why? Because she is a “Zionist.”

The Zionist in question was Elisa Albert, a 46-year-old progressive feminist author whose novels—she’s written three of them—are dark comedies about subjects like modern motherhood and fame. She had agreed to moderate the panel months earlier, and she was looking forward to it. “I was going to be like a game-show host,” she told me in a phone interview. “Congenial and respectful. Have some fun in the process.”

But on Thursday afternoon, just as she was preparing to read the books by her fellow panelists, she received an email out of the blue from Mark Koplik, the assistant director of the Writers Institute. “Basically, not to sugar coat this, Aisha Gawad and Lisa Ko don’t want to be on a panel with a ‘Zionist,’ ” he wrote in an email shared with The Free Press. “We’re taken by surprise, and somewhat nonplussed, and want to talk this out.”

Albert was stunned. Though she described herself to me as “a proud Jew” who has been fiercely outspoken since October 7, there had been no hint of trouble in the months leading up to the festival. And the panel’s topic—“Girls Coming of Age”—seemed utterly benign.

But Aisha Abdel Gawad, a Muslim writer in her mid-30s whose novel Between Two Moons was published last year to considerable acclaim, and Lisa Ko, whose first book, The Leavers, was nominated for a National Book Award, were no longer willing to share the stage with a Jew who supports Israel. Unsure how to proceed, Koplik and the institute’s director Paul Grondahl contacted the third writer on the panel, the crime novelist Emily Layden who, according to Albert, told them she was dropping out as well because she wanted to avoid the controversy. (Gawad and Ko did not respond to emails, sent both to them and their literary agents, requesting comment.A request for comment was also emailed to Layden’s publicist, who did not respond.)

At that point the Writers Institute and the University at Albany, which administers the program, had to make a choice: They could publicly condemn the antisemitism displayed by Gawad and Ko and make sure the festival-goers were aware of what had happened. In a series of phone calls Thursday afternoon, Albert says she tried to convince them to do just that. Or they could capitulate to the bigotry by trying to sweep the whole thing under the rug, and listing the cancellation on the festival’s website as the result of “unforeseen circumstances.”

The institute chose the latter course.. . .

Albert suggested that they keep the panel, showing three empty chairs, but director Grondahl said that wouldn’t be fair if attendees were expecting a full panel. I can see the point there, but surely the Institute should have given Albert a chance to speak on her own: she even could have spoken about her cancellation. But it didn’t fly.  The article goes on to discuss the problems currently facing Jewish writers (I simply can’t imagine any adult fiction being written that is sympathetic to Jews or Israel).  The issue was highlighted this year in a NYT op-ed column by James Kirchick, who gives examples of “anti-Zionism” in the literary world. Click below to read, or find it archived here: Kirchick’s thesis is that Jews have a hard time making it in the literary world unless they’re willing to denounce Israel.

There has been some pushback. For one thing, banning someone from a state-sponsored panel because of their religious views is probably illegal:

In addition to failing to uphold its moral responsibility in the face of antisemitism, legal experts told me that the New York State Writers Institute may well have violated the law.

David Schizer, the dean emeritus of Columbia Law School—and the co-head of Columbia’s Task Force on Antisemitism—told me that because the Writers Institute is part of the University at Albany, which is state-funded, it must adhere to laws that outlaw discrimination. And the Department of Education has been clear that boycotting someone because of their religion is in violation of Title VI of the 1964 Civil Rights Act. “If a university that takes government money says it will not have panels with Jews, that is clearly a problem,” he told me. “That is clearly illegal.”

He added, “If an institution formally condemns the antisemitism and the exclusion of Jews from a panel, that could have gone a long way to mitigate the issue.” The institute could also have let Albert go on by herself, he said. Both options are precisely what Albert said she had asked the directors of the Writers Institute to do, but they refused.

This sentiment was echoed by the head of the whole SUNY system:

On Saturday, as the festival was taking place, King sent an angry email to Albany’s president, Havidán Rodríguez, which Albert obtained and showed to The Free Press. Expressing shock at learning “from media coverage” about the canceled panel, he said the festival should have issued “an unequivocal statement that bigotry and antisemitism are absolutely unacceptable and the panel would proceed with or without these people participating.” He added: “SUNY’s content-neutral commitment to free expression and our fidelity to the protections guaranteed by Title VI of the Civil Rights Act of 1964 would have led to a response along the lines the author suggested. As I wrote in a recent public letter and have emphasized to all SUNY campus presidents: Antisemitism is antisemitism whatever ‘code words’ are used, including if ‘Zionist’ is intended to mean the same thing as ‘Jewish.’ ”

King concluded: “I believe the only appropriate response at this point is to ensure that Ms. Albert is afforded the opportunity to have her views expressed to the greatest extent possible, whether that is during the remaining hours of the festival or at a subsequent event held by the Institute.”

As for Albert, she took it like a mensch, though she’s not sure she’ll participate in the Writers festival any more:

. . . But she imagined a different way this could have played out—one in which Gawad and Ko had stayed on the panel instead of walking away.

“Had they been even slightly more evolved thinkers, I can easily imagine a scenario in which they might have chosen to come to Albany with open minds and hearts,” she said. “Perhaps they might have hopped that train to Albany with some awareness that, while the moderator of their panel is a fellow novelist whose lived experience and history and inheritance and education and understanding and fear and trauma and grief and shame are profoundly different from their own, there might still be something—no matter how minor, or how seemingly banal—to learn from me. Perhaps, in my wishful scenario, they might even have found it within themselves to hold space for difference, and to maybe, just maybe, grow ever so slightly in the process. Perhaps, were they just that smallest bit more open-minded, they would have managed to teach me something in turn.

“Anyway,” she concluded, “I’m sorry we won’t have the chance to meet and talk, because it would have been super cool to understand them better. And, dare to dream, I could have offered them some understanding of myself in turn.”

Bravo for Albert, and boos to the hateful Aisha Gawad and Lisa Ko, as well as the cowardly Emily Laden!  I sympathize with Albert even more because my own children’s book, initially met with enthusiasm by a respected editor and a famous illustrator, wasn’t published because the editor wouldn’t dare show it to publishers. The problem: it was a fantasy book about cats in India, and I am not Indian. I had no credibility to write about Indian cats because. . . I was a white man!   (Are there any publishers out there with guts? If so, I have a book to sell!)

Remember, this was a literary festival, and in publishing all points of view are considered by good editors. To cancel a book discussion because one of the authors supports Israel is simply beyond the pale. But these days it seems almost normal. This normalization of anti-Zionism is, frankly, scary.

Here’s a short clip of Albert at that Festival in 2015.  She seems “cool” and funny:

The tiered umbrella is one of Thailand's oldest and most sacred ornamental symbols. Constructing one of these ornate pieces, also called chatras, can take master artisans up to six months. However, researchers demonstrate a technique for constructing seven-tiered umbrellas using high-powered lasers, which dramatically reduces the production time. Employing carbon dioxide lasers, they were able to fashion umbrellas from stainless steel in a matter of days while preserving their intricate beauty.

A mysterious type of iron-rich magma entombed within extinct volcanoes is likely abundant with rare earth elements and could offer a new way to source these in-demand metals, according to new research. Rare earth elements are found in smartphones, flat screen TVs, magnets, and even trains and missiles. They are also vital to the development of electric vehicles and renewable energy technologies such as wind turbines.

Researchers have found a way to use a component of glycerol to produce bio-based propylene.

A new study reveals that artificial intelligence chatbots, such as ChatGPT, may be almost as effective as consulting a doctor for advice on low back pain.

Astronomers have observed the atmosphere of a hot and uniquely inflated exoplanet using NASA's James Webb Space Telescope.

With strong bactericidal properties, graphene has the potential to become a game changer in the fight against antibiotic-resistant bacteria. So far there have been no efficient ways to control these properties -- and thus no way to make use of graphene's potential in healthcare. Now researchers have solved the problem by using the same technology found in an ordinary fridge magnet. The result of which, is an ultra-thin acupuncture-like surface that can act as a coating on catheters and implants -- killing 99.9 percent of all bacteria on a surface.

Ammonia (NH3) can be decomposed to produce hydrogen gas without releasing CO2. The ease of transport and high hydrogen density make it valuable for the green energy industry. A drawback of using NH3 is that it requires very high temperatures for decomposition reactions. Researchers have now presented a surface protonics-assisted method for the on-demand production of green hydrogen from ammonia using an electric field and Ru/CeO2 catalyst.

In most vertebrates, a pattern of chemical marks on the genome is a reliable indicator of age, but in axolotls this clock seems to stop after the first four years of life

New research is revealing that common sense is a lot more idiosyncratic than we thought, with important implications for tackling political polarisation and the future of AI

Artificial coastlines, including human-made dikes and other engineered constructions, can help prevent erosion and protect from storms and flooding. However, ecological functions remain unprotected from many of these structures. So researchers in China have investigated the use of specialized types of cement. The team started with a limestone and clay cement that hardens underwater and then added polyacrylamide and chitosan. The two treatments were mixed into the cement to form the hardened substrate, and they were sprayed onto previously hardened cement as a surface treatment. After two days, biofilm was found active and growing well on the surface-treated samples.

UPDATE: As Malgorzata points out in a comment below citing an Algemeiner article, Whitmer did defend her attorney general, which constitutes taking sides against the odious Rashida Tlaib. A quote from the Algemeiner:

Michigan Gov. Gretchen Whitmer (D) issued a statement in defense of the state’s Jewish Attorney General Dana Nessel over what she called “antisemitic” suggestions by US Rep. Rashida Tlaib (D-MI) that Nessel’s office harbored “biases” against pro-Palestinian activists.

“The suggestion that Attorney General Nessel would make charging decisions based on her religion as opposed to the rule of law is antisemitic,” Whitmer wrote on Monday. “Attorney General Nessel has always conducted her work with integrity and followed the rule of law. We must all use our platform and voices to call out hateful rhetoric and racist tropes.”

The statement came one day after Whitmer, during an interview with CNN anchor Jake Tapper, initially refused to weigh in on the quarrel between Nessel and Tlaib, who suggested that the attorney general has not treated anti-Israel protesters impartially because of her Jewish faith.

Whitmer, having corrected herself, is back on the side of the angels again. If only she were the Democratic candidate for President!

Although Gretchen Whitmer, the governor of Michigan, identifies herself as a “progressive” Democratic, to me she seems progressive in the right way: she’s trying to fix the problems in her state with tangible legislation. You can see the list of her accomplishments here, and A. B. Stoddard, writing in The Bulwark last year, called Whitmer 52, “one of the most experienced, exciting, and winning Democrats in the country.” I agree with nearly all of her policies—although she’s a bit too soft on illegal immigration—and that’s why I wanted Whitmer to be the Democratic candidate for President. (Importantly, she also governs a swing state.) She has accomplished stuff in a bipartisan climate, and I’d feel a lot better with her at the helm than with Kamala Harris.

But when Kamala Harris was anointed by the Democratic Party to be its candidate, Whitmer refused to be a candidate. That’s very sad, because, given her record, Harris doesn’t hold a candle to her.  And, of course, if Harris wins this time she’ll surely be the Democratic candidate in 2028 unless she screws up big time, so that Whitmer would have to wait eight more years if she wanted to run America.

So I was sad to see this article in Politico; the title tells the tale (click to read):

An excerpt:

Michigan Gov. Gretchen Whitmer declined to take sides in a debate between Michigan Attorney General Dana Nessel and Rep. Rashida Tlaib (D-Mich.) over almost a dozen University of Michigan students charged for pro-Palestinian protests.

“I’m not going to get in the middle of this argument that they’re having,” Whitmer said on Sunday in an interview with Jake Tapper on CNN’s “State of the Union.”

“I can just say this. We do want to make sure that students are safe on our campuses and we recognize that every person has the right to make their statement about how they feel about an issue, a right to speak out,” Whitmer added. “And I’m going to use every every lever of mine to ensure that both are true.”

Nessel, Michigan’s first Jewish Attorney General, recently charged 11 University of Michigan students for pro-Palestinian demonstrations. Most were charged for refusing to vacate the encampments on campus in May, according to the Detroit Metro Times.

Nessel defended the state’s decision to charge these students saying, “Conviction in your ideals is not an excuse for violations of the law” and “what is a crime anywhere else in the city remains a crime on university property.”

Tlaib — the only Palestinian American in Congress and a strong critic of Israel — criticized Nessel for this decision in an interview with the Detroit Metro Times. She said: “It seems that the attorney general decided if the issue was Palestine, she was going to treat it differently, and that alone speaks volumes about possible biases within the agency she runs.”

. . . When CNN’s Jake Tapper initially asked about the back and forth between Nessel and Tlaib, Whitmer declined to directly defend or criticize the state’s attorney general, responding that all she could say was “our Jewish community is in pain, as is our Palestinian and Muslim and Arab communities in Michigan.”

“I know that seeing the incredible toll that this war has taken on both communities has been really, really challenging and difficult. And my heart breaks for so many,” Whitmer said. “But as governor, my job is to make sure that both these communities are protected and respected under the law in Michigan. And that’s exactly what I’m going to stay focused on.”

Well, it seems to me that Whitmer should be supporting her own attorney general, or at least saying, that “Nessel brought charges against the protesters and we need to let those charges play out in the legal system”. But she went a bit further with her “whataboutism”, not recognizing, apparently, that free speech is not the same thing as disrupting a campus and violating the law.

That said, Whitmer is clearly between a rock and a hard place. While her attorney general brought charges against pro-Palestinian students, one of her state’s representatives, the odious Tlaib, is supported by many Michigan Palestinians or their supporters. So I can’t hold this against her very hard. While I dislike politicans that are pure pragmatists, Whitmer is not really a pragmatist.  She takes stands, and is known for her potty mouth, which I like.  A bit of that is evident in the video below.

Here’s her speech at the Democratic National Convention, without any nattering about coconuts or inappropriate laughter.  Whitmer of course had to support Harris in her speech, but believe me, I’d rather check a box for Whitmer than for Harris in November.  Had there been debates to choose a candidate, Whitmer would, I think, have come out on top.  This is a tough, accomplished women who has no problem articulating her positions.

As promised, the audiobook for Waves in an Impossible Sea, read by Christopher Grove, has finally come available. You can find it on Audible and on many other platforms. (Click here to order the audibook, hardback, or e-book.)

To help make the text easier to follow, I’ve put the 50+ figures, the 6 tables, and the glossary on-line. You might, for instance, choose to have them open on your phone for easy reference while you’re listening. (The endnotes are also there too, although my understanding is that Mr. Grove won’t be mentioning them as he reads, so you may need the text to make them useful.)

There are additional resources for readers already up on this website, supplementing the book, and more are coming soon, so please make use of them. Also feel free to ask me questions if you find yourself confused — and please don’t be embarrassed to do so, because the universe is confusing… even to physicists. No question is too simple; in fact, the simple ones (what is empty space? what’s a particle? why don’t we feel the Earth’s motion?) are often the hardest to answer.

When we talk about reducing carbon release in order to slow down and hopefully stop anthropogenic global warming much of the focus is on the energy and transportation sectors. There is a good reason for this – the energy sector is responsible for 25% of greenhouse gas (GHG) emissions, while the transportation sector is responsible for 28% (if you separate out energy production and not include it in the end-user category). But that is just over half of GHG emissions. We can’t ignore the other half. Agriculture is responsible for 10% of GHG emissions, while industry is responsible for 23%, and residential and commercial activity 13%. Further, the transportation sector has many components, not just cars and trucks. It includes mass transit, rail, and aviation.

Any plan to deeply decarbonize our civilization must consider all sectors. We won’t get anywhere near net zero with just green energy and electric cars. It is tempting to focus on energy and cars because at least there we know exactly what to do, and we are, in fact, doing it. Most of the disagreement is about the optimal path to take and what the optimal mix of green energy options would be in different locations. For electric vehicles the discussion is mostly about how to make the transition happen faster – do we focus on subsidies, infrastructure, incentives, or mandates?

Industry is a different situation, and has been a tough nut to crack, although we are making progress. There are many GHG intensive processes in industry (like steel and concrete), and each requires different solutions and difficult transitions. Also, the solution often involves electrifying some aspect of industry, which works only if the energy sector is green, and will increase the demand for clean energy. Conservative estimates are that the energy sector will increase by 50% by 2050, but if we are successful in electrifying transportation and industry (not to mention all those data centers for AI applications) this estimate may be way off. This is yet another reason why we need an all-of-the-above approach to green energy.

Let’s focus on agriculture and aviation, which are also considered difficult  sectors to decarbonize, starting with agriculture. Often the discussion on agriculture focuses on meat consumption, because the meat industry is a very GHG intensive portion of the agricultural sector. There is a good argument to be made for moderating meat consumption in industrialized nations, both from a health and environmental perspective. This doesn’t mean banning hamburgers, and it is often strawmanned, but some voluntary moderation would be a good thing. There is also some mitigation possible – yes, I am talking about capturing cow farts.

There are also efforts to shift farming from a net carbon emitter to a net carbon sequester. A recent analysis finds that this is plausible, by switching to certain farming practices that could be a net financial benefit to farmers and help maintain farming productivity in the face of warming. This includes the use of cover crops, combining farming with forestry, and using no-till methods of farming. With these methods farms can turn into a net carbon sink.

Obviously this is a temporary mechanism, but could help buy us time. Right now we are doing the opposite – cutting down forest to convert to farmland, and eliminating carbon sinks. Farming forests, or incorporating more trees into farmland, can help reverse this process.

What about aviation? This is also a difficult sector, like industry, because we don’t have off-the-shelf solutions ready to go. A recent report, however, outlines steps the industry can take over the next five years that can put it on track to reach net zero by 2050. One step, which I had not heard of before, is deploying a global contrail avoidance system. Contrails are vapor trails that form when the hot jet exhaust mixes with cool moist air. These act like artificial cirrus clouds, which have a mild cooling effect during the day but a much more significant warming effect at night (by trapping heat). Contrails are responsible for 35% of the aviation industry’s warming effect. Using AI and satellite data, pilots can be directed to routes that would minimize contrail formation.

They also recommend system-wide efficiency strategies, which they find can halve fuel burn from aviation by 2050. That seems incredible, but they argue that there are efficiencies that individual companies are unable to address, but that can be achieved with system wide policies.

The next point is a bit more obvious – switching to sustainable aviation fuel (SAF). This mostly means making jet fuel from biomass. They mostly recommend policy changes that will help the industry rapidly scale up biofuel production from biomass. That’s really the only way to decarbonize jet travel. Hydrogen will never be energy dense enough for aviation.

We are on the verge of seeing commercial electric planes, mainly because of advances in battery technology. These could fill the regional service and small city routes, with ranges in the 300-400 mile zone (and likely to increase as battery technology continues to advance). Not only would an electric plane industry replace current fossil-fuel burning regional flights, but they could expand the industry and displace other forms of travel. Many more people may choose to take a quick flight from a regional airport than drive for 8 hours.

Their last recommendation is essentially a roll of the dice: “Launching several moonshot technology demonstration programmes designed to rapidly assess the viability and scalability of transformative technologies, bringing forward the timeline for their deployment.”

This sounds partly like an admission that we don’t currently have all the technology we would need to fully decarbonize aviation. Maybe they consider this to be not absolutely necessary but a good option. In any case, I am always in favor of supporting research in needed technology areas. This has generally proven to be an investment worth making.

As is often the case, this all looks good on paper. We just have to actually do it.

The post Decarbonizing Aviation and Agriculture first appeared on NeuroLogica Blog.

High-temperature superconducting cables that could transform the power grid may be increasingly viable, thanks to a side effect of fusion energy research and new ways to cool the wires

Fifteen trivia questions from previous aviation themed episodes of Skeptoid.

A research team has developed a low-cost iron chloride cathode for all-solid-state lithium-ion batteries, which could significantly reduce costs and improve performance for electric vehicles and large-scale energy storage systems.

Noctilucent clouds were once thought to be a fairly modern phenomenon. A team of researcher have recently calculated that Earth and the entire Solar System may well have passed through two dense interstellar clouds causing global noctilucent clouds that may have driven an ice age. The event is thought to have happened 7 million years ago and would have compressed the heliosphere, exposing Earth to the interstellar medium. 

Interstellar clouds are vast regions of gas and dust that flat between the stars inside galaxies. They are mostly made up of hydrogen along with a little helium and trace elements of heavier elements. They are a key part of the life circle of stars providing the materials for new stars to be formed and are seeded with elements after stars die. The clouds vary significantly in size, density and location and are an important part of the evolution of the Galaxy.

An annotated illustration of the interstellar medium. The solar gravity lens marks the point where a conceptual spacecraft in interstellar space could use our sun as a gigantic lens, allowing zoomed-in close-ups of planets orbiting other stars. Credits: Charles Carter/Keck Institute for Space Studies

Earth’s journey around the Galaxy is not for the impatient for it takes about 250 million years to complete one full orbit at a speed of 828,000 kilometres per hour. Currently the Solar System is located in the Orion Arm, one of the spiral arms of our Galaxy. During the journey, Earth travels through different regions, encountering stars and different densities of the interstellar medium. It experiences gravitational interactions with nearby stars and nebula sometimes exerting  subtle interactions. Regardless of the immense journey, the stars of our Galaxy remain relatively unchanged over a human lifetime. 

The Milky Way is a spiral galaxy with several prominent arms containing stellar nurseries swathed in pink clouds of hydrogen gas. The sun is shown near the bottom in the Orion Spur. Credit: NASA

A team of astronomers let by Jess A. Miller from the Department of Astronomy of Boston University have traced the path of the Sun back through time. In doing so, they have identified two occasions when the Earth and Solar System passed through two dense interstellar clouds. One of the crossings occurred 2 million years ago, the other 7 million years ago. Exploring the properties of the clouds, the team assert that the clouds are dense enough that they could compress the solar wind to inside the orbit of Earth. 

The Solar Wind is a constant stream of charged particles, mostly electrons and protons that are emitted from the upper layer of the Sun’s atmosphere, the corona. The particles travel through the Solar System at speeds between 400 and 800 kilometres per second. The edge of our Solar System is defined as the point where the solar wind merges with the interstellar medium.

A composite image comprised of the Sun’s surface, corona, and digitally-added coronal loops rendered by Andrew McCarthy. (Credit: Andrew McCarthy)

Previous teams have analysed climate change events due to these interstellar medium interactions with similar findings. Global cooling has been the result with an ice age being triggered. The study by Miller and team have readdressed this very topic using modern technology and processes. 

The team find that the interactions have indeed played a part in changes to the atmosphere of Earth. They find that levels of hydrogen in the upper atmosphere would have increased substantially. The newly acquired hydrogen would be converted to water molecules in the lower atmosphere and it would also have led to a reduction in mesospheric levels of ozone. These processes would have led to the appearance of global noctilucent clouds in the mesosphere. They would not have been permanent but may have blocked 7% of sunlight from reaching Earth, plunging our planet into an ice age.

Source : Earth’s Mesosphere During Possible Encounters With Massive Interstellar Clouds 2 and 7 Million Years Ago

The post What Happens to the Climate When Earth Passes Through Interstellar Clouds? appeared first on Universe Today.