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The ESA’s Mars Express orbiter captured an image of the remains of a vast ancient lake on Mars. The remnant lake bed has been weathered and altered by the passing of billions of years. In the planet’s distant past, scientists say, it held enough water to fill Earth’s Caspian Sea almost three times over.

The leading image shows a region on Mars called Caralis Chaos.

At first glance, it just looks like a vague outline of a depression scrambled and scarred by time, with Mars’ ubiquitous impact craters sprinkled throughout the image. But for scientists who study planetary surface features, the image is rife with clues—clues that connect it to Mars’ warm and watery ancient past and to the ensuing episodes of change the planet underwent.

The following topographical map brings clarity.

Red is high elevation, and blue is low elevation. The lakebed boundaries curve up and away from the bottom centre of the frame towards the top right, skirting around the large central crater. This is one of several lakebeds in the region that were once joined into one vast lake named Lake Eridania. Image Credit: ESA/DLR/FU Berlin. Licence: CC BY-SA 3.0 IGO or ESA Standard Licence

The ancient lakebed consists of several basins surrounding and including the Caralis Chaos region. In the distant past, they were all joined into one big lake named Lake Eridania. It had a surface area of about 1.1 million square km. The largest non-ocean body of water on Earth is the Caspian Sea, with a surface area of 389,000 km.

This image puts the Caralis Chaos region into context. It’s from a 2015 paper that focused on two parts of the Eridania Lake system: Atlantis Chaos and Simois Colles. Image Credit: Adeli et al. 2015.

Liquid water was likely abundant on early Mars between about 4.1 and 3 billion years ago during the Noachian and Hesperian Periods. Mars may have even hosted a massive ocean that covered about one-third of its surface. Eridania Lake was likely a single lake until the late Noachian when Mars gradually lost its water. During that period, the lake was fragmented into multiple smaller lakes.

The ancient lakebed is now punctuated with mounds. Scientists think Mars’ dusty winds initially formed the mounds. Later, they were covered by water, then the water disappeared, and they were exposed to the wind again.

This perspective view shows the mounds on the floor of ancient Lake Eridani. Image Credit: ESA/DLR/FU CC BY-SA 3.0 IGO

The floors of all of the basins that comprised Eridania Lake are covered by light-toned materials containing Fe/Mg-phyllosilicates. The region also has chloride, indicating that a playa region once existed here as the water receded. Some of the geological evidence in the region suggests that some surface water may have survived until long after the Noachian.

This diagram shows how volcanic activity may have caused the deposition of minerals on the floor of Lake Eridania. Chlorides were deposited along the shoreline by evaporation. Image Credit: By Jim Secosky chose this image NASA – https://www.jpl.nasa.gov/spaceimages/details.php?id=PIA22060, Public Domain, https://commons.wikimedia.org/w/index.php?curid=63303061

There’s also evidence of volcanic activity. Two large faults called fossae run through the region. Collectively, they’re known as Sirenum Fossae.

This image shows the extent and depth of ancient Lake Eridania. It also shows Sirenum Fossae, two large faults in the Martian surface. Image Credit: By Jim Secosky modified NASA image – https://photojournal.jpl.nasa.gov/figures/PIA22059_fig1.jpg, Public Domain, https://commons.wikimedia.org/w/index.php?curid=63330708

The region between the two faults is called a graben, a depressed portion of the crust. Sirenum Fossae was formed as Mars’ Tharsis region, a vast volcanic plateau that’s home to Olympus Mons and Tharsis Montes, rose up and put enormous pressure on the crust.

This is a perspective view of one of the Sirenum Fossae fault lines. Image Credit: ESA/DLR/FU CC BY-SA 3.0 IGO

These images all come from the ESA’s Mars Express Orbiter. It has been orbiting Mars since 2004, mapping its surface and minerals and studying the planet’s interior, subsurface, and atmosphere. It has been in orbit for more than 20 years. The ESA has extended its mission until at least the end of 2026 and has given it a provisional extension until 2028.

The post An Ancient Martian Lake Was Larger Than Any Lake on Earth appeared first on Universe Today.

Interview with Forrest Valkai; News Items: Mark Edward, Moon Deep Storage, Pursuit of Happiness, Measuring Blood Pressure, First Complex Life on Earth, Life on Venus Update; Who's That Noisy; Your Questions and E-mails: AC vs DC; Science or Fiction

https://traffic.libsyn.com/secure/sciencesalon/mss455_Andrew_Chow_2024_08_10.mp3 Download MP3

As cryptocurrency rose in popularity during the pandemic, new converts bought into the idea that crypto would not only make them rich, but would usher in imminent revolutions across art, finance, politics, and gaming. Cryptocurrency caught the zeitgeist through figures like FTX CEO Sam Bankman-Fried, who only two years later would be convicted of one of the most calamitous acts of financial fraud in U.S. history.

During his meteoric rise, Sam Bankman-Fried outflanked idealists in the movement like Vitalik Buterin, who sought to build fairer, more democratic systems through Ethereum. Bankman-Fried pursued a growth-obsessed, by-any-means approach to crypto, which proved seductive to those who just wanted to get rich. But this Silicon Valley-like approach also drove the creation of a spate of high-risk financial instruments that mirrored those of the 2008 financial crisis. Accused of misleading investors and mishandling funds, Bankman-Fried became a target of prosecutors.

Now, Cryptomania unfolds the tumultuous twenty months inside this male-dominated, overhyped industry that led to its downfall. Drawing on exclusive reporting and an extensive network in the global NFT community, Andrew Chow chronicles the battle for crypto’s soul, and the human toll of its economic meltdown—from the conmen and eccentrics driving the bubble to the victims caught in its burst.

Andrew R. Chow is a correspondent for Time who covers technology, culture, and business. He has written four Time cover stories, including about the impacts of the AI corporate arms race and a prescient profile of Vitalik Buterin months before the 2022 crypto crash. He has previously written for The New York Times, Pitchfork, and NBC News. His first book is Cryptomania: Hype, Hope and the Fall of a Billion-Dollar Fintech Empire.

Shermer and Chow discuss:

• What is money?
• Fiat money without a gold standard
• Cash, coins, and credit cards
• Bitcoin and crypto currencies as the next step in financial transactions
• Crypto’s utopian philosophies
• What triggered crypto’s pandemic-era bull run.
• How the popularity of Non-Fungible Token (NFTs), served as a gateway to crypto, helping to fuel its rise—and then became one of its victims
• How NFTs were originally about the democratization of artistic creation and had the potential to help artists across the globe
• Sam Bankman-Fried’s (SBF) backstory, his interest in “effective altruism” and the “earn-to-give” philosophy, and his early career at a Wall Street trading firm where he developed his obsession with taking huge risks
• Did SBF believe his lies? Was he self-deceived?
• How SBF used his autistic-like behavior to convince people he was a misunderstood genius
• Risk-neutral behavior and crypto
• Effective altruism, utilitarianism, and deontological ethics
• Comparisons of SBF with Elizabeth Holmes
• SBF’s arrest and dramatic trial. Rather than plea guilty and take a deal, Sam, true to his risk-taking nature, gambled it all and took his case to trial
• The parallels between crypto and the problematic financial system it was meant to replace
• While crypto promised to dislodge predatory middlemen, all it did was create new ones, with less oversight and many of the same painful fees
• How the 2022 crypto crash closely mirrored the 2008 financial crisis. The 2008 bubble had been caused by risky mortgage loans repackaged into financial derivatives. The 2022 crypto crash was likewise brought down by hidden, interconnected chains of leverage, in which hedge funds, exchanges, and lenders played dangerous money games because they thought the market might keep expanding forever.

If you enjoy the podcast, please show your support by making a $5 or $10 monthly donation.

The amazing Gaia mission to chart stars in the Milky Way Galaxy is also an expert asteroid hunter. Now, astronomers are reporting its success at spotting more moons of asteroids in our solar system. Once the Gaia data from its release 3 are confirmed, those observations will add 352 more binary asteroids to the known count. That nearly doubles the known number of asteroids with moons and previous Gaia data releases also revealed asteroids in its survey.

The spacecraft’s observations uncovered these possible moons around at least 350 asteroids—making them binary systems. That’s in addition to the known binary asteroids—those objects with companions—that it found with its precise sweeps of the sky. The most recent discoveries come from “blind” astrometric surveys (not necessarily directed at any one part of the sky or specific objects) and show that the collection of asteroids is more complex than we thought.

“Binary asteroids are difficult to find as they are mostly so small and far away from us,” says Luana Liberato of Observatoire de la Côte d’Azur, France, lead author of a new study announcing Gaia’s results. “Despite us expecting just under one-sixth of asteroids to have a companion, so far we have only found 500 of the million known asteroids to be in binary systems. But this discovery shows that there are many asteroid moons out there just waiting to be found.”

The binary near-Earth asteroid 65803 Didymos and its moon Dimorphos. Imaged by the Double Asteroid Redirection (DART) spacecraft. Gaia is finding more such binaries in the Solar System. Courtesy NASA/Johns Hopkins APL. Gaia Astrometry for the Win

Astrometry used to be thought of as a fairly “boring” part of astronomy. It’s the precision study of the positions of objects in space. Not quite as exciting as finding new comets or charting new galaxies. Yet, it’s an important branch because, without it, we’d have more difficulty finding things like planets around stars. Those are notoriously difficult (if not impossible) to detect using imaging techniques. However, a star’s position in space changes thanks to gravitational tugs from its planets. Thanks to precise astronometric measurements made by Gaia and other instruments, astronomers can detect the minute shifts in stellar positions.

It turns out that Gaia’s astrometric abilities are precise enough to detect similar shifts in the positions of asteroids. For example, in one of its data releases, the spacecraft’s survey pinpointed the positions and motions of more than 150,000 asteroids. Those positions were precise enough that researchers could detect very tiny shifts in their positions over time. Those shifts meant that the asteroids had companions influencing their positions and motions in space.

Not only did the instruments onboard Gaia measure those positions accurately, they also allowed scientists to do “asteroid chemistry”. The data it gathered consisted of spectra of the reflected light from each asteroid. The spectra show the fingerprints of an asteroid’s surface composition. Future measurements are expected from the spacecraft in the coming years as part of its data release 4.

A chart of Gaia asteroid science. Courtesy ESA. Why Asteroids?

The Solar System is a collection of objects consisting of one star, multiple planets, moons, rings, comets, and asteroids. Those last two categories sometimes get lumped together as “leftovers of planet formation.” They are, indeed, the materials that didn’t coalesce into planets and moons. As such, they also contain a lot of information about what conditions were like in the original nebula where the Sun and planets formed. That includes insight into the distribution of rocky and icy materials. In addition, as we’re seeing with the Gaia measurements, binary asteroids appear to be a normal part of that population of small rocky/icy bodies that exist throughout the Solar System.

Asteroids are sorted into “families” based on their orbits and other characteristics. The largest collection exists in the Asteroid Belt, which lies between Mars and Jupiter. There are also other collections that orbit the Sun at other distances—such as the near-Earth asteroids. As we see with the discovery of more binary asteroids, not all of these objects orbit alone. Binaries show us that asteroids can collide after formation, re-coalesce, and interact with each other in space. And, the Gaia mission is showing that performing precise astrometric measurements of objects in our solar system is opening up a new avenue of asteroid studies. It should help answer the many questions about asteroids, their moons, and the evolution of their orbits.

The Future of Asteroid Moon Studies

Future studies of these objects (whether binary or singular) lie with Gaia and other telescope observations. Those should help settle some theories in the scientific community about how binary asteroids form. At the moment, there are several ideas, including creating rubble piles of material orbiting together after some catastrophic event. Another theory suggests that asteroids are what’s left after a moon or other body breaks up by collision or gravitational interaction with a larger body. Any fresh insights will depend on more data from Gaia and other studies of these fascinating objects.

So, far from being a boring “bookkeeping” exercise in astronomy, thanks to Gaia, astrometry enables astronomers and planetary scientists to further our knowledge of the solar system and its complex collection of objects.

For More Information

Gaia Spots Possible Moons Around Hundreds of Asteroids
Gaia Mission
Astrometry Overview

The post Gaia Finds Hundreds of Asteroid Moons appeared first on Universe Today.

UPDATE: I looked up Dawkins’s FB account and got this, showing no posts at all, even the ones from 2017 mentioned below:

I received this message from both the UK and US. Apparently Richard Dawkins’s Facebook account, except for two entries dating back to 2017, has been deleted because he criticized the Olympics allowing putative XY boxers, which are likely phenotypically and genetically male, to box against biological women in the Olympics. (See my posts here and here.)

I haven’t been much on the internet since I’m sightseeing and also have only sporadic connection to the world, so I’m not sure how this issue has shaken out. There are debates about whether the two boxers in question were of XY chromosome constitution, had high levels of testosterone (they had previously been disqualified in other competitions), or had genetic disorders of sex development (DSDs).

But regardless, to ban someone’s account for expressing the opinion that genetically male boxers shouldn’t fight against biological women is unconscionable. mRichard said that one of the boxers is “XY undisputed,” and since I’ve been out of touch, that may be the case.  And if that is the case, then there is a real debate to be had.

There’s a general debate to be had about these boxers anyway since, last I heard, people were arguing about every aspect of the two is subject to dispute.

Facebook botched this one very badly, and should restore Dawkins’s account.  What he wrote below is apparently on Twitter.

If some knowledge about these boxers has become generally accepted in the past week, please add it below. I know that Colin Wright has been following the case and wrote a Substack post a week ago called “Fact vs. fiction: Olympic boxer Imane Khelif is male and should not be allowed to fight women.” He also has a new post, which I haven’t yet read, subtitled, “There are no good reasons to doubt the IBA’s claim that both Khelif and Yu Ting have XY chromosomes.”

Richard’s Facebook post

Meanwhile, in Dobrzyn, Hili is becoming demanding, as cats can be:

Hili: You have to renounce your immunity. A: What immunity is that? Hili: The one which protects you from accountability for an empty bowl.

Hili: Musisz zrzec się immunitetu.
Ja: Jakiego znowu immunitetu?
Hili: Chroniącego cię przed odpowiedzialnością za pustą miseczkę.

Supermassive Black Holes (SMBHs) are located in the centers of large galaxies like ours. When they’re actively feeding, they produce more light and are called active galactic nuclei (AGN). But their details are difficult to observe clearly because large clouds of gas block our view.

The JWST was built just for circumstances like these.

New research published in the Monthly Notices of the Royal Astronomical Society (MNRAS) presents JWST observations of an SMBH in a galaxy about 70 million light-years away. The telescope found polar dust surrounding the SMBH. It was outside the expected torus of dust that directly accretes onto the black hole that researchers call the accretion disk. The polar dust is heated, but rather than being heated by the radiation coming from the heated accretion disk, the gas is heated when by energetic shock waves that come from relativistic jets.

The research is titled “Dust beyond the torus: revealing the mid-infrared heart of local Seyfert ESO 428-G14 with JWST/MIRI.” The lead author is Houda Haidar, a PhD student in the School of Mathematics, Statistics, and Physics at Newcastle University in the UK. Houda and her co-researchers are members of GATOS, the Galactic Activity, Torus, and Outflow Survey. According to the GATOS website, GATOS is an international team using the JWST to “crack the enigma that is active galactic nuclei.”

“Having the opportunity to work with exclusive JWST data and access these stunning images before anyone else is beyond thrilling,” said Houda. “I feel incredibly lucky to be part of the GATOS team. Working closely with leading experts in the field is truly a privilege.”

This is the JWST’s first look at the galaxy in question, ESO 428-G14, but it’s not astronomers’ first look at it. They’ve been observing the galaxy—called a Seyfert galaxy because of its high luminosity—for decades. The astronomy community has used several telescopes to examine the galaxy, including ALMA and the Hubble, and that data forms part of this work.

The challenge in observing this AGN, and many others like it, is dust. The thick, extensive clouds of dust and gas that eventually feed the black hole block our view of it. The JWST’s job description is to pierce dust like this and get a clearer look into these obscured regions.

The JWST has four primary science themes, one of which is Galaxies Over Time. A combination of processes drives galaxy evolution, and active galactic nuclei are part of the picture.

Active galactic nuclei can emit relativistic jets of material from their poles that, in some cases, can extend hundreds of millions of light-years into space. ESO 428-G14 is no different; it emits radio jets from its poles. Astrophysicists know that gravitational and magnetic forces are behind these jets, but the exact mechanism behind them is unknown and is an active area of research.

The jets could be the key to understanding SMBHs, how they recycle material in galaxies, and the dust that accumulates around them in a torus. “For decades, the dusty torus has been held responsible for the dichotomy between type?1 and type?2 active galactic nuclei (AGN), forming the keystone of AGN unification,” the authors write.

The unified AGN model states that types 1 and 2 AGN are differentiated by their viewing angles rather than by any fundamental differences between the two. Type 1 is viewed more face-on relative to the dust torus, displays broad emission lines in its spectra, and has visible accretion disks. Type 2 is viewed more edge-on relative to the torus, has narrow emission lines, and has obscured accretion disks.

Some AGN have polar dust that’s separate from their torus dust. Many models predict that this dust is energized by the jets that come out of its poles. “However, little is known about its characteristics, spatial extent, or connection to the larger scale outflows,” the researchers write in their paper. This is “the first JWST/MIRI study aimed at imaging polar dust by zooming on to the centre of ESO 428-G14.”

The JWST found extended Mid-infrared emissions that extended to 650 light-years from the AGN. The structure of this polar dust is co-linear with a radio jet emitted by the AGN. But the dust is perpendicular to a molecular gas lane that’s feeding the AGN and obscuring it. This is important evidence for the presence of polar dust. “Its morphology bears a striking resemblance to that of gas ionized by the AGN,” the authors write.

This figure from the research illustrates some of the results. The left panel is a JWST/MIRI F1000W image showing the MIR structure of the circumnuclear disc along with the small-scale nuclear extensions. The right panel is a Hubble image of the same in optical light. The inset is the radio jet coming from the AGN. Image Credit: Haidar et al. 2024.

This brings us back to the ongoing debate about how AGN energize the gas and dust in their environment. What role do the jets play vs what role does electromagnetic radiation from the AGN play? One line of evidence shows that dust absorbs electromagnetic radiation emitted by the heated dust in the accretion disk.

However, the new JWST images show that much of the polar dust emission is extended and spread out along the jets’ paths. This clearly implies that the jets are responsible for heating and shaping the dust, and radiation from the AGN plays a lesser role. The accretion dust and the polar dust have different temperatures, and that provides clues about how different parts of the AGN are heated differently. Jet-induced shocks could be responsible for the heat differences between the polar dust and the accretion dust.

“There is a lot of debate as to how AGN transfer energy into their surroundings. We did not expect to see radio jets do this sort of damage. And yet here it is!” said Dr David Rosario, Senior Lecturer at Newcastle University and co-author of the study.

The post The JWST Reveals the Nature of Dust Around an Active Galactic Nuclei appeared first on Universe Today.

The covid-19 variant JN.1 may have been able to evade antibodies and spread globally due to one critical mutation to its spike protein

A new artificial intelligence model can predict how different proteins may bind to DNA.

Solid-state electrolytes have been explored for decades for use in energy storage systems and in the pursuit of solid-state batteries. These materials are safer alternatives to the traditional liquid electrolyte -- a solution that allows ions to move within the cell -- used in batteries today. However, new concepts are needed to push the performance of current solid polymer electrolytes to be viable for next generation materials.

Physicists have used Doppler-shifted nuclear resonant absorbers to form a nuclear frequency comb, enabling a quantum memory in the notoriously difficult X-ray range.

A research team has constructed an unprecedented chiral-structured interface in perovskite solar cells, which enhances the reliability and power conversion efficiency of this fast-advancing solar technology and accelerates its commercialization.

A research team reports a pioneering plasma-catalytic process for the hydrogenation of CO2 to methanol at room temperature and atmospheric pressure. This breakthrough addresses the limitations of traditional thermal catalysis, which often requires high temperatures and pressures, resulting in low CO2 conversion and methanol yield.

Most of us learned about butterfly metamorphosis as a kid -- a wriggly caterpillar molts its skin to form a tough chrysalis and emerges as a beautiful butterfly. But how exactly do chrysalises stay anchored as the butterfly brews within? Research shows that, despite their silks being weak and thin on their own, caterpillars can expertly spin them into chrysalis support structures resembling hook-and-loop fasteners and multi-strand safety tethers.

Microalgae such as the diatom Odontella aurita and the green alga Tetraselmis striata are especially suitable as 'biofactories' for the production of sustainable materials for 3D laser printing due to their high content in lipids and photoactive pigments. An international research team has succeeded for the first time in manufacturing inks for printing complex biocompatible 3D microstructures from the raw materials extracted from the microalgae.

Researchers invented a technique that uses a specialized light projector and a photosensitive chemical additive to imprint two- and three-dimensional images inside any polymer. The light-based engraving remains in the polymer until heat or light are applied, which erases the image and makes it ready to use again. The technology is intended for any situation where having detailed, precise visual data in a compact and easily customizable format could be critical, such as planning surgeries and developing architectural designs.

Researchers invented a technique that uses a specialized light projector and a photosensitive chemical additive to imprint two- and three-dimensional images inside any polymer. The light-based engraving remains in the polymer until heat or light are applied, which erases the image and makes it ready to use again. The technology is intended for any situation where having detailed, precise visual data in a compact and easily customizable format could be critical, such as planning surgeries and developing architectural designs.

Machine learning is a powerful tool in computational biology, enabling the analysis of a wide range of biomedical data such as genomic sequences and biological imaging. But when researchers use machine learning in computational biology, understanding model behavior remains crucial for uncovering the underlying biological mechanisms in health and disease. Researchers now propose guidelines that outline pitfalls and opportunities for using interpretable machine learning methods to tackle computational biology problems.

In the centre of a distant galaxy, a supermassive black hole has swallowed up a star 9 times the sun’s mass in the biggest and brightest such cosmic meal we’ve ever seen

A zigzag design can maximise how much heat walls radiate into space, while minimising heat absorption from the ground