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Earth and the Solar System Could Have Formed from Exploding Nearby Stars

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SNR 0519, the remnants of a supernova that erupted around 600 years ago

Claude Coenen/ESA/Hubble & NASA

Our planet may owe some of its characteristics to a neighboring star that met its end as a supernova during the formation period of the solar system. This notion of a supernova bubble enveloping the sun and inundating it with cosmic rays might be a common phenomenon across the galaxy, implying that there could be many more Earth-like planets than we ever imagined.

Thanks to ancient data, we understand from a meteorite sample that the early solar system was rich in radioactive materials that generated significant heat and quickly decayed. The heat produced by these elements was crucial for releasing substantial amounts of water from the colliding space rocks and comets that coalesced to form Earth, ensuring there was enough water for life to eventually thrive.

However, the origin of these elements remains a mystery. While many are commonly produced in supernovae, simulations of nearby supernovae have faced challenges in replicating the exact ratios of radioactive elements observed in meteorite specimens from the early Solar System. A significant issue is that these explosive events were incredibly forceful and might have obliterated the delicate early solar system before planetary formation could take place.

Recently, Ryo Sawada and fellow researchers at the University of Tokyo have discovered that if a supernova occurs at an adequate distance, it could supply Earth with the necessary radioactive components without interfering with the planet-forming process.

In their theoretical framework, a supernova located approximately three light-years from our solar system could initiate a two-step process to generate the essential radioactive elements. Certain radioactive substances, like aluminum and manganese, are directly created during supernova explosions and might reach the solar system propelled by shock waves from the explosion.

Subsequently, the high-energy particles known as cosmic rays released by the supernova travel along these shock waves, colliding with other atoms in the gaseous, dusty, and rocky disk still in its formative phase, birthing the remaining radioactive elements such as beryllium and calcium. “We realized that prior models of solar system formation primarily concentrated on the injection of matter, neglecting the role of high-energy particles,” stated Sawada. “We contemplated, ‘What if our nascent solar system was simply engulfed in this particle bath?'”

Due to the occurrence of this process in more distant supernovae than previously explored, Sawada and his team estimate that between 10 and 50 percent of Sun-like stars and planetary systems might have been enriched with radioactive elements in this manner, leading to the formation of water-abundant planets that resemble Earth. Earlier theories posited that the proximity of the supernova would have made such an event exceedingly rare, akin to “winning the lottery,” as Sawada described. The fact that the supernova is further positioned indicates that “Earth’s creation is probably not an unusual occurrence, but a widespread phenomenon that transpires throughout the galaxy,” he adds.

“This is exceedingly clever because it strikes a harmonious balance between destruction and creation,” remarks Cosimo Insera from Cardiff University in the UK. “The right elements and the correct distance are essential.”

If this theory holds true, Inserra mentioned that upcoming telescopes like NASA’s Habitable World Observatory could significantly aid in the search for Earth-like planets by identifying remnants of ancient supernovae and locating systems that were within proximity to supernovae during their formation stages.

Scientific Progress DOI: 10.1126/sciadv.adx7892

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Source: www.newscientist.com

Researchers Discover That “Linear Dune Canyons” on Mars Were Formed by Sliding Carbon Dioxide Ice Blocks

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Parallel channels known as linear dune canyons can be observed within some of Mars’ dunes. Contrary to what their name suggests, these canyons are frequently quite winding. It was previously believed that these landforms were created through debris flow processes influenced by liquid water. However, recent satellite imagery has revealed that they are active during the local spring due to processes involving carbon dioxide ice. During the Martian winter, ice accumulates on the dunes, breaking off at the top as temperatures rise in early spring. In new experiments conducted in the Mars Chamber, planetary researchers from Utrecht University, the University of Le Mans, the University of Nantes, the Grenoble Institute of Astrophysics, and the Open University have demonstrated that linear dune canyons form when blocks of carbon dioxide and ice slide or submerge into the sandy slopes of dunes, or shift downwards with considerable force, draining the nearby sand. This drilling action is triggered by a powerful gas flow generated by the sublimation of carbon dioxide ice, as it transitions into carbon dioxide gas. The movement of sliding carbon dioxide ice blocks contributes to the formation of shallow channels, while the excavation of carbon dioxide ice results in the development of deep, winding channels in Martian dunes.

Two examples of Martian dunes with linear dune gullies: (a) linear dune gullies in the dune field of Gall Crater; (b) A linear dune canyon in the dune field of an unnamed crater in the center of the Hellas Plain. Image credit: Roelofs et al., doi:10.1029/2024GL112860.

Linear dune canyons are remarkable and enigmatic formations located in the mid-latitude sand dune regions of Mars.

Despite their designation, these parallel and often meandering waterways, characterized by sharp bends, limited source areas, distinct banks, and hole-like channel terminations, have no equivalent on Earth.

They differ significantly from the conventional canyon topography found on steep slopes both on Mars and Earth, which typically features erosional alcoves, channels, and sedimentary aprons that are often larger than linear dune canyons.

“In our simulations, we observed how high gas pressures cause the sand to shift in all directions around the blocks,” stated Loneke Roelofs, a researcher at Utrecht University and lead author of the study.

“Consequently, the blocks become lodged into the slope and get trapped within cavities, surrounded by small ridges of settled sand.”

“However, the sublimation process persists, leading to continued sand displacement in all directions.”

“This phenomenon drives the block to gradually descend, resulting in a long, deep canyon flanked by small sand ridges on either side.”

“This is precisely the kind of canyon we find on Mars.”

In their research, Dr. Roelofs and colleagues merged laboratory experiments that let blocks of carbon dioxide and ice slide down sandy slopes under Martian atmospheric pressure with observations of the linear dune canyons located within the Russell Crater Giant Dunes.

“We experimented by simulating dune slopes of varying steepness.”

“We released chunks of carbon dioxide ice down a slope and observed the outcomes.”

“Once we discovered an appropriate slope, we began to see significant effects. The carbon dioxide ice chunks started to penetrate the slope and move downwards, resembling burrowing moles or dune sandworms. It was quite an unusual sight.”

“But how exactly do these ice blocks originate? They form in the desert dunes located in the midlands of Mars’ southern hemisphere.”

“During winter, a layer of carbon dioxide ice develops across the entire surface of the dunes, reaching thicknesses of up to 70 cm. As spring arrives, this ice begins to warm and sublimate.”

“The last remnants of the ice persist on the shaded side of the dune’s summit, where blocks will break off once temperatures rise sufficiently.”

“When a block reaches the base of the slope and halts its movement, sublimation continues until all carbon dioxide evaporates, leaving behind a cavity filled with sand at the dune’s base.”

This study was published in the October 8th issue of Geophysical Research Letters.

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Loneke Roelofs et al. 2025. Particle transport driven by explosive sublimation causes blocks of CO2 to slide and burrow, forming winding “linear dune valleys” in Martian dunes. Geophysical Research Letters 52 (19): e2024GL112860; doi: 10.1029/2024GL112860

Source: www.sci.news

Planetary Scientists Discover Seasonal Ozone Layers Formed by Mars’s Arctic Vortex

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Polar water is generated during the Martian season, which occurs due to the planet’s axis being tilted at an angle of 25.2 degrees, as explained by Dr. Kevin Olsen from Oxford and his colleagues at Latmos, CNRS, CNRS, Space Research Institute, Open University, and NASA.

This perspective view of Mars’ Arctic Ice Cap showcases its unique dark troughs arranged in a spiral pattern. The image is derived from observations made by ESA’s Mars Express, utilizing elevation data from NASA’s Mars Global Surveyor’s Mars Orbiter Laser Altimeter. Image credit: ESA/DLR/FU Berlin/NASA/MGS/MOLA Science team.

“The polar vortex’s atmosphere, extending from near the surface to around 30 km high, experiences extremely low temperatures, approximately 40 degrees Celsius lower than the surrounding area,” stated Dr. Olsen.

“In such frigid conditions, most of the water vapor in the atmosphere freezes and accumulates in the ice cap, resulting in ozone formation within the vortex.”

Normally, ozone is destroyed by reacting with molecules generated when ultraviolet radiation decomposes water vapor.

However, once all water vapor is depleted, there are no reactive molecules left for ozone, allowing it to accumulate in the vortex.

“Ozone plays a crucial role for Mars. It is a reactive form of oxygen that indicates the pace of chemical reactions occurring in the atmosphere,” Olsen noted.

“By investigating the levels of ozone and their variances, we gain insight into how the atmosphere evolves over time and whether Mars once had a protective ozone layer similar to Earth.”

Slated for launch in 2028, ESA’s Rosalind Franklin Rover aims to uncover evidence of life that may have existed on Mars.

The possibility that Mars had a protective ozone layer, safeguarding its surface against harmful ultraviolet radiation from space, enhances the likelihood of ancient life-sustaining conditions on the planet billions of years ago.

Polar vortices are produced during the Martian season as a consequence of the axial tilt of 25.2 degrees.

Similar to Earth, an atmospheric vortex forms above Mars’ North Pole at the end of summer and persists through spring.

On Earth, polar vortices can destabilize, losing their structure and shifting southward, often bringing cold weather to mid-latitudes.

A similar phenomenon can occur with Mars’ polar water vortex, which provides an opportunity to explore its internal dynamics.

“Studying the Northern Pole’s winter on Mars presents challenges due to the absence of sunlight, akin to conditions on Earth,” Dr. Olsen explained.

“By analyzing the vortex, one can differentiate between observations made inside and outside it, providing insight into ongoing phenomena.”

The atmospheric chemical suite aboard ESA’s trace gas orbiter examines Mars’ atmosphere by capturing sunlight filtered through the planet’s limb while the sun is positioned behind it.

The specific wavelengths of absorbed sunlight reveal which molecules are present in the atmosphere and their altitudes above the surface.

Nonetheless, this method is ineffective during the complete winter darkness on Mars when the sun does not illuminate the Arctic region.

The only chance to observe the vortex is during moments when its circular shape is lost, but additional data is required to pinpoint when and where this occurs.

To enhance their research, the scientists utilized NASA’s Mars Reconnaissance Orbiter’s Mars Climate Sounder instrument, measuring temperature variations to gauge the vortex’s extent.

“We sought sudden drops in temperature, which indicate entry into the vortex,” Dr. Olsen noted.

“By comparing ACS observations with data from Mars’ climate sounders, we observed significant atmospheric differences within the vortex compared to the surrounding air.”

“This presents a fascinating opportunity to deepen our understanding of Mars’ atmospheric chemistry and how polar night conditions shift as ozone accumulates.”

The findings were presented at the EPSC-DPS2025 Joint Meeting in Helsinki, Finland, this month.

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K. Olsen et al. 2025. What’s happening in the Arctic Vortex of Mars? EPSC Abstract 18: EPSC-DPS2025-1438; doi: 10.5194/epsc-dps2025-1438

Source: www.sci.news

Mysterious Galaxy Patterns Might Have Been Formed by a Cosmic Bullet

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SEI 256196186

The lines of galaxies that emerged after the collision of the two dwarf galaxies, which tore gases from one another.

Keim et al./Decals

A curious dwarf galaxy may have originated from a bullet-like collision in the universe.

Michael Keim from Yale University and his team employed the Keck Observatory in Hawaii to examine the distinctive trails of 12 small dwarf galaxies located approximately 75 million light-years from the Milky Way.

The orientation and velocity of the galaxies indicate that they resulted from a head-on impact between two galaxies known as NGC 1052-DF2 and NGC 1052-DF4. This collision expelled gas, which eventually coalesced into a group of stars due to gravitational attraction.

“They’re exceptionally unique,” states Kayme. “This is the only known system of its kind.”

Keim and his colleagues named this system after a similar cluster of large galaxies referred to as Bullet Clusters.

It is believed that the two galaxies collided at a speed of 350 kilometers per second around 9 billion years ago. As they passed through one another, gas was stripped from each galaxy. “While it’s improbable for two stars to collide,” notes Kayme, “the same does not apply to gas clouds.”

Interestingly, the remnants of stars left after the collision appear to lack dark matter. This is quite unusual, as most galaxies contain a substantial amount of dark matter, often comprising over 90% of their total mass.

Keim and his team theorize that this anomaly may stem from dark matter’s inability to interact with regular matter during the gas stripping process or because it remained unaffected by the interaction.

This finding may challenge alternative theories regarding dark matter, which posit that discrepancies in stellar and galactic behavior stem from gravitational effects rather than the existence of dark matter particles. “This suggests that dark matter is indeed a particle that can be separated from a galaxy,” explains Kayme.

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Source: www.newscientist.com

Water may have formed shortly after the Big Bang, study suggests

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Water was born as a result of an explosion star

PixelParticle/Getty Images

The first water molecules could have formed just 100 million to 200 million years after the Big Bang – even the first galaxy kicked off the processes that led to life on Earth.

Shortly after the Big Bang, most of the problems in the universe were hydrogen and helium, with only traces of other lighter elements, such as lithium. Heavy elements like oxygen are not yet present, and water is impossible to form.

These early elements were combined into the first star and produced heavier elements through oxygen-containing fusion. When these stars reach the end of their lives, they explode as supernovae, releasing these heavier elements, allowing oxygen to mix and mix with existing hydrogen to combine H.2O – Water.

Previous research It shows that even the relatively small amount of oxygen produced by the earliest stars could create water molecules, but they say up until now they have not simulated exactly what happens when a protostar becomes a supernova, and how the elements it released blended with the cosmic environment in which the stars were formed. Daniel Warren At the University of Portsmouth, UK. “To do anything less, you just don't know what's going on,” he says.

To investigate this, Whalen and his team used computer models to simulate the birth and death of the first star in a realistic context. These early stars are thought to range from 13 times the massive range of the Sun to 200 times the size of the Sun, so researchers modeled both extremes.

As you can imagine, the larger stars spit out more oxygen and produced more water in the form of steam clouds around the Jupiter mass, while the smaller stars produced Earth's mass, says Whaleen.

Depending on the mass of the star, researchers discovered that water took between 3 million and 90 million years after the supernova explosion. In other words, the first water molecules were formed 100-200 million years after the Big Bang.

Importantly, however, the team discovered that this water was not simply spreading throughout the universe. Instead, gravity caused it, and the other heavy elements produced by the first star were clumped together. That meant these chunks were breeding grounds for the second generation stars, and perhaps the first planet. “It was a huge result,” Whalen says.

“Even before the galaxy took place, this idea of ​​water forming essentially overturning decades of thought about the first emergence of life in the universe,” says Whalen. Team Members Muhammadratif At UAE University, researchers now say they will simulate whether water vapor can survive the destruction of the formation of the first galaxy and harsh radiation.

“We know that the chemistry of life we ​​know requires liquid water and can only be obtained in objects with surfaces in the universe or atmospheric.” avi loeb At Harvard University. It would have been a lot of time before this initial vapor condense into liquid water, but he says it could have helped them to find second-generation stars and their planets using instruments like the James Webbspace Telescope to help them understand this process more, and perhaps these planets could have been habitable millions of years after the Big Bang.

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Source: www.newscientist.com

New research suggests WASP-121B may have originally formed much closer to its parent star than previously thought.

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Astronomer using Immersed lattice infrared flash device (IGRINS) Gemini South Telescope devices looked at Wasp-121B, one of the most widely studied Ultra Hot Jupiter.

The artist's illustration indicates Wasp-121B, an alien world that has lost magnesium and iron gas from the atmosphere. Image credit: NASA / ESA / J. OLMSTED, STSCI.

WASP-121B, discovered by astronomers using Wasp-South Survece in 2016, is 1.87 times that of Jupiter, 1.18 times large.

The host star, WASP-121 (TYC 7630-352-1) is an active F6 main sequence star about 1.5 times the size of the sun.

The WASP-121 system is about 881 light-years away to the puppy constellation.

WASP-121B is a so-called “hot jupiter” and takes only 1 for three days to get on WASP-121 on track. As it is very close to the parent's star, as it approaches, the gravity of the star begins to tear.

Astronomers estimate that the temperature of the planet is about 2,500 degrees (Hana 4,600 degrees), which is enough to boil some metals.

The new Iglin observation results have revealed something unexpected about the WASP-121B formation history.

With these observations, Peter Smith and his colleagues at the Arizona State University, for the first time, measured the ratio of passenger rocks and ice using a single instrument.

“Gemini South using IGRINS has actually measured individual chemical existence more accurately than even achieving a space -based telescope,” said Smith.

The spectroscopic data indicates that the WASP-121B has a high ratio of rock and ice, and indicates that excessive rocky materials have been accumulated during the formation.

This suggests a planet formed in the area of ​​the protranetary disk that is too hot for the ice to condense.

“Our measurement means that this typical view must be reconsidered and the planetary formation model needs to be revisited,” Smith said.

Astronomers also discovered a remarkable feature of the WASP-121B atmosphere.

“The climate of this planet is extreme, not the earth's climate,” Smith said.

Since the planet daySide is very hot, elements that are generally considered “metal” evaporate in the atmosphere and can be detected by the spectroscopic method.

The strong wind blows these metals into the permanent night side of the planet. There, it is cool enough to condense and rain. This is an effect observed on Wasp-121B in the form of calcium rain.

“The sensitivity of our device can be used to examine the subtle wind speed by examining various areas, altitude, and long terms using these elements, revealing how dynamic this planet is. You can do it, “said Smith.

Survey results Will be displayed in Astronomy Journal。

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Peter CB Smith et al。 2025. Roasted marshmallow program with Gemini South Igulin. II. WASP-121 B has a ratio of superstar C/O and impact resistance and volatility. AJ 168, 293; DOI: 10.3847/1538-3881/AD8574

Source: www.sci.news

Researchers find the precise moment when humans and dogs formed a bond

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Just like iconic duos such as fish and chips, Batman and Robin, and Jack and Jill, humans and dogs have always been destined to be together. But when did this special bond first form? Scientists may have finally discovered the answer.

A recent study led by researchers from the University of Arizona delved into archaeological sites in Alaska, unveiling that the connection between humans and the ancient ancestors of dogs traces back as far as 12,000 years ago.

“This study provides evidence that humans and dogs shared a close relationship in the Americas earlier than previously thought,” stated the lead author of the study, François Lanoe, Assistant Professor in the Department of Anthropology at the University of Arizona. François Lanoe

Initial excavations in 2018 uncovered the lower leg bones of an adult dog dating back 12,000 years in Alaska, shedding light on the close relationship between humans and dogs during that era, especially with signs of possible domestication on the rise.

A more recent excavation in June 2023 unearthed an 8,100-year-old dog jawbone in the same region, providing further evidence of the early human-canid bond. Chemical analysis of the bones revealed evidence of a diet consisting of salmon, suggesting human involvement in the dog’s lifestyle.

While these findings hint at the earliest known relationship between humans and dogs, researchers remain cautious due to the age of the specimens and uncertainties regarding their genetic relation to modern dog populations.

As research continues to unfold, the team hopes to clarify the intricate history behind the companionship between humans and canids, ensuring they are on the right evolutionary path.

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Source: www.sciencefocus.com

After days of observation, scientists confirm a 650-foot-high tsunami formed in Greenland.

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  • Seismologists detected unusual vibrations and determined that a 650-foot-high tsunami had occurred in Greenland.
  • The tsunami was caused by melting glacial ice that triggered landslides and washed away water in Greenland's fjords.
  • The waves it created continued to travel back and forth across the fjord for nine days.

Last September, seismologists around the world detected vibrations never before observed.

The monotony seemed to come from Greenland and continued for nine days.

“We saw some very strange signals at some stations in the north that we'd never seen before,” said Karl Ebeling, a seismologist at the Scripps Institution of Oceanography at the University of California, San Diego.

Shortly after the vibrations began, a cruise ship sailing near a Greenland fjord noticed that a key landmark on the remote island of Ella, a scientific research and Danish military dog ​​sled patrol base, had been destroyed.

The event drew an international group of seismologists, the Danish military and oceanographers into the mystery: what struck the island, and where did it come from?

On Thursday, the researchers They published their findings in the journal Science.The island was hit by one of the largest tsunamis on record, leaving a scar about 650 feet high.

It was the result of a rare series of cascading events caused by climate change.

The researchers traced the initial trigger to the collapse of a glacier tongue that had been thinned by rising temperatures. This destabilized the steep mountainside, sending an avalanche of rock and ice into Greenland's deep Dikson Fjord. Massive amounts of water were displaced, causing towering waves to move across the narrow fjord, about a mile and a half wide.

The tsunami, at least as high as the Statue of Liberty, surged up the steep rock faces along the fjord and, because the landslide struck the waterway at a nearly 90-degree angle, sent waves circling the channel for nine days — a phenomenon scientists call a seiche.

“No one has ever seen anything like this,” said Christian Svennevig, lead author of the study and a geologist and senior research scientist at the Geological Survey of Denmark and Greenland.

The findings are the result of a complex year-long investigation. The team determined that Ella Island, about 45 miles from the landslide site, was hit by a tsunami at least 13 feet high.

Tourists visit the island from time to time.

“The cruise ship had been docked off the coast just a few days before,” Svennevig said. “We were really lucky that no one was there when it happened.”

The seiche was the longest scientists had ever observed: Until now, tsunamis generated by landslides have typically produced waves that dissipate within a few hours.

“This is really a cascade of events that has never been observed before,” said Alice Gabriel, co-author of the study. “The Earth is a very dynamic system, and we're currently at a stage where this very delicate balance is being disrupted pretty dramatically by climate change.”

Tsunamis triggered by landslides occur more frequently than many people realize and are a danger to people living and working in some Arctic and sub-Arctic regions.

In 2017, a landslide triggered a tsunami that killed four people and destroyed 11 homes. Attacked the village of Ngaatsiaq in West GreenlandThe tsunami was estimated to be at least 300 feet high. Two villages were abandoned in the aftermath of the tsunami due to fears of further landslides, and Svennevig said hundreds of people remain evacuated.

Bretwood “Higg” Higman, an Alaska geologist who studies landslide tsunamis but was not involved in the new study, said evidence suggests landslide tsunamis are a growing problem, but more research is needed.

“I'm pretty confident that these events are becoming more and more frequent,” he said. “Exactly how frequent these events are and can we predict the future? We're not there yet.”

Higman said he thought the Greenland study's researchers were “spot on” and that the research was an important example of how dangerous landslide-induced tsunamis could be.

The Arctic and sub-Arctic regions are warming two to three times faster than the rest of the Earth. As the ice melts, the exposed, dark surface absorbs more sunlight. Warming is triggering three dynamics that could make landslides more frequent in glacial regions, Higman said.

First, rising temperatures are eroding the permafrost within rock formations, weakening slopes and making them more susceptible to collapse. Second, warming is thinning the glaciers that support the rock slopes. Without the ice, sudden collapses could occur. Third, climate change is increasing the likelihood of heavy rains, which are the biggest risk factor for landslides because saturated rocks and soils become more slippery.

Higman has compiled a list of Alaska's slopes that are at risk for landslides that could trigger tsunamis. He said there are dozens of sites of concern that need further study, some of which are near populated areas where a landslide could be catastrophic.

“We're in an awkward position: Scientists know something, but they don't know enough to provide certainty to take action,” Higman said.

Last month, the U.S. Geological Survey reported a 56-foot-high landslide tsunami in Alaska's Pedersen Lagoon. Higman visited the site and believes the tsunami was larger than initially predicted.

Globally, risks are growing due to expanding development in some polar regions and increased visitation by miners, shippers and tourists, Svennevig said.

“At the same time as the population increases, the risk of landslides, geological hazards also increases,” he said. “It's an unfortunate combination.”

Source: www.nbcnews.com

Fresh study challenges commonly accepted ideas of how continents are formed

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In the new study, Dr David Hernández Uribe from the University of Illinois at Chicago used computer models to study the formation of magma, which is thought to hold clues to the origin of Earth's continents.

Hadean Earth. Image by Alec Brenner.

Magma is molten material that forms rocks and minerals as it cools.

Dr Hernández Uribe searched for magma that matched the compositional characteristics of rare mineral deposits called zircons, which date back to the Archean Era (2.5 to 4 billion years ago), when scientists believe the continents first formed.

In a recent study, researchers argued that Archean zircons could only have been formed by subduction, i.e. two crustal plates colliding under the ocean and pushing land up onto the surface.

This process still occurs today, causing earthquakes and volcanic eruptions and reshaping the coastlines of continents.

However, Dr. Hernández Uribe found that subduction was not necessary for the formation of Archean zircons.

Rather, he found that the minerals may have formed due to the high pressures and temperatures associated with the melting of Earth's thick primordial crust.

“Using my calculations and models, we can get the same characteristics in zircons and even a better match through partial melting at the base of the crust,” Dr Hernández Uribe said.

“So based on these results, we don't yet have enough evidence to say by what process the continents formed.”

The findings also create uncertainty about when plate tectonics began on Earth.

If Earth's first continents formed by subduction, then the continents would have started moving between 3.6 and 4 billion years ago, or just 500 million years after Earth existed.

But an alternative theory, that the first continents formed from melting crust, means that subduction and tectonic shifts may have started much later.

“As far as we know, Earth is the only planet in the solar system where plate tectonics is actively occurring,” Dr Hernández Uribe said.

“And this has implications for the origin of life, because how the first continents moved controlled the weather, controlled the chemistry of the oceans, and controlled everything related to life.”

of study Published in the journal on July 11, 2024 Nature Chemistry.

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Hernández-Uribe, D. Generation of Archean oxidized and wet magmas by mafic crustal overthickening. National GeographyPublished online July 11, 2024; doi: 10.1038/s41561-024-01489-z

This article is a version of a press release from the University of Illinois at Chicago.

Source: www.sci.news

New study suggests Milky Way’s thinner disk formed within one billion years of the Big Bang

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Use of Data ESA's Gaia mission Astronomers have discovered a number of metal-poor stars that are more than 13 billion years old and in orbits similar to our sun.

Rotational motion of a young (blue) and an older (red) star similar to the Sun (orange). Image credit: NASA / JPL-Caltech / R. Hurt / SSC / Caltech.

“The Milky Way has a large halo, a central bulge and bar, and thick and thin disks,” said Dr Samir Nepal of the Leibniz Institute for Astrophysics Potsdam and his colleagues.

“Most of the stars are found in a thin disk of the so-called Milky Way galaxy, which revolves regularly around the galactic center.”

“Middle-aged stars like our Sun, which is 4.6 billion years old, belong to a thin disk that is generally thought to have begun to form between 8 and 10 billion years ago.”

Astronomers used the new Gaia data set to study stars within about 3,200 light-years of the Sun.

They found a surprisingly large number of very old stars in the thin disk orbit, most of which are over 10 billion years old, with some being over 13 billion years old.

These ancient stars show a wide range of metal compositions: some are very metal-poor (as expected), while others have twice the metal content of the much younger Sun, indicating that rapid metal enrichment occurred early in the evolution of the Milky Way.

“These ancient stars in the disk suggest that the formation of the Milky Way's thin disk began much earlier than previously thought, around 4 to 5 billion years ago,” Dr Nepal said.

“This study also reveals that the Galaxy underwent intense star formation early on, leading to rapid metal enrichment in its inner regions and the formation of a disk.”

“This discovery brings the Milky Way's disk formation timeline into line with that of high-redshift galaxies observed with the NASA/ESA/CSA James Webb Space Telescope and the Atacama Large Millimeter Array (ALMA).”

“This shows that cold disks can form and stabilize very early in the history of the universe, providing new insights into the evolution of galaxies.”

“Our study suggests that the Milky Way's thin disk may have formed much earlier than previously thought and that its formation is closely linked to an early chemical enrichment in the innermost regions of the galaxy,” said Dr Cristina Chiappini, astronomer at the Leibniz Institute for Astrophysics Potsdam.

“The combination of data from different sources and the application of advanced machine learning techniques has allowed us to increase the number of stars with high-quality stellar parameters, which is an important step leading our team to these new insights.”

of paper will be published in journal Astronomy and Astrophysics.

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Samir Nepal others2024. Discovery of local counterparts of disk galaxies at z > 4: The oldest thin disk in the Milky Way using Gaia-RVS. A&Ain press; arXiv: 2402.00561

Source: www.sci.news

Microsoft Appoints DeepMind Co-founder to Lead Newly Formed AI Division

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Microsoft has named the co-founder of the British artificial intelligence research institute DeepMind as the head of its new AI division. Mustafa Suleiman, now 39 years old, co-founded DeepMind with Demis Hassabis and Shane Legg back in 2010. The company was later acquired by Google in 2014 for £400m and has since become the core of Google’s AI efforts. Suleiman left DeepMind in 2019 and will now lead Microsoft AI, a new organization focusing on the US company’s consumer products and research. Several members from Suleiman’s Inflection AI startup will also join the division.

Microsoft has made a multibillion-dollar investment in OpenAI, the developer of the ChatGPT chatbot, to develop generative AI technology. Satya Nadella, Microsoft’s CEO, praised Suleiman as a visionary product maker and a team leader with a bold mission. The new division will integrate Microsoft’s consumer AI efforts, such as the Copilot chatbot and the Bing browser, which utilizes ChatGPT technology. Copilot is a key element in Microsoft’s AI monetization efforts, enabling users to easily compose emails, summarize documents, create presentations, and more.

Suleiman’s colleague Karen Simonyan, also a co-founder of Inflection AI, will join the new division as a principal investigator. Meanwhile, Bloomberg News reported that Apple is in talks to incorporate Google’s Gemini AI product into the iPhone. Inflection AI, backed by Microsoft and Nvidia, has become one of the leading companies in the generative AI race.

Suleiman, who has roots in both Syria and the UK, recently published a book on AI titled “The Coming Wave.” In it, he discusses both the potential benefits and risks of AI technology, calling for an increase in research on AI safety. In an interview last year, he described the book as a “provocation,” noting the importance of predicting future trends and taking action to mitigate potential risks.

Source: www.theguardian.com

Global Coalition Formed by the US to Combat Foreign Government Disinformation and Cyber Warfare

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The US special envoy addressing the issue announced the formation of a global coalition of democracies to defend against disinformation campaigns by foreign governments.

James Rubin, special envoy for combating non-state propaganda and disinformation at the US Department of State’s Global Engagement Center (GEC), mentioned that the coalition aims to establish a clear understanding of information operations and the rights of other governments. He also highlighted the importance of reaching a consensus on defining common opinion even in moments of disagreement.

The US, UK, and Canada have already signed a formal framework agreement, and there are expectations of more countries joining the coalition. The GEC primarily focuses on countering disinformation campaigns by foreign powers and has been working towards developing a global strategy while uncovering covert disinformation operations, like Russia’s activities in Africa discrediting US health services.

A framework signed between the United States, United Kingdom, and Canada aims to counter foreign manipulation of states by addressing disinformation as a national security threat, requiring a coordinated response from governments and civil society. This emphasizes the need for a collective approach to enhance resilience and response to foreign intelligence threats through information sharing and collaborative data analysis tools.

James Rubin, a seasoned US government official and journalist, serving as a special envoy, acknowledged the complexity of the issue of disinformation and its intellectual challenges. He emphasized the importance of distinguishing between hostile opinion and disinformation to determine the appropriate government interventions.

James Rubin wants to promote more fact-based information. Photo: Tayfun Salcı/ZUMA Press Wire/REX/Shutterstock

He emphasized the need for fact-based information promotion while also finding ways to label information operations originating from foreign governments like China and Russia. He stressed the importance of identifying the sources of covert disinformation without censoring thoughts or opinions.

This challenging issue raises questions about the dynamics between the government and social media companies, particularly in countries like the United States with constitutional guarantees of free speech. In contrast, the European Union has taken more interventionist measures with laws regulating digital services and social media content.

Rubin underscored that it is essential to expose foreign disinformation operations without dictating social media companies’ behavior. He advocated for the enforcement of terms of service by these platforms in combatting disinformation efforts.

Addressing the asymmetry in information space access, Rubin highlighted the challenges posed by closed-off information environments of countries like Russia and China.

Source: www.theguardian.com

Hubble spots a group of newly formed stars at the end of a colliding galaxy

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Using the NASA/ESA Hubble Space Telescope, astronomers observed seven interacting galaxies with long tadpole-like tidal tails of gas, dust, and numerous stars. Hubble’s exquisite clarity and sensitivity to ultraviolet light led to the discovery of 425 clusters of newborn stars along these tidal tails. Each cluster contains up to a million newborn blue stars.

As seen in this Hubble image, galaxy AM 1054-325 has been distorted from its usual pancake-like spiral shape into an S-shape by the gravity of its neighboring galaxies. As a result, clusters of newborn stars form along tidal tails stretching across thousands of light years, resembling strings of pearls. Image credit: NASA/ESA/STScI/Jayanne English, University of Manitoba.

Tidal tail star clusters have been known for decades. When galaxies interact, gravitational tidal forces pull out long streams of gas and dust.

Two commonly used examples are antennas and rat galaxy It has elongated finger-like projections.

In a new study, astronomer Michael Rodrak of Randolph-Macon College and his colleagues combined new observational data with archival data to determine the age and mass of the tidal tail cluster.

Researchers discovered that these star clusters are very young, only 10 million years old.

And they appear to be forming at the same rate along a tail that extends over thousands of light years.

“It’s surprising that there are so many young objects in the tail,” said Dr Rodrak, lead author of the paper. paper Published in Royal Astronomical Society Monthly Notices.

“It tells us a lot about cluster formation efficiency.”

“With tidal tails, a new generation of stars will be built that otherwise would not exist.”

Tidal tails look like spiral arms of galaxies extending into space.

The outer part of the arm is pulled like taffy by the gravitational tug of war between a pair of interacting galaxies.

Before the merger occurred, galaxies may have been rich in dusty clouds of hydrogen molecules that simply remained inert.

However, during the encounter, the clouds swayed and clashed.

This compressed the hydrogen and triggered the firestorm of star birth.

“The fate of these strung star clusters is uncertain,” the astronomers said.

“They remain intact under gravity and can evolve into globular clusters that orbit outside the plane of the Milky Way.”

“Alternatively, they could disperse and form a stellar halo around their host galaxy, or be thrown off and become stars that wander between galaxies.”

“This pearly star formation may have been more common in the early Universe, when galaxies were colliding with each other more frequently.”

“These nearby galaxies observed by Hubble are proxies for what happened in the distant past, and are therefore laboratories for studying the distant past.”

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michael rodrak other. 2023. Star clusters in tidal dust. MNRAS 526 (2): 2341-2364; doi: 10.1093/mnras/stad2886

Source: www.sci.news