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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

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

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.

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

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.

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.

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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.

A researcher who underwent dozens of brain scans discovered that the volume of her cerebral cortex was 1 per cent lower when she took hormonal contraceptives

A neuroscientist underwent dozens of brain scans over three months to better understand the neurological effects of hormonal contraceptives

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.

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.

A new artificial intelligence-based system can accurately assess the chromosomal status of in vitro-fertilized (IVF) embryos using only time-lapse video images of the embryos and maternal age, according to a new study.

Chemists have developed a new theoretical framework for more accurately predicting the behavior of catalysts. The study reveals how conditions such as temperature and pressure can change a catalyst's structure, efficiency, and even the products it makes -- and can potentially be used to control reaction outcomes.

Disc golf is a sport growing in popularity, but there hasn't been much research into the best techniques -- until now. Researchers and disc golf enthusiasts have determined the best thumb position on a disc to maximize angular and translational speeds.

The emergence of quantum entanglement is one of the fastest processes in nature. Scientists show that using special tricks, this can be investigated on an attosecond scale. Scientists have managed to analyze ulrafast processes which up until now were considered to be 'instantaneous': When a laser pulse hits an atom with two electrons, one electron may be ripped out of the atom, while the other electron stays close to the nucleus. These two electrons can become entangled in such a way that the point in time, at which the electron was ejected from the atom, becomes uncertain and depends on the state of the other electron.

A new data-driven technique, called fingerprint mass spectrometry, provides a method for measuring the mass of individual proteins using nanoscale devices.

A new system helps human fact-checkers validate the responses generated by a large language model. By speeding validation time by 20 percent, the system could improve manual verification and help users spot errors in AI models deployed in real-world situations.

Researchers are taking experimental navigation technology to the skies, pioneering a backup system to keep an airplane on course when it cannot rely on global positioning system satellites.

Developing edge-computing and AI capabilities from wearable sensors enhances their intelligence, critical for the AI of Things, and reduces power consumption by minimizing data exchange between sensory terminals and computing units. This enables wearable devices to process data locally, offering real-time processing, faster feedback, and decreased reliance on network connectivity and external devices, thereby enhancing efficiency, privacy, and responsiveness in applications like health monitoring, activity tracking, and smart wearable technology.

Developing edge-computing and AI capabilities from wearable sensors enhances their intelligence, critical for the AI of Things, and reduces power consumption by minimizing data exchange between sensory terminals and computing units. This enables wearable devices to process data locally, offering real-time processing, faster feedback, and decreased reliance on network connectivity and external devices, thereby enhancing efficiency, privacy, and responsiveness in applications like health monitoring, activity tracking, and smart wearable technology.