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Researchers develop method to 'hear' defects in promising nanomaterial

Matter and energy from Science Daily Feed - Wed, 10/23/2024 - 10:07am
An international research team has pioneered a new technique to identify and characterize atomic-scale defects in hexagonal boron nitride (hBN), a two-dimensional (2D) material often dubbed 'white graphene' for its remarkable properties. This advance could accelerate the development of next-generation electronics and quantum technologies.
Categories: Science

There's a Particle Accelerator at the Center of the Milky Way

Universe Today Feed - Wed, 10/23/2024 - 9:05am

Nestled on the slopes of Cerro La Negra at an elevation of 13,000 feet is an unusual-looking observatory. Known as the High-Altitude Water Cherenkov (HAWC) observatory, it looks like a tightly packed collection of grain silos, which is essentially what it is. But rather than holding grain, the silos are each filled with 188,000 liters of water and four photomultiplier tubes. While it’s an unusual setup, it’s what you need to observe high-energy gamma rays from deep space.

Rather than observing the gamma rays directly, the observatory uses an effect known as [Cherenkov radiation. Essentially, when a high-energy gamma ray strikes Earth’s atmosphere, it triggers the emission of a shower of particles moving at nearly light speed. They move so fast that they travel faster than light can move through water. So when these particles pass through a water silo, they emit Cherenkov radiation. HAWC is particularly sensitive to TeV gamma rays, which are the highest energy gamma rays produced in the cosmos. And with such a large number of detectors, HAWC can pinpoint the origin of these TeV gamma rays better than any other observatory, as a recent study shows.

It’s a bit rare for a high-energy gamma ray to strike Earth, so the team gathered seven years of observations, capturing 100 gamma ray events, each with an energy of more than 100 TeV. While that doesn’t sound like a lot, it is enough data for the team to determine their origin. The particles are coming from the center of our galaxy! Of course, many of you won’t be the least surprised. After all, there is a supermassive black hole in that area, so naturally it would produce high-energy particles. But this discovery helps us understand what’s going on.

The HAWC observatory seen in 2014. Credit: Wikipedia user Jordanagoodman

In order for TeV gamma rays to reach us across 30,000 light years, our galactic black hole must produce even higher energy particles. Specifically, it must produce protons in the PeV energy range. Peta electron volts, which is a thousand times more energy than the gamma rays we see. These PeV protons then collide with interstellar gas molecules to produce gamma rays. This means there must be a mystery PeVatron source. We know that PeV protons can be produced in the most violent astrophysical phenomena, such as supernovae and black hole mergers, but these can’t explain what we observe.

To further understand the source, the team looks forward to the construction of the Southern Wide-field Gamma-ray Observatory (SWGO), which will be a facility similar to HAWC, but in the Atacama region of northern Chile. By combining observations from both, we should be able to localize the galactic source of PeV protons.

Reference: Albert, A., et al. “Observation of the Galactic Center PeVatron beyond 100 TeV with HAWC.” The Astrophysical Journal Letters 973.1 (2024): L34.

The post There's a Particle Accelerator at the Center of the Milky Way appeared first on Universe Today.

Categories: Science

DNA has been modified to make it store data 350 times faster

New Scientist Feed - Wed, 10/23/2024 - 9:00am
Researchers have managed to encode enormous amounts of information, including images, into DNA at a rate hundreds of times faster than was previously possible
Categories: Science

Google tool makes AI-generated writing easily detectable

New Scientist Feed - Wed, 10/23/2024 - 9:00am
Google DeepMind has been using its AI watermarking method on Gemini chatbot responses for months – and now it’s making the tool available to any AI developer
Categories: Science

Energy expert Vaclav Smil on how to feed the world without trashing it

New Scientist Feed - Wed, 10/23/2024 - 9:00am
The systems we use to produce food have many problems, from horrifying waste to their dependence on fossil fuels. Vaclav Smil explains how to fix them
Categories: Science

A supernova may have cleaned up our solar system

New Scientist Feed - Wed, 10/23/2024 - 7:55am
A nearby star that exploded some 3 million years ago could have removed all dust smaller than a millimetre from the outer solar system
Categories: Science

Waiting to fly, and more news

Why Evolution is True Feed - Wed, 10/23/2024 - 7:30am

I was up at 4 a.m. to get to Midway two hours before my flight to Vegas (yes, I’m compulsively early, but never in my life have I missed a flight, train, or bus).

Thanks to TSA Pre-Check, I breezed through security in two minutes, and, thank Ceiling Cat, did not get groped.  At the first gate I encountered there was a crowd of older men, many in wheelchairs, and all wearing hats and tags around their neck. The gate was also full of men in orange shirt whose duty was to push the men in wheelchairs onto the plane.  On the table to the side were free donuts and coffee (I did not partake).

I asked one of the women shepherding the men what was going on. She replied that this was an “Honor Flight”.  I asked what that meant, and learned that, once a month, Southwest flies a planeload of veterans—most from Vietnam but a few from WWII—to D.C. for a ceremony, presumably at the Vietnam Veterans Memorial.  After that, Southwest flies them home. It’s all for free, and there’s a waiting list.

This is why Southwest is my favorite airline, though it plans some changes in 2025. The passengers on the Honor Flight.

To be sure, I felt a bit weird about honoring men fighting and dying in a futile and unjust war (I was a conscientious objector and worked in a hospital instead of going into the srevice), but on the other hand I have the customary respect for people who risk their lives at the behest of their country.

Now I’m cooling my heels at Midway Airport with about an hour until boarding the four-hour Dishonor Flight to Vegas. I have two Dunkin Donuts and a very large coffee, as well as a copy of a book I’m reviewing and a short novel to read on the plane: The Vegetarian, by Han Kang.

I’ll add some news that I read this morning.

*At the NYT, famed election prognosticator Nate Silver gives his gut feeling about who will win the election. I’ll quote a bit (the piece is archived here.) It’s not pretty:

Yet when I deliver this unsatisfying news, I inevitably get a question: “C’mon, Nate, what’s your gut say?”

So OK, I’ll tell you. My gut says Donald Trump. And my guess is that it is true for many anxious Democrats.

But I don’t think you should put any value whatsoever on anyone’s gut — including mine. Instead, you should resign yourself to the fact that a 50-50 forecast really does mean 50-50. And you should be open to the possibility that those forecasts are wrong, and that could be the case equally in the direction of Mr. Trump or Ms. Harris.

Nate’s reasons:

Instead, the likely problem is what pollsters call nonresponse bias. It’s not that Trump voters are lying to pollsters; it’s that in 2016 and 2020, pollsters weren’t reaching enough of them.

Nonresponse bias can be a hard problem to solve. Response rates to even the best telephone polls are in the single digits — in some sense, the people who choose to respond to polls are unusual. Trump supporters often have lower civic engagement and social trust, so they can be less inclined to complete a survey from a news organization. Pollsters are attempting to correct for this problem with increasingly aggressive data-massaging techniques, like weighing by educational attainment (college-educated voters are more likely to respond to surveys) or even by how people say they voted in the past. There’s no guarantee any of this will work.

If Mr. Trump does beat his polling, there will have been at least one clear sign of it: Democrats no longer have a consistent edge in party identification — about as many people now identify as Republicans.

. . . There’s also the fact that Ms. Harris is running to become the first female president and the second Black one. The so-called Bradley effect — named after former Los Angeles Mayor Tom Bradley, who underperformed his polls in the 1982 California governor’s race, for the supposed tendency of voters to say they’re undecided rather than admit they won’t vote for a Black candidate — wasn’t a problem for Barack Obama in 2008 or 2012. Still, the only other time a woman was her party’s nominee, undecided voters tilted heavily against her. So perhaps Ms. Harris should have some concerns about a “Hillary effect.”

It’s hard for me to believe that people would take sex and race into account these days (Silver apparently believes that sex is more important than race), but if Harris loses, we’ll never know.  Finally, Silver proffers a spoonful of sugar by theorizing about how Harris could underperform in the polls and win the election. One more prediction, and you can read the whole article at the archived link above:

Here’s another counterintuitive finding: It’s surprisingly likely that the election won’t be a photo finish.

With polling averages so close, even a small systematic polling error like the one the industry experienced in 2016 or 2020 could produce a comfortable Electoral College victory for Ms. Harris or Mr. Trump. According to my model, there’s about a 60 percent chance that one candidate will sweep at least six of seven battleground states.

It’s no secret that I’m not a huge fan of Harris, who I think would not be the candidate if we had longer to vet the Democrats, but I’m even less of a fan of Trump, and would be embarrassed before foreigners to admit that someone who dances for half an hour onstage, boasts about grabbing women’s genitals, is subject to five indictments, and curses badly about Harris (I believe I heard him say, before an office, that she was a “shit Vice President—that such a person could be elected to the highest office in the land.

*And the Free Press reports that a lot of the $90 million donated to Black Lives Matter after George Floyd’s death has been embezzled, and for hedonistic purposes:

The spectacular rise and fall of BLM has surprisingly little in common with earlier civil rights campaigns, other than, perhaps, good intentions. How BLM’s leaders exploited George Floyd’s murder to raise millions that they then put into their own pockets more closely resembles the stories of famous grifters like Elizabeth Holmes of Theranos or Sam Bankman-Fried’s foray into “effective altruism.”

. . . . And BLM four years later? It looks like little more than a hustle.

The latest proof point came earlier this month when Tyree Conyers-Page—a.k.a. Sir Maejor Page, the 35-year-old former leader of the BLM chapter of Greater Atlanta—was sentenced to 42 months in federal prison for money laundering and wire fraud. Pocketing the $450,000 raised from 18,000 donors to “fight for George Floyd” and the “movement,” Page spent lavishly on himself, splurging on tailored suits, nightclub bar tabs, an evening with a prostitute, and, as he texted to a friend, “a big-ass cribo” that he bought in Ohio after he “won the lottery.”

 . . . There are actually two [parent networks of BLM]: BLM Global Network Foundation and BLM Grassroots. The latter was formed in 2019 as an umbrella organization of local chapters of the group and is co-directed by Melina Abdullah. Since then, media reports have accused Abdullah and other chapter leaders of using Grassroots’ coffers to pay for vacations to Jamaica and her own personal expenses. (She hasn’t been charged with a crime.)

Abdullah has denied the allegations, but at least $8.7 million in donations is unaccounted for. The answer to where the money went may come soon. California attorney general Rob Bonta has demanded that Grassroots turn over delinquent tax filings and late fees before Sunday, October 27. If it doesn’t, the organization’s tax-exempt status will be revoked.

And about BLM Global, which was “founded in July 2013 by activists Patrisse Cullors, Alicia Garza, and Opal Tometi as an online platform in response to the killing of Trayvon Martin by George Zimmerman in 2012.”

As the national face of BLM, Cullors was suddenly in great demand. She inked a deal with Warner Bros. to create animated kids’ programming, documentaries, dramas, and comedies about structural racism and inequality—none of which were ever made. She and the foundation also spent a big chunk of those donations on an enviable real estate portfolio. They acquired a $6 million Los Angeles mansion, which Cullors used in early 2021 for a Biden inauguration party as well as her son’s birthday party. She and BLM Global paid $6.3 million for a mansion in Canada, which they named “the Wildseed Centre for Arts and Activism” (“a transfeminist, queer affirming space politically aligned with supporting Black liberation work across Canada”). They also dropped $3.2 million on four luxury properties, including a 3.2-acre estate in Georgia that boasted a runway for private aircraft. And BLM Global handed out money to a coterie of Cullors’ friends and relatives, including $778,000 for “services” to an arts group run by Damon Turner, the father of Cullors’ son, and $1.6 million to a security firm owned by her brother Paul. The foundation also cut checks totaling $205,000 to a company run by Cullors and her spouse as well as a $211,000 payout to Asha Bandele, the friend who helped Cullors write her memoir.

There’s more, and this is really depressing:

And yet, a husk of BLM still exists, and is focused on what might be the organization’s final cause: anti-Zionism.

About all of this what can one say but “Oy gewalt!”?

Categories: Science

Jesus ‘n’ Mo ‘n’ abrogation

Why Evolution is True Feed - Wed, 10/23/2024 - 6:15am

Today’s Jesus and Mo strip, called “latter,”, came with a list of Qur’anic verses:

2.19, 4.43 and 5.90 if you’re interested.

And yes, what Jesus says is true, as is his riposte when Mo explains abrogation. This is one of the issues that’s an Achilles Heel for Islam, as is the statement by Jesus (Matthew 16:28):

Verily I say unto you, There be some standing here, which shall not taste of death, till they see the Son of man coming in his kingdom.

Jesus, you didn’t come back! (Of course theologians can parse the verse so it appears metaphorical.)

Categories: Science

EMDR Is Still Dubious

Science-based Medicine Feed - Wed, 10/23/2024 - 5:25am

A recent meta-analysis of eye movement desensitization and reprocessing (EMDR) therapy concludes that the evidence “confirms” EMDR is effective in treating depression. It is a great example of the limitations of meta-analysis, and how easy it is to create essentially a false narrative using poor quality research. EMDR was “developed” by Dr. Francine Shapiro in 1987. It is the notion that bilateral […]

The post EMDR Is Still Dubious first appeared on Science-Based Medicine.
Categories: Science

All your questions about Marburg virus answered

New Scientist Feed - Wed, 10/23/2024 - 4:00am
Everything you need to know about Rwanda's outbreak of Marburg virus, which has been described as one of the deadliest human pathogens
Categories: Science

Extremely rare Bronze Age wooden tool found in English trench

New Scientist Feed - Tue, 10/22/2024 - 5:01pm
In a wetland on the south coast of England, archaeologists dug up one of the oldest and most complete wooden tools ever found in Britain, which is around 3500 years old
Categories: Science

10 stunning James Webb Space Telescope images show the beauty of space

New Scientist Feed - Tue, 10/22/2024 - 2:52pm
Maggie Aderin-Pocock, who has worked on the JWST, catalogues the science behind its most stunning images in her new book, Webb's Universe. Here's her pick of the telescope’s best shots
Categories: Science

New Research Reveals Provides Insight into Mysterious Features on Airless Worlds

Universe Today Feed - Tue, 10/22/2024 - 2:30pm

Between 2011 and 2018, NASA’s Dawn mission conducted extended observations of Ceres and Vesta, the largest bodies in the Main Asteroid Belt. The mission’s purpose was to address questions about the formation of the Solar System since asteroids are leftover material from the process, which began roughly 4.5 billion years ago. Ceres and Vesta were chosen because Ceres is largely composed of ice, while Vesta is largely composed of rock. During the years it orbited these bodies, Dawn revealed several interesting features on their surfaces.

This included mysterious flow features similar to those observed on other airless bodies like Jupiter’s moon Europa. In a recent study, Michael J. Poston, a researcher from the Southwest Research Institute (SWRI), recently collaborated with a team at NASA’s Jet Propulsion Laboratory to attempt to explain the presence of these features. In the paper detailing their findings, they outlined how post-impact conditions could temporarily produce liquid brines that flow along the surface, creating curved gullies and depositing debris fans along the impact craters’ walls.

Michael J. Poston, the lead author of the study, is the Group Leader of Laboratory Studies (Space Science) at the SwRI. He was joined by a team of researchers from NASA JPL at the California Institute of Technology (Caltech) and the Airborne Snow Observatories, including Jennifer Scully – a NASA JPL planetary geologist and an Associate on the Dawn science mission team. The paper that describes their findings, “Experimental Examination of Brine and Water Lifetimes after Impact on Airless Worlds,” was published on October 21st in The Planetary Science Journal.

The planetoid Vesta, which was studied by the Dawn probe between July 2011 and September 2012. Credit: NASA

Airless bodies are frequently struck by asteroids, meteorites, and other debris that form impact craters and cause temporary atmospheres to form above them. On icy bodies or those with sufficient amounts of volatile elements (possibly beneath the surface), this will trigger temporary outflows of liquid water. However, water and other volatiles (like ammonia, carbon dioxide, methane, etc.) will lose stability in strong vacuum conditions. For their study, the team sought to examine how long liquid could potentially flow on the surfaces of airless bodies (such as Ceres and Vesta) before refreezing.

To this end, they simulated the pressures that ice on Vesta experiences after a meteoroid impact and how long it would take the liquid released from the subsurface to refreeze. “We wanted to investigate our previously proposed idea that ice underneath the surface of an airless world could be excavated and melted by an impact and then flow along the walls of the impact crater to form distinct surface features,” said Scully in a recent SwRI press release.

To this end, the team placed liquid-filled sample containers in a modified test chamber at NASA JPL to simulate the rapid pressure decreases that occur after an impact on airless bodies. In so doing, they were able to simulate how liquid behaves as the temporary atmosphere created by an impact dissipates. According to their results, the pressure drop was so fast that test liquids immediately and dramatically expanded, ejecting material from the sample containers. As Poston explained:

“Through our simulated impacts, we found that the pure water froze too quickly in a vacuum to effect meaningful change, but salt and water mixtures, or brines, stayed liquid and flowing for a minimum of one hour. This is sufficient for the brine to destabilize slopes on crater walls on rocky bodies, cause erosion and landslides, and potentially form other unique geological features found on icy moons.”

This image of the Cornelia Crater on Vesta shows lobate deposits (right) and curvilinear gullies (indicated by white arrows, left). Credit: SwRI/NASA JPL-Caltech/Poston et al. (2024)

These findings could help explain the origins of similar features on other airless bodies, like Europa’s smooth plains and the spider-like feature in its Manannán impact crater (which is due to “dirty ice” existing alongside “pure” water ice). They could also shed light on post-impact processes on bodies with very thin atmospheres, like Mars. This includes its gullies, which have dark features that flow downhill, and fan-shaped debris deposits that form in the presence of flowing water. Last, the study could support the existence of subsurface water in other inhospitable environments throughout the Solar System.

“If the findings are consistent across these dry and airless or thin-atmosphere bodies, it demonstrates that water existed on these worlds in the recent past, indicating water might still be expelled from impacts,” said Poston. “There may still be water out there to be found.” This could have profound implications for future missions to these bodies, including NASA’s Europa Clipper mission. This mission launched on October 14th, 2024, and will establish orbit around Europa by April 2030.

Further Reading: SwRI, The Planetary Science Journal

The post New Research Reveals Provides Insight into Mysterious Features on Airless Worlds appeared first on Universe Today.

Categories: Science

The mystery of the missing La Niña continues – and we don't know why

New Scientist Feed - Tue, 10/22/2024 - 2:00pm
A climate-cooling La Niña pattern was expected to develop in the Pacific Ocean months ago, but forecasters now say it won't appear until November
Categories: Science

Testing Heat Shields for Different Atmospheres

Universe Today Feed - Tue, 10/22/2024 - 1:50pm

Testing is one of the unsung steps in the engineering process. Talk to any product development engineer, and they will tell you how big of a milestone passing “V&V” – or verification and validation – testing is. Testing is even more critical when you work on equipment meant for the harsh space environment. It is also more challenging to mimic those harsh environments on Earth. Luckily for some of NASA’s more critical upcoming missions, another government agency has a unique test lab to help V&V with some of its most critical components – their heat shields.

That other government agency is the US Department of Energy (DoE), specifically its Sandia National Laboratory. The US’s national labs were initially developed to coordinate nuclear weapons research, but they have since taken on a broader role in the country’s fundamental scientific research efforts. That includes providing test equipment unavailable anywhere else in the world.

One unique test setup at Sandia is known as the solar testing facility. It’s a field with over 200 “heliostats” – giant mirrors that can focus the light from the Sun that they reflect on a particular point. With all of them focused on the same point, it can get as hot as 3,500 times the typical sunlight on an area.

The setup at Sandia isn’t just for testing material – it can also be used for power generation, as show in this video.
Credit – Sandia National Labs YouTube Channel

That area is also one of the selling points of the solar testing facility. It can test pieces of material up to 1 m (3 ft) in diameter. This makes it superior to other test facilities that intend to test the same types of materials, such as those that use arc jets or lasers. Cost is also a consideration, with arc jet or laser testing costing more than $100,000 daily. Comparatively, solar testing costs only $25,000 per day, mainly due to the lower energy costs of operating the heliostats. 

NASA has used all of that testing technology over the last year to test the heat shields of some of its most important missions – the Mars Sample Return (MSR) mission and Dragonfly, the helicopter mission to Titan. Each mission has its challenges, but the materials for their heat shields are the same. Known as a Phenolic impregnated Carbon Ablator, this material has already been successfully used for missions such as Stardust, OSIRIS-REx, and Mar Science Laboratory.

MSR and Dragonfly each have unique challenges that other missions didn’t face. MSR will be carrying a significant payload of samples back to Earth, meaning it will be heavier than the OSIRIS-REx asteroid sample return mission. It will be so heavy that some NASA engineers intentionally bent the test material at Sandia’s test lab to model what happens to material undergoing the force of reentry.

NASA’s reentry testing program is intensive, as discussed in this video.
Credit – BPS.space YouTube Channel

For its part, Dragonfly has to deal with a world with a much thicker atmosphere than Earth itself. Titan’s atmosphere is four times denser than Earth’s. Given the interplanetary speeds at which the mission will be traveling when it reaches orbital insertion, Dragonfly’s accompanying lander will be subjected to both high heat and pressure as it descends onto the Moon’s surface.

Sandia’s lab technicians made a number of improvements to the test setup for the tests, including running gas lines to the sample from the base of the tower to better mimic the atmosphere the heat shields will be encountering. They were also on hand to help with troubleshooting, which included multiple instances where some fiber surrounding the sample caught fire before the test could be completed.

V&V testing rarely completes without some adjustments and occasionally without any fires. Testing on this type of setup is just part of NASA’s test plan for the heat shield use case, with other tests happening elsewhere. Given the importance of this particular material to the overall success of these critical missions, the more testing they are able to undergo here on Earth, the better.

Learn More:
Sandia National Laboratory – Sandia tests heat shields for space
UT – NASA is Continuing to Build the Titan Dragonfly Helicopter. Here are its Rotors
UT – NASA and ULA Successfully Test a Giant Inflatable Heat Shield That Could Land Heavier Payloads on Mars
UT – An Innovative Heat Shield That Doesn’t Need to Be Replaced Between Missions

Lead Image:
Smoke billowing off NASA’s heat shield material during a recent test at Sandia National Laboratories’ National Solar Thermal Test Facility.
Credit – Photo by Craig Fritz

The post Testing Heat Shields for Different Atmospheres appeared first on Universe Today.

Categories: Science

This Early Impact Devastated Life then Gave it a Boost

Universe Today Feed - Tue, 10/22/2024 - 1:13pm

Most of us know about the impact that wiped out the dinosaurs about 66 million years ago. It’s a scientific fact that’s entered mainstream knowledge, maybe because so many of us shared a fascination with dinosaurs as children. However, it’s not the only catastrophic impact that shaped life on Earth.

There was an even more ancient one about 3.26 billion years ago, and its repercussions shaped early life in a unique way.

The impact event is called S2, and it took place during Earth’s Archean Eon. The Archean is the second of Earth’s four geological eons, spanning from 4,031 to 2,500 Mya (million years ago). A series of significant changes took place during the Archean, including the formation of Earth’s crust, the emergence of the first continents, and the development of a reducing atmosphere suitable for the first simple lifeforms.

When the S2 impactor struck, Earth life was simple and microbial. The impact had a powerful effect on our planet’s early living things, and new research examines what happened. It’s titled “Effect of a giant meteorite impact on Paleoarchean surface environments and life,” and it’s published in The Proceedings of the National Academy of Sciences. The lead author is Nadja Drabon, an assistant professor in the Department of Earth and Planetary Sciences at Harvard University.

“We think of impact events as being disastrous for life,” Drabon said. “But what this study is highlighting is that these impacts would have had benefits to life, especially early on … these impacts might have actually allowed life to flourish.”

Nadja Drabon, Dept. of Earth and Planetary Sciences, Harvard.

Drabon and her fellow researchers performed painstaking, detailed work to get their results. They travelled to the Barberton Greenstone Belt in South Africa to do their fieldwork. The Belt contains some of the oldest exposed rocks on Earth, and those rocks hold some of the oldest traces of life on Earth. Barberton also holds evidence of at least eight ancient impacts, including S2. Drabon and her team examined rock samples centimetres apart and analyzed their geochemistry, sedimentology, and carbon isotope compositions.

This figure from the research shows some of the rocks the team worked with. (A) is an overview of the Umbaumba section showing, from base to top, black-and-white banded chert (BWBC), S2, fallback layer, and BWBC. (B) shows the S2 spherule bed, (C) shows fine laminations in the fallback layer, (D) shows the BWBC below S2, and (E) shows alternating siliciclastic and siderite-rich chert beds. (F) shows laminated carbonaceous chert below S2 in the Umbaumba section. Red arrows indicate fractures filled by chert. (G) shows clots of carbonaceous matter and other siliciclastic debris from the fallback later in the Umbaumba section. Image Credit: Drabon et al. 2024.

They were able to paint a picture of the momentous day over three billion years ago when an extremely large carbonaceous chondrite 37-58 km in diameter, or 200 times larger than the dinosaur-killing Chicxulub impactor, struck Earth.

It started with a tsunami.

“Picture yourself standing off the coast of Cape Cod, in a shelf of shallow water. It’s a low-energy environment without strong currents. Then all of a sudden, you have a giant tsunami, sweeping by and ripping up the sea floor,” said Drabon.

The ocean was mixed up, and the tsunami carried debris from the land into the oceans. The catastrophic impact generated an enormous amount of heat, boiling away the uppermost layer of the ocean and heating the atmosphere. Next came a thick cloud of dust that prohibited any photosynthesis.

This was a dismal yet brief period in Earth’s history. But life has repeatedly shown how resilient it is. Earth’s primitive bacteria quickly bounced back from the cataclysm.

The impact stirred up iron and mixed deep Fe²+-rich waters with shallow Fe²+-poor waters. Fe²+ is an essential nutrient, and along with phosphorous released from the vaporized meteorite and increased weathering from the tsunami, these two nutrients fuelled life’s rebound.

According to the researchers’ analysis, all of this iron triggered a great flourishing of iron-metabolizing bacteria. This bias toward iron-loving life didn’t last, however, and equilibrium eventually returned. But the event is still a key piece in the puzzle of life on Earth. Despite the cataclysmic effect of giant impacts, they can provide some benefits. (There’s some evidence that meteorites delivered the building blocks of life to Earth.)

This figure from the research shows the stratigraphic layers of the Bruce’s Hill and Umbaumba locations. The inset shows the top of the fallback layer. Image Credit: Drabon et al. 2024.

“The recovery of life would have been fueled by an increase in ferrous iron in the photic zone and enhanced nutrient (especially phosphorous) availability, both indicated by geochemical data,” the authors explain in their research.

“We think of impact events as being disastrous for life,” Drabon said. “But what this study is highlighting is that these impacts would have had benefits to life, especially early on … these impacts might have actually allowed life to flourish.”

The researchers say that events immediately following the impact followed a tight timeline. The heat melted rock into spherules, and they were deposited just before or concurrent with the tsunami deposit. After the spherules and tsunami debris settled, the fallback layer quickly formed. That layer consists of rock lofted into the air by the impact.

“Altogether, the spherule beds and fallback deposits (1.3 to 5 m of strata) were likely deposited within no more than a few days—a geological instant,” the authors write in their research. “In this limited time period, the impact-initiated tsunami ripped up the sea floor, disturbed coastal benthic biosystems, mixed the water column, washed debris from coastal areas into the sea, and caused turbid conditions.”

S2, and probably other large impacts during the early Archean, seem to have had mixed effects on life. For some, the increased nutrients were a boon; for others, the thick dust cloud inhibited photosynthesis. “The tsunami, ocean evaporation, and darkness most severely affected phototrophs in surface waters, but chemoautotrophs in the lower water column and hyperthermophiles would likely have been less influenced,” the authors explain.

Other research into S2 suggests that the impact had other effects. Several studies suggest that it triggered volcanic activity. It may have also generated hydrothermal fields at the impact site, which could have added additional Fe²+ to the environment. It may even have generated tectonic activity.

S2 is just one example of the impacts that shaped life’s trajectory on Earth. Archean rocks contain evidence of at least 16 ancient impacts with bolides larger than 10 km. All of these likely generated severe though short-lived effects.

“Our work suggests that on a global scale, early life may have benefitted from an influx of nutrients and electron donors, as well as new environments, as a result of major impact events,” the researchers conclude.

The post This Early Impact Devastated Life then Gave it a Boost appeared first on Universe Today.

Categories: Science

Mark Weinstein — The Social Reset: Big Tech, Mental Health, and the Future of Connection

Skeptic.com feed - Tue, 10/22/2024 - 12:58pm
https://traffic.libsyn.com/secure/sciencesalon/mss479_Mark_Weinstein_2024_10_22.mp3 Download MP3

Big Tech is driving us, our kids, and society mad. In the nick of time, Restoring Our Sanity Online presents the bold, revolutionary framework for an epic reboot. What would social media look like if it nourished our critical thinking, mental health, privacy, civil discourse, and democracy? Is that even possible?

Restoring Our Sanity Online is the entertaining, informative, and frequently jaw-dropping social reset by Mark Weinstein, contemporary tech leader, privacy expert, and one of the visionary inventors of social networking.

This book is for all of us. Casual and heavy users of social media, parents, teachers, students, techies, entrepreneurs, investors, and elected officials. Restoring Our Sanity Online is the catapult to an exciting, enriching, and authentic future. Readers will embark on a captivating journey leading to an inspiring and actionable reinvention.

Restoring Our Sanity Online includes thought-provoking insights including:

  • Empowering You―Social Media User, Content Creator
  • In The Crosshairs: Privacy And Anonymity
  • Saving Our Kids From The Abyss
  • Surprise! Social Media Can Be Good For Your Mental Health
  • Is AI The High-Tech Tattletale In Your Social Experience?
  • Lifting the Veil On Bots and Trolls
  • Facts, Opinions, Lies―Who Decides?
  • Web3 Is Here―What The Heck Is It?

Mark Weinstein is a world-renowned tech entrepreneur, privacy expert, and one of the visionary inventors of social networking, including SuperFamily and SuperFriends, two of the earliest social networks. In 2016 he founded MeWe, the Facebook alternative with the industry’s first Privacy Bill of Rights. MeWe’s membership grew to nearly 20 million users worldwide, whose advisory board includes Sir Tim Berners-Lee, the inventor of the Web; Steve “Woz” Wozniak, co-founder of Apple; Sherry Turkle, MIT academic and tech ethics leader; and Raj Sisodia, co-founder of the Conscious Capitalism movement. Mark is frequently interviewed and published in major media including the Wall Street Journal, The New York Times, Fox, CNN, BBC, PBS, Newsweek, Los Angeles Times, The Hill, and many more worldwide. He covers topics including social media, privacy, AI, free speech, antitrust, and protecting kids online. A leading privacy advocate, Mark’s landmark 2020 TED Talk, “The Rise of Surveillance Capitalism,” exposed the many infractions and manipulations by Big Tech, and called for a privacy revolution. Mark has also been listed as one of the “Top 8 Minds in Online Privacy” and named “Privacy by Design Ambassador” by the Canadian government. His new book is Restoring Our Sanity Online: A Revolutionary Social Framework.

Shermer and Weinstein discuss:

  • Amid growing concerns over targeting, bullying, hate, boosted misinformation, bots and trolls, AI, privacy violations, and democracy disruption, can we really “restore our sanity online?”
  • As an early inventor of social networking, have you been shocked by the direction social media has taken since launching SuperFamily and SuperFriends in 1998?
  • How do we combat the mental health crisis associated with social media, particularly among teens?
  • How can parents take charge of the runaway train which is their kids on social media?
  • You’ve said the Surgeon General’s recommendation of putting warning labels on social media won’t be effective at protecting kids. What will?
  • Your book has a chapter that says social media can be good for our mental health … You must be kidding!
  • As Meta, X, Snap, and other Big Tech increasingly utilize AI, how will AI impact the future of social media?
  • How will AI chatbots and “AI Friends” affect our personal relationships?
  • Web3 promises to fix the problems with social media—privacy, data ownership, elimination of targeting, etc. What should people know about Web3? Is that too good to be true?
  • How do you envision the future of privacy and anonymity on social media?
  • How do we defeat bots and trolls? Are they going to destroy democracy?
  • While conducting research for the book, how did you discover the shared patterns between Big Agriculture, Big Energy, and Big Tech?
  • What lessons can be gleaned from Big Ag and Big Energy that we can apply to Big Tech?
  • The book’s subtitle is “A Revolutionary Social Framework” and in chapter seven you introduce “Restoration Networks.” What’s so revolutionary about these?
  • Why should social platforms create a more equitable creator economy?
  • How can the tenets of Conscious Capitalism, often associated with retail companies like Patagonia, be applied to social networks?
  • Can social media really function successfully without Surveillance Capitalism?

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

Categories: Critical Thinking, Skeptic

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Woman scanned her brain 75 times to see how birth control changes it

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A neuroscientist underwent dozens of brain scans over three months to better understand the neurological effects of hormonal contraceptives
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NASA reveals prototype telescope for gravitational wave observatory

Matter and energy from Science Daily Feed - Tue, 10/22/2024 - 12:41pm
NASA has revealed the first look at a full-scale prototype for six telescopes that will enable, in the next decade, the space-based detection of gravitational waves.
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