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Neutron stars are as dense as the nucleus of an atom. They contain a star’s worth of matter in a sphere only a dozen kilometers wide. And they are light-years away. So how can we possibly understand their interior structure? One way would be to simply spin it. Just spin it faster and faster until it reaches a maximum limit. That limit can tell us about how neutron stars hold together and even how they might form. Obviously, we can’t actually spin up a neutron star, but it can happen naturally, which is one of the reasons astronomers are interested in these maximally spinning stars. And recently a team has discovered a new one.

All neutron stars rotate on their axes. They form from the collapse of a massive star’s core, and just as an ice skater spins faster as they pull in their arms, a neutron star spins up as it forms. Young neutron stars can rotate hundreds of times a second, though they generally slow down as they age. Interactions between their magnetic fields and interstellar space cause their rate of rotation to decay. This is why, for example, we can observe pulsars gradually slow down over time.

But many neutron stars have a binary companion. If their companion happens to be a closely orbiting regular star, the neutron star can pull off some of the companion’s outer layer and capture it. The slow exchange of matter can cause the neutron star to speed up as it essentially steals some of the orbital angular momentum of the companion. They are known as millisecond pulsars because they emit a radio pulse every few milliseconds. They are the fastest-rotating stars in the cosmos.

So, just how fast can these neutron stars spin? The record for the fastest spinning pulsar is held by PSR J1748–2446ad. Observations in 2004 and 2005 confirmed it rotates 716 times per second. That’s a bit faster than number two, which rotates at 707 times a second. This new study has found another neutron star rotating at 716 times a second, and it’s interesting because it isn’t a pulsar.

X-ray burst showing the 716 Hz oscillation. Credit: Jaisawal, et al

Known as 4U 1820-30, it is part of a binary X-ray system. As the neutron star captures material from its companion, part of its surface will heat up to such a degree that it emits X-rays. As the neutron star rotates, the hot-spot swings in and out of view, and we observe a periodic pulsation of X-rays. Using NASA’s NICER X-ray telescope, the team observed the binary from 2017 to 2021 and captured data on 15 powerful X-ray bursts. One of these bursts had a clear periodicity of 716 Hz. This strongly suggests the neutron star rotates at that rate.

While it could just be a statistical fluke, the fact that we now have two 716 Hz neutron stars found in two different ways suggests they may be near the maximal rotation limit for a neutron star.

Reference: Jaisawal, Gaurava K., et al. “A Comprehensive Study of Thermonuclear X-Ray Bursts from 4U 1820–30 with NICER: Accretion Disk Interactions and a Candidate Burst Oscillation.” The Astrophysical Journal 975.1 (2024): 67.

The post Astronomers Have Found the Fastest Spinning Neutron Star appeared first on Universe Today.

The health benefits of fermented food and drink have long been touted, but firm evidence in favour of kombucha, sauerkraut and kefir is surprisingly elusive

Yesterday we took a drive to Utah’s Bryce Canyon National Park, a 2.5-hour trip from where I’m staying in Ivins, Utah.  Bryce is located where the red pin is in this Wikipedia map:

SANtosito, CC BY-SA 4.0, via Wikimedia Commons

It turns out that Bryce is one of the most beautiful places I’ve seen in America—indeed, anywhere on Earth. To me, its splendor, exemplified by the “amphitheaters” that contain the red geological spires known as hoodos, is unparalleled. I’ll show some photos below. First, a few words from Wikipedia:

The major feature of the park is Bryce Canyon, which despite its name, is not a canyon, but a collection of giant natural amphitheaters along the eastern side of the Paunsaugunt Plateau. Bryce is distinctive due to geological structures called hoodoos, formed by frost weathering and stream erosion of the river and lake bed sedimentary rock. The red, orange, and white colors of the rocks provide spectacular views for park visitors. Bryce Canyon National Park is much smaller and sits at a much higher elevation than nearby Zion National Park. The rim at Bryce varies from 8,000 to 9,000 feet (2,400 to 2,700 m).

And the geology, which explains these bizarre formations:

The Bryce Canyon area experienced soil deposition that spans from the last part of the Cretaceous period and the first half of the Cenozoic era. The ancient depositional environment varied. Dakota Sandstone and Tropic Shale were deposited in the warm, shallow waters of the advancing and retreating Cretaceous Seaway (outcrops of these rocks are found just outside park borders).

The Laramide orogeny affected the entire western part of what would become North America starting about 70 million to 50 MYA. This event helped to build the Rocky Mountains and in the process closed the Cretaceous Seaway. The Straight Cliffs, Wahweap, and Kaiparowits formations were victims of this uplift. The Colorado Plateaus rose 16 MYA and were segmented into plateaus, separated by faults and each having its own uplift rate.

This uplift created vertical joints, which over time preferentially eroded. The soft Pink Cliffs of the Claron Formation eroded to form freestanding hoodoo pinnacles in badlands, while the more resistant White Cliffs formed monoliths The brown, pink, and red colors are from hematite (iron oxide; Fe2O3); the yellows from limonite (FeO(OH)·nH2O); and the purples are from pyrolusite (MnO2).

So we have a sedimentary sandstone formation that of course formed the seabed, and, under the pressure of colliding tectonic plates (I’m dong the best I can here), produced a huge uplift of the seabed, with Bryce being part of a huge sandstone cliff.  Thrust above the ground, the cliff was subject to erosion as well as weathering as frost and ice invaded the cracks in the soil. That erosion of softer bits, as well as the cracking, created structures like these. These are “mini-hoodoos” that you see before you enter the Park itself:

The area is called “Dixie” because there was a period during which settlers tried to grow cotton in the area. This endeavor ultimately failed, probably because of extreme dryness and lack of water. They haven’t yet purged the name “Dixie” from many institutions and parks, but that will happen. There is even a “Dixie Technical College.”

These are just small previews of the Big Show that is Bryce Canyon:

Entering the park, you’re warned to stay away from prairie dogs (cute rodents in the genus Cynomys) who build extensive underground tunnel systems. Their fleas carry the bacterium the causes bubonic plague, which persists at a low level in the U.S (about nine cases a year in the past couple decades). Now that we have antibiotics, getting plague is no longer the death sentence it was in the Middle Ages.

The glories of the park are the series of hoodoo-containing ampitheaters, which you can see from above by climbing up a short path. They are breathtaking:

These spires are huge, not just small excrescences:

A panorama: be sure to click to enlarge the photo:

The day was bloody cold, with snow on the ground during much of the two-hour drive and some near white-outs. But the weather cleared sufficiently when we got to the Park so that photography was good, in muted light. Here’s my friend Phil Ward standing on the edge of the cliff, trying not to slip and fall into the canyon.

. . . and Professor Ceiling Cat in the same place: a vanity photo

More of the Canyon. It is much smaller than Zion but more breathtaking. You can pretty much take in the whole thing by climbing to one of the lookout points (this one was about 8,000 feet high, so you get out of breath hiking up):

Another panorama: click to enlarge:

After we froze our ears, hands, and noses (there was a stiff wind up there, and the temperature was below freezing), we parked the car overlooking some scenery and had a healthy Phil Ward-ian lunch (turkey breast and cream cheese on walnut bread, along with a ginger drink, a banana, and an apple). Then we repaired to the visitor center, which had good explanations and diagrams of how the park was formed. There were also relics from the Native Americans who lived in this area as well as the Mormon settlers. Here is a water jug from the late 1800s made of resin-coated wood:

There were lots of Bryce-related geegaws for sale in the gift ship, and I had a bit of fun with two pack rat puppets (rodents of the genus Neotoma).

Then it was time for the long drive home, and once again we had to go through snow and rain. But we were fortunate that the weather in the Park was good when we were there, and we could truly say this:

And when we got home, one of the people who co-owns the beautiful house where I’m staying served us raw oysters, grilled oysters, grilled burgers, and then two beautiful grilled ribeye steaks:

And the sun will come out tomorrow (in fact, today). The view from the house where I’m staying:

If you’re in southern Utah, you must visit both Bryce Canyon and Zion National Parks. But if you can visit only one, it must be Bryce. Truly, I’ve traveled a lot of this planet, and seen some beautiful places, but Bryce is surely among the top ten. (Others include Mt. Everest from Kala Pattar, Machu Picchu, the Taj Mahal under a full moon, and almost any part of Antarctica, as well as the giant sequoias of California.)

Feel free to list below the most beautiful places you’ve seen! This might help me amend my bucket list.

Diets that claim to control excess oestrogen or stress hormones are all the rage on Instagram and TikTok. They could be good for us, just not for the reasons claimed

On my recent trip to CERN, the lab that hosts the Large Hadron Collider, I had the opportunity to stop by the CERN control centre [CCC]. There the various particle accelerator operations are managed by accelerator experts, who make use of a host of consoles showing all sorts of data. I’d not been to the CCC in person — theoretical physicists congregate a few kilometers away on another part of CERN’s campus — although back in the LHC’s very early days, when things ran less smoothly, I used to watch some of the CCC’s monitoring screens to see how the accelerator was performing.

The atmosphere in the control room was relatively quiet, as the proton-proton collisions for the year 2024 had just come to an end the previous day. Unlike 2023, this has been a very good year. There’s a screen devoted to counting the number of collisions during the year, and things went so well in 2024 it had to be extended, for the first time, by a “1” printed on paper.

The indication “123/fb” means “123-collisions-per-femtobarn”, while one-collision-per-femtobarn corresponds to about 1014 = 100,000,000,000,000 proton-proton collisions. In other words, the year saw more than 12 million billion proton-proton collisions at each of the two large-scale experiments, ATLAS and CMS. That’s about double the best previous year, 2018.

Yes, that’s a line of bottles that you can see on the back wall in the first photo. Major events in the accelerator are often celebrated with champagne, and one of the bottles from each event is saved for posterity. Here’s one from a few weeks ago that marked the achievement of 100-collisions-per-femtobarn.

With another one and a half seasons to go in Run 3 of the LHC, running at 13.6 TeV of energy per collision (higher than the 13 TeV per collision in Run 2 from 2015 to 2018, and the 7 and 8 TeV per collision in Run 1 from 2010 to 2012), the LHC accelerator folks continue to push the envelope. Much more lies ahead in 2029 with Run 4, when the collision rate will increase by another big step.

Meanwhile, in Dobrzyn, Hili has come to a conclusion:

Hili: Reality is unworkable. A: That’s why so few are treating it seriously.

Hili: Rzeczywistość nie nadaje się do użytku.
Ja: Dlatego niewielu traktuje ją poważnie.

Carbon is the building block for all life on Earth and accounts for approximately 45–50% of all dry biomass. When bonded with elements like hydrogen, it produces the organic molecules known as hydrocarbons. When bonded with hydrogen, oxygen, nitrogen, and phosphorus, it produces pyrimidines and purines, the very basis for DNA. The carbon cycle, where carbon atoms continually travel from the atmosphere to the Earth and back again, is also integral to maintaining life on Earth over time.

As a result, scientists believe that carbon should be easy to find in space, but this is not always the case. While it has been observed in many places, astronomers have not found it in the volumes they would expect to. However, a new study by an international team of researchers from the Massachusetts Institute of Technology (MIT) and the Harvard-Smithsonian Center for Astrophysics (CfA) has revealed a new type of complex molecule in interstellar space. Known as 1-cyanoprene, this discovery could reveal where the building blocks of life can be found and how they evolve.

The research was led by Gabi Wenzel, a postdoctoral researcher from the Department of Chemistry at MIT. She was joined by researchers from the CfA, the University of British Columbia, the University of Michigan, the University of Worchester, the University of Virginia, the Virginia Military Institute (VMI), the National Science Foundation (NSF), the National Radio Astronomy Observatory (NRAO), and the Astrochemistry Laboratory at NASA’s Goddard Space Flight Center (GSFC). The paper that describes their findings recently appeared in the journal Science.

Artist’s impression of complex organic molecules in space. Credit: NSF/NSF NRAO/AUI/S. Dagnello

For their study, the team relied on the NSF Green Bank Telescope (GBT), the most accurate, versatile, and largest fully-steerable radio telescope in the world, located at the Green Bank Observatory in West Virginia. This sophisticated instrument allowed the team to detect the presence of 1-cyanopyrene based on its unique rotational spectrum. 1-cyanoprene is a complex molecule composed of multiple fused benzene rings and belongs to the polycyclic aromatic hydrocarbon (PAHs) class of molecules. On Earth, they are created by burning fossil fuels or other organic materials, like charred meat or burnt bread.

By studying PHAs, astronomers hope to learn more about their lifecycles and how they interact with the ISM and nearby celestial bodies. As co-author Harshal Gupta, the NSF Program Director for the GBO and a Research Associate at the CfA, explained in a recent CfA press release:

“Identifying the unique rotational spectrum of 1-cyanopyrene required the work of an interdisciplinary scientific team. This discovery is a great illustration of synthetic chemists, spectroscopists, astronomers, and modelers working closely and harmoniously.”

This was an impressive feat due to the difficulty (or even impossibility) of detecting these molecules due to their large size and lack of a permanent dipole moment. “These are the largest molecules we’ve found in TMC-1 to date. This discovery pushes the boundaries of our understanding of the complexity of molecules that can exist in interstellar space,” added co-author MIT professor Brett McGuire, who is also an adjunct astronomer at the NSF and the NRAO.

Previously, these molecules were believed to form only in high-temperature environments, like the region surrounding older stars. This concurs with what astronomers have known for a long time about certain carbon-rich stars, which produce massive amounts of small molecular sheets of carbon that they then distribute into the interstellar medium (ISM). In addition, previous research has suggested that the infrared fluorescence of PAHs – caused by the absorption of ultraviolet radiation from nearby stars – could be responsible for infrared bands observed in many celestial objects.

Artist’s impression of Green Bank Telescope conducting radio astronomy with the help of AI algorithms. Credit: Breakthrough Listen/Danielle Futselaar.

The intensity of these bands has led some astronomers to theorize that PAHs could account for a significant fraction of carbon in the ISM. Other astronomers have maintained that these carbon-rich molecules could not survive the harsh conditions of interstellar space because temperates in the ISM are far too low – averaging about 10 K (-263 °C; -442 °F). However, the 1-cyanopyrene molecules Wenzel and her colleagues observed were located in the nearest star-forming region to Earth, the cold interstellar cloud known as Taurus Molecular Cloud-1 (TMC-1).

Since this Nebula has not yet started forming stars, its temperature is the same as that of the ISM. “TMC-1 is a natural laboratory for studying these molecules that go on to form the building blocks of stars and planets,” said Wenzel. These observations suggest that PHAs like 1-cyanopyrene may have a different formation mechanism entirely and/or can survive the harsh environment of space. In the meantime, detecting cyanopyrene can provide indirect evidence of even larger and more complex molecules in future observations. 

This research was supported by measurements and analysis conducted by the molecular spectroscopy laboratory of Dr. Michael McCarthy at the CfA. As he indicated:

“The microwave spectrometers developed at the CfA are unique, world-class instruments specifically designed to measure the precise radio fingerprints of complex molecules like 1-cyanopyrene. Predictions from even the most advanced quantum chemical theories are still thousands of times less accurate than what is needed to identify these molecules in space with radio telescopes, so experiments in laboratories like ours are indispensable to these ground-breaking astronomical discoveries.”

Further Reading: CfA

The post Astronomers Discover Potential New Building Block of Organic Matter in Interstellar Space appeared first on Universe Today.

The Solar System’s hundreds of moons are like puzzle pieces. Together, they make a picture of all the forces that can create and modify them and the forces that shape our Solar System. One of them is Miranda, one of 28 known moons that orbit the ice giant Uranus. Miranda is its smallest major moon, at 471 km in diameter.

New research shows that this relatively small, distant moon may be hiding something: a subsurface ocean.

Miranda stands out from the other moons for one reason: its surface is a bizarre patchwork of jumbled terrain. There are cratered areas, rough scarps, and grooved regions. It may have the tallest cliff in the Solar System, a 20 km drop named Verona Rupes. Many researchers think its surface is deformed by tidal heating from gravitational interactions with some of the Uranus’ other moons.

New research in The Planetary Journal set out to explain Miranda’s jumbled geology. It’s titled “Constraining Ocean and Ice Shell Thickness on Miranda from Surface Geological Structures and Stress Modeling.” The lead author is Caleb Strom, a graduate student at the University of North Dakota.

“To find evidence of an ocean inside a small object like Miranda is incredibly surprising,”

Tom Nordheim, co-author and planetary scientist at the Johns Hopkins Applied Physics Laboratory

Scientists don’t have much to go on when it comes to Miranda. The only spacecraft to image it was Voyager 2 in 1986. Even then, the flyby was brief, and the spacecraft only imaged the moon’s southern hemisphere. But that was enough to reveal the moon’s bizarre and complex geological surface features. Miranda’s strange surface coronae attracted a lot of attention.

This figure from the study shows some of Miranda’s surface features. The moon is known for its coronae features, two of which are labelled here. Image Credit: Strom et al. 2024.

When the images were first received, scientists were baffled by Miranda’s complexity. Some called it a “patchwork planet,” and there was much healthy speculation about what created it. Attempts to understand the moon are still limited by the amount of data that Voyager 2 provided. However, modern scientists have access to a more powerful tool than scientists did in the 80s: computer models and simulations.

Strom and his co-researchers used a computer model to work backward from Miranda’s current surface. They started by mapping Miranda’s surface features, including its cracks, ridges, and unique trapezoidal coronae, and then reverse-engineered it. They tested different models of the moon’s interior to see what could account for the varied surface.

This simple schematic shows the four-layer model Strom and his co-researchers worked with. Image Credit: Strom et al. 2024.

The model that best matched the surface was one where Miranda had a vast ocean under its surface some 100-500 million years ago. The icy crust is probably 30 km thick or less, and the ocean could be up to 100 km thick.

“Our results show that a thin crust (?30 km) is most likely to result in sufficient stress magnitude to cause brittle failure of ice on Miranda’s surface,” the authors explain in their research. “Our results also suggest the plausible existence of a ?100 km thick ocean on Miranda within the last 100–500 million yr.”

“To find evidence of an ocean inside a small object like Miranda is incredibly surprising,” said Tom Nordheim, a planetary scientist at the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, a study co-author, and the principal investigator on the project that funded the study. “It helps build on the story that some of these moons at Uranus may be really interesting — that there may be several ocean worlds around one of the most distant planets in our solar system, which is both exciting and bizarre.”

Tidal heating is responsible for this, and it came from gravitational relationships between Miranda and Uranus’ other moons. Moons tug on each other, and when they’re in an orbital resonance with one another, where each moon’s period around a planet is an exact integer of the others’ periods, those tugs are amplified. These forces can periodically deform the moons, and as they’re squeezed, they heat up, keeping subsurface oceans warm and liquid.

Miranda and other moons of Uranus were likely in resonance in the past, which could’ve created surface fractures and related terrain.

A digital elevation model (DEM) of Miranda’s Inverness Coronae. The relative elevation ranges from 0 km (purple) to 4 km (red). Image Credit: Beddingfield et al. 2022.

However, resonances don’t last forever, and the researchers think that some time ago, Miranda left orbital resonance, and its interior began to cool. They don’t think it’s completely cooled yet because if the ocean had completely frozen, it would’ve expanded and displayed telltale surface cracks. So, the interior ocean likely still exists but is probably much thinner than in the past. “But the suggestion of an ocean inside one of the most distant moons in the solar system is remarkable,” Strom said.

Nobody predicted that Miranda would have an ocean. As far as scientists could tell, it was a frozen ball. But they’ve been wrong about moons before.

Researchers used to think that Saturn’s moon, Enceladus, the most reflective object in the Solar System, was just a ball of ice. After all, its surface is smooth and clearly frozen solid. However, the Cassini mission showed us that it may not be totally frozen. There’s a bevy of evidence that Enceladus has a warm ocean under a layer of ice.

This false-colour image of the plumes erupting from Enceladus is easily recognizable to many. Enceladus and Miranda are similar in important ways. Could Miranda also be geologically active? Image Credit: NASA/ESA

“Few scientists expected Enceladus to be geologically active,” said co-author Alex Patthoff. “However, it’s shooting water vapour and ice out of its southern hemisphere as we speak.”

Since both Enceladus and Miranda are roughly the same size and may have similar ice shells, it increases the chances that Miranda also has an ocean. Other moons, like Saturn’s Europa, may also be icy ocean moons. Now, scientists think these moons and their warm oceans are the best targets in the search for life in our Solar System.

Other recent research suggests that Miranda could be more like Enceladus than thought. One 2023 study showed that the moon may be releasing material into space like Enceladus does. The ESA and NASA are both sending probes to Jupiter to study Europa and other potential ocean moons. Should we expand that search to distant Uranus and its small moon Miranda?

An artist’s impression of Uranus and its five largest moons (innermost to outermost): Miranda, Ariel, Umbriel, Titania and Oberon. A 2023 paper showed that Ariel and/or Miranda could be releasing material into space. Image Credit: NASA/Johns Hopkins APL/Mike Yakovlev

“We won’t know for sure that it even has an ocean until we go back and collect more data,” said study co-author Nordheim. “We’re squeezing the last bit of science we can from Voyager 2’s images. For now, we’re excited by the possibilities and eager to return to study Uranus and its potential ocean moons in depth.”

For now, all we have is decades-old Voyager 2 data. However, the data and the computer models the team employed shed new light on Miranda.

“We interpret the tidal stress model results to indicate that at some point in Miranda’s geologic past, it experienced an intense heating event that resulted in a thin crust (?30 km). Such a thin crust would also have resulted in a ?100 km thick ocean to account for the molten part of the hydrosphere. This thin ice crust and thick ocean could have allowed for intense tidal stress leading to significant geologic deformation in the form of brittle deformation at Miranda’s surface,” the authors explain.

“In conclusion, our results suggest that Miranda could have had a subsurface ocean in the geologically recent past from an intense heat pulse, consistent with dynamical modelling results of previous studies,” they conclude.

The post There’s Another Ocean Moon Candidate: Uranus’ Tiny Moon Miranda appeared first on Universe Today.

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The United States as Global Liberal Hegemon: How the U.S. Came to Lead the World examines America’s role as the global liberal hegemon. Using a historical analysis to understand how the United States came to serve as the world leader, Goldberg argues why the role of a liberal hegemon is needed, whether the United States has the ability to fulfill this role, and what the pitfalls and liabilities of continuing in this role are for the nation. He also considers the impact that this role on the global stage has for the country as well as individual citizens of the United States. Goldberg argues that the United States’s geographic location away from strong competitors, it’s role as the dominant economy for much of the 20th century, and its political culture of meritocracy all contributed to the United States taking this role in the 1940s. He also argues that the role of liberal hegemon has shifted to include not only being the international policeperson but also to be the world’s central banker, a role that at this time only the United States can fill.

Edward Goldberg is a leading expert in the area of where global politics and economics intercept. He teaches International Political Economy at the New York University Center for Global Affairs where he is an Adjunct Assistant Professor. He is also a Scholarly Practitioner at the Zicklin Graduate School of Business of Baruch College of the City University of New York where he teaches courses on globalization. With over 30 years of experience in international business and as a former member of President Barack Obama’s election Foreign Policy Network Team, Dr. Goldberg is the author of Why Globalization Works For America: How Nationalist Trade Policies Destroy Countries, and The Joint Ventured Nation: Why America Needs A New Foreign Policy. He is a much-quoted essayist and public speaker on the subjects of Globalization, European-American relations, U.S.-Russian and China relations. He has commented on these issues on PBS, NPR, CBS, Bloomberg, and in The New York Times, The Hill, and the Huffington Post. His new book is The United States as Global Liberal Hegemon: How the U.S. Came to Lead the World.

Shermer and Goldberg discuss:

“In the 1940s, when America anointed itself hegemon, somewhat like in Great Britain in the nineteenth century, American foreign policy was largely, aside from Harry Truman and a few others, dominated by a group of men who generally all went to similar prep schools and graduated from Princeton, Yale, or Harvard. This has changed drastically. If there is one common domestic thread in American post-World War II history, it is how American society and political life has become noticeably more diverse.”

• The 2024 presidential election is the first time Americans are voting on whether the U.S. should remain the so-called “leader of the free world” – or just go it alone as Donald Trump suggests. Even in the late 1930s, the heyday of isolationism, isolationism never appeared on the ballot. In fact in the presidential election of 1940, the Republican candidate Wendel Wilkie was an internationalist.
• What are the benefits to American citizens to continue in this role? What are the costs? And why can’t another nation or some institution play this role?
• Does the U.S. need allies to be successful or are relationships/institutions like NATO “obsolete” as Trump has stated?
• Why does there need to be a global leader or as Secretary of State Blinken said, an organizer? Is there any logic for instance to Donald Trump’s statement that he would “encourage Russia to do whatever the hell they want?”
• As the world faces new globalized communal problems, climate change, pandemics, financial contagion, etc., is the U.S. political culture capable of leading the world against these more abstract threats?
• Secretary of State Blinken’s statement, “Whether we like it or not, the world does not organize itself,” I look at why the United States is the only country capable of organizing the world, of being the liberal hegemon.
• the world’s central banker, the financial fireman of the world, a position at this time only the United States can fulfill.
• why a liberal hegemon is needed. Why can’t the United Nations organize the world or be the cop?
• The United States was the only major nation whose birth was influenced by the philosophical enlightenment movement. Thus, it has a very different view of the role of government. In America, the government was created not to watch over the individual welfare of its citizens but to guarantee their fundamental rights and liberties. That perspective emphasizes the individual over the community. Does America’s political culture, based on an aggrandized view of the eighteenth-century enlightenment theory of individual rights, hinder its ability to lead in the twenty-first century?
• Foreign governments have been trying to influence American foreign policy since the time of George Washington.
• disastrous mistakes like Vietnam and Iraq
• The March of Folly
• are the rewards of hegemony worth the price for the American citizen? $1.120 trillion the United States spent on defense in 2022. This expenditure created approximately 800,000 civilian jobs and 1.3 million active-duty jobs. But could these funds have created larger economic growth if applied to other areas?
• U.S. has defense treaties with 51 countries plus independent security understandings with others.
• Is the Iowa farmer aware that the reason their soybeans can be shipped safely around the world is because of the protection of the United States Navy?
• Roosevelt State of the Union address to Congress January 6, 1941: “No realistic American can expect from a dictator’s peace international generosity, or return of true independence, or world disarmament, or freedom of expression, or freedom of religion-or even good business … Such a peace would bring no security for us or for our neighbors. Those, who would give up essential liberty to purchase a little temporary safety, deserve neither liberty nor safety.”
• The United States has agreed to treaties obligating it to the defense of 51 countries:
  • 28 countries in NATO, which is essentially a defense umbrella for Canada and most of Europe
  • 18 through the Rio Treaty that applies to most of Central and South America
  • ANZUS Treaty with Australia and New Zealand
  • A bilateral treaty with Japan
  • A bilateral treaty with South Korea
  • A bilateral treaty with the Philippines.
• The theory behind most of these treaties derived from the lessons of World War I and II and especially the isolationist period between those two wars. Essentially, the underlying idea for these agreements is to halt aggression early rather than letting it metastasize and potentially overcome the United States.

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Researchers have developed an electrochemical reactor that has the potential to drastically reduce energy consumption and cost for direct air capture.

Simulations suggest that when a quantum battery shares a quantum state with the device it is powering, the device can gain more charge than was stored in the battery to begin with

Simulations suggest that when a quantum battery shares a quantum state with the device it is powering, the device can gain more charge than was stored in the battery to begin with

In some recent years, the Amazon biome released more carbon than it absorbed, and further degradation could make it a permanent shift

Saturn’s moon, Titan, is an anomaly among moons. No other moons have surface liquids, and aside from Earth, it’s the only other Solar System object with liquids on its surface. However, since Titan is so cold, the liquids are hydrocarbons, not water. Titan’s water is all frozen into a surface layer of ice.

New research suggests that under the surface, Titan is hiding another anomaly: a thick crust of methane.

The evidence for the methane comes mostly from craters. Observations have found few confirmed impact craters on the frigid moon, and the ones that have been observed are hundreds of meters shallower than the same-sized craters on other moons. If Titan’s crust was rock, the craters should be much deeper.

The new research, published in The Planetary Science Journal, is titled “Rapid Impact Crater Relaxation Caused by an Insulating Methane Clathrate Crust on Titan.” Lauren Schurmeier, from the Hawai’i Institute of Geophysics and Planetology at the University of Hawai’i at Manoa, is the lead author.

Titan stands apart from other moons for multiple reasons. Unlike any other natural satellites in the Solar System, it has a thick atmosphere. Its atmosphere is about 50% more dense than Earth’s and extends about 600 km into space. A haze made of complex organic molecules called tholins gives the atmosphere its characteristic orange colour. The atmosphere is so thick that it blocks optical light, making Titan’s surface features nearly inscrutable.

The Cassini spacecraft has given us our best looks at Titan. It used radar and infrared instruments to see the moon’s surface. The small Huygens probe that went to Saturn with Cassini was released into Titan in 2005 to study the atmosphere and surface. It’s thanks to Huygens that we have our best images of Titan’s surface.

The new research suggests a link between Titan’s unusual atmosphere, its shallow surface craters, and a layer of methane in the moon’s crust. The methane keeps the underlying layer of ice convective by insulating it and helps impact craters rebound quickly and remain shallow.

There’s no consensus on how many craters Titan has because its surface is veiled behind its thick atmosphere, but there is some data on the craters.

This graph shows crater candidate counts binned by latitude regions and certainty level. Craters of certainty level 1 have more lines of evidence pointing toward an impact crater origin; certainty level 4 is the least certain. Image Credit: Schurmeier et al. 2024.

The research centres on the fact that Titan displays few craters and that the ones we do see are shallow. This sets it apart from other moons.

These are Cassini SAR (synthetic aperture radar) images of Titan’s impact craters. Arrows indicate potential forms of crater modification processes, including dunes and sands (purple), channels (blue), and significant crater rim erosion (pink). Afekan crater is one of Titan’s largest impact craters at 115 km. Jupiter’s moon, Ganymede, which is about the same size as Titan, has way more craters, including 20 that are larger than Afekan. Image Credit: NASA/ Cassini

“This was very surprising because, based on other moons, we expect to see many more impact craters on the surface and craters that are much deeper than what we observe on Titan,” said lead author Schurmeier. “We realized something unique to Titan must be making them become shallower and disappear relatively quickly.”

A handful of processes have been proposed to explain Titan’s diminishing craters. Liquid hydrocarbon rainfall, aeolian sand infill, and topographic relaxation induced by insulating sand infill have all been discussed. “Here, we propose an additional mechanism: topographic relaxation due to an insulating methane clathrate crustal layer in Titan’s upper ice shell,” the authors write.

This simple schematic of Titan’s interior (not to scale) shows a methane clathrate crust over a convecting ice shell. The methane clathrate can insulate the ice below and keep it convective. That convection could explain why Titan’s craters are so few and so shallow. Image Credit: Schurmeier et al. 2024.
 

There’s very little new information coming from Titan, so researchers have to work with what they have. To try to understand its shallow craters, the researchers built a computer model. They used it to try to understand how Titan’s topography might respond to impacts if a layer of methane clathrate was trapped under the surface. A clathrate is a substance where one type of molecule is trapped within a structure of molecules of another type. In this case, methane is trapped in water ice.

Methane’s insulating properties are key.

“Methane clathrate is stronger and more insulating than regular water ice,” said Schurmeier. “A clathrate crust insulates Titan’s interior, makes the water ice shell very warm and ductile, and implies that Titan’s ice shell is or was slowly connecting.”

With their model, they tested clathrate crusts that were 5, 10, 15, or 20 km thick. They used craters that were 40, 85, 100, and 120 km in diameter, each with two initial depths based on Ganymede’s crater diameters and depths. The result?

“We find that all clathrate crustal thicknesses result in rapid topographic relaxation despite Titan’s cold surface temperature,” the researchers write. “The 5 km thick clathrate crust can reproduce nearly all of the observed shallow depths, many in under 1000 yrs.”

They also found that a 10 km clathrate crust can reproduce Titan’s observed crater depths over geologic timescales. “If relaxation is the primary cause of the shallow craters, then the clathrate thickness is likely 5–10 km thick,” they write.

Across all simulations, most of the crater relaxation occurred in 1,000 years. “This finding suggests that thin clathrate crusts cause crater shallowing in a geological instant, similar to a fast-flowing terrestrial glacier,” the authors explain. It could certainly explain why none of Titan’s craters are deep.

The researchers point out a couple of caveats, though. They assumed that Titan’s initial craters had depths similar to Ganymede’s. They could’ve formed at different depths and shapes. Their model also didn’t include heat generated by the impact itself or account for an impact-triggered discontinuity in the methane clathrate layer. “These thermal and dynamic changes might alter the morphological evolution of the crater,” they write.

Juno captured this image of Ganymede in July 2022. The moon’s impact craters are easily visible, including the crater Tros, which is prominent below the center at left. Image Credit: NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill

This research adds to Titan’s mystery and our fascination with the unusual moon. It also adds another element to comparisons with Earth. Earth and Titan both have surface liquid and are the only two objects in the Solar System that do. Earth also has methane clathrates in its polar regions.

“Titan is a natural laboratory to study how the greenhouse gas methane warms and cycles through the atmosphere,” said Schurmeier. “Earth’s methane clathrate hydrates, found in the permafrost of Siberia and below the arctic seafloor, are currently destabilizing and releasing methane. So, lessons from Titan can provide important insights into processes happening on Earth.”

In the end, their results are clear: “We conclude that if crater relaxation is the primary cause of Titan’s unexpectedly shallow craters, then the clathrate crust is 5–10 km thick,” the authors write.

The post Titan May Have a Methane Crust 10 Km Thick appeared first on Universe Today.

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