Latest news with #geophysics
Yahoo
4 hours ago
- Science
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Scientists discover 'ghost' plume in Earth's mantle that likely rerouted India as it crashed into Eurasia
When you buy through links on our articles, Future and its syndication partners may earn a commission. Scientists have discovered an ancient "ghost" plume lurking beneath Oman. The magma plume is trapped beneath a thick portion of Earth's crust and the upper part of the mantle, the planet's middle layer. As a result, the material can't rise to trigger volcanic activity at the surface. Researchers don't know if the plume ever sparked eruptions, but evidence suggests it shifted the trajectory of the Indian tectonic plate during its collision with Eurasia tens of millions of years ago, according to a new study. The plume sits beneath Oman's Salma Plateau (also spelled Salmah and Selma), which is up to 6,600 feet (2,000 meters) high, said study lead author Simone Pilia, a geophysicist and assistant professor at King Fahd University of Petroleum and Minerals in Saudi Arabia. The plateau likely formed because of the plume, although some scientists link the plateau's formation to the bending of Earth's crust created by the Makran subduction zone off the coasts of Pakistan and Iran, Pilia told Live Science. "A plume is hot material that wants to rise, rise, rise — so it's underneath and it's pushing up, creating topography," Pilia said. "The uplift [at the Salma Plateau] is rather small, but it's still there. It's telling you that the plume is active." Researchers discovered the plume thanks to seismic waves, or sound waves that travel through Earth at different speeds depending on the chemical makeup of the material. Oman has a dense network of stations that record seismic data, which made the research possible, Pilia said. He named the plume "Dani" after his son. Related: Africa is being torn apart by a 'superplume' of hot rock from deep within Earth, study suggests The Dani plume is the first clear example of an amagmatic "ghost" plume — a term the study authors coined to describe mantle plumes that don't trigger volcanic activity. Mantle plumes originate from the core-mantle boundary roughly 1,800 miles (2,900 kilometers) beneath Earth's surface. These plumes typically fuel volcanic eruptions because they undergo a process called decompression melting as they rise through the mantle and crust. Many mantle plumes trigger volcanic eruptions in the middle of oceanic plates, including in Hawaii, Pilia said. But mantle plumes rarely trigger eruptions within continental plates; they can't rise or undergo decompression melting because they continental plates a thicker crust and upper mantle than oceanic plates do. Researchers have generally assumed that the lack of volcanism from mantle plumes in continental plates means that there are no mantle plumes beneath continental plates, Pilia said. But "absence of evidence is not evidence of absence," he said. "If you don't have surface volcanism, it doesn't mean that you don't have a plume." The Dani plume is proof that mantle plumes can exist without volcanic activity. "What we strongly believe is that there are many other ghost plumes that we don't know of," Pilia said. Africa is a good candidate for ghost plumes because it sits above one of Earth's two large low-shear-velocity provinces — continent-size blobs that protrude from the core-mantle boundary and feed plumes. Like Oman, Africa has regions with a very thick crust and upper mantle, so any plumes would be prevented from rising to the surface, Pilia said. "What we strongly believe is that there are many other ghost plumes that we don't know of." The Salma Plateau is around 40 million years old, which means the Dani plume is at least as ancient, according to the study, which was published online June 6 in the journal Earth and Planetary Science Letters. This timing coincides with the collision between the Indian and Eurasian plates — and this got the researchers thinking, Pilia said. The collision happened relatively close to what is now Oman, before the two plates moved northward to their current positions. Pilia and his colleagues reconstructed the trajectory of the Indian plate and found that it changed direction slightly between 40 million and 25 million years ago. RELATED STORIES —Scientists discover 'sunken worlds' hidden deep within Earth's mantle that shouldn't be there —Gargantuan waves in Earth's mantle may make continents rise, new study finds —North America is 'dripping' down into Earth's mantle, scientists discover "We made some other calculations and basically demonstrated that the shear stress produced by the plume was the reason for the change in azimuth [angle] of the Indian plate," Pilia explained. Researchers already knew that plumes can redirect tectonic plates — but until now, without knowledge of the Dani plume, they hadn't tied this shift in trajectory to a specific plume. Tectonic plates move, but plumes tend to stay in place, Pilia said. This means that scientists can sometimes trace the evolution of a plume through evidence left on tectonic plates as they move over the plume. However, in the case of the Dani plume, this evidence has been swallowed and erased by the Makran subduction zone, Pilia said. "That evidence is gone forever."
Sustainability Times
3 days ago
- Science
- Sustainability Times
'Physics Broken in Antarctica': Mysterious Signal from Ice Baffles Scientists and Defies All Known Particle Laws
IN A NUTSHELL 🔍 ANITA experiment detected surprising signals suggesting particles traveling through the Earth in unexpected ways. detected surprising signals suggesting particles traveling through the Earth in unexpected ways. ❌ Neutrinos ruled out as the source of these anomalies due to the steep angles of the detected signals. as the source of these anomalies due to the steep angles of the detected signals. 🧪 Other major detectors, like IceCube and the Pierre Auger Observatory , found no matching evidence, adding to the mystery. and the , found no matching evidence, adding to the mystery. 🚀 A next-generation detector, PUEO, is being developed to further investigate these unexplained emissions. In the realm of particle physics, where established theories largely dictate expectations, the unexpected discovery made by the Antarctic Impulsive Transient Antenna (ANITA) experiment has sent ripples through the scientific community. ANITA, a cosmic ray detector, has picked up perplexing signals that challenge conventional understanding. These signals, recorded at steep upward angles, suggest particles have traversed the Earth in ways previously deemed impossible. As researchers delve deeper, the possibility of unknown particles or new interactions among known particles emerges, inviting a re-examination of established scientific beliefs. ANITA's Groundbreaking Discovery The Antarctic Impulsive Transient Antenna (ANITA) is a balloon-borne experiment designed specifically to detect radio waves from cosmic rays interacting with Antarctic ice. Positioned approximately 25 miles above the icy surface, ANITA has a unique vantage point that allows it to listen for emissions produced by high-energy cosmic particles. The expectation is straightforward: detect neutrinos, the most elusive subatomic particles, as they interact with the ice. However, what ANITA detected defied these expectations. The signals appeared to rise through the Earth, a phenomenon that should not occur based on current particle physics models. Signals detected at angles as steep as 30 degrees below the horizon suggest these particles traveled through thousands of miles of solid rock before emerging from the ice. Such an occurrence challenges the very foundation of existing particle theories, raising the question of whether unknown forces are at play. 'Confirmed for the First Time': Scientists Turn Light Into a Never-Before-Seen Solid With Reality-Bending Quantum Properties Neutrinos Ruled Out as Source of Anomaly Neutrinos, nearly massless and chargeless particles, are known for their elusive nature. They pass through the universe, Earth, and even human bodies without much interaction. While they offer insights into cosmic events when detected, the ANITA signals did not behave like typical neutrino emissions. Stephanie Wissel from Penn State, who is part of the research team, noted that the detection of such signals from angles so steep suggests that these are not neutrinos. Wissel explained that neutrinos should not be able to travel through the Earth's crust without interacting. The fact that the signals were detected at all, given their steep angle, rules out neutrinos as the likely source. The scientific community is left grappling with these unexplained anomalies, as the math and physics behind the signals remain unfathomable under current models. 'Water Found Beyond Earth': Scientists Confirm It Formed Moments After the Big Bang in a Stunning Cosmic Revelation Other Detectors Found No Matching Evidence In an effort to corroborate ANITA's findings, researchers compared the data with results from other major neutrino detectors, such as IceCube in Antarctica and the Pierre Auger Observatory in Argentina. Unfortunately, neither of these experiments recorded signals similar to those captured by ANITA. This lack of supporting evidence adds to the intrigue, as it rules out most known particle sources. Extensive simulations and modeling were conducted to eliminate the possibility of background noise or known cosmic-ray signatures skewing the results. Yet, the signals remain anomalous, suggesting the presence of phenomena not accounted for by current scientific understanding. This situation has propelled researchers to consider the possibility of undiscovered particles or interactions. 'This Thing Shouldn't Exist': Scientists Stunned as Humanity Witnesses This Deep-Sea Monster Alive for the First Time Ever Next-Gen Detector May Solve the Mystery Looking to the future, Stephanie Wissel and her colleagues are developing a next-generation detector, known as PUEO, which promises to offer enhanced sensitivity and a better chance of identifying the source of these unusual emissions. With hopes that PUEO will detect more of these signals, researchers anticipate gaining insights into whether these anomalies indicate new physics or are simply rare environmental effects. Wissel remains hopeful that future flights will provide clarity. As she speculates that some interesting radio propagation effects might occur near ice and horizons, the scientific community eagerly awaits new data. The findings of this study, published in Physical Review Letters, underscore the importance of continually questioning established knowledge and pushing the boundaries of what is known. The mysterious signals detected by ANITA have opened the door to a realm of possibilities in particle physics, challenging established theories and inviting speculation about the unknown. As researchers prepare for future experiments with advanced detectors like PUEO, the scientific community stands on the brink of potential breakthroughs. Will these anomalies lead to a revolutionary understanding of particle physics, or will they simply reveal previously unconsidered environmental phenomena? The quest for answers continues. What groundbreaking discoveries might the next flight uncover, and how will they reshape our understanding of the universe? Our author used artificial intelligence to enhance this article. Did you like it? 4.3/5 (26)
The Sun
5 days ago
- Science
- The Sun
‘Mystery pulse' spotted 25 miles ABOVE Antarctica is ‘unknown to science' as baffled experts say they ‘don't understand'
STRANGE radio pulses detected roughly 25 miles (40km) above Antarctica could be the mark of a new cosmic particle, according to a new study. This rare signal was first detected by the Antarctic Impulsive Transient Antenna (ANITA) in 2006, a series of tools floating over icy continent carried by balloons. 3 The now-retired ANITA experiment aimed to detect ultra-high-energy (UHE) cosmic neutrinos - or "ghost particles" - and other cosmic rays as they rain down on Earth from space. While ANITA usually picks up cosmic signals that bounce off the ice, this new radio pulse came from beneath the horizon and under the ice sheet. Its orientation cannot currently be explained by particle physics, a study in the journal Physical Review Letters wrote. A similar event was recorded in 2014, and it has continued to baffle scientists. The mysterious radio waves were being emitted at a steep angle below the ice, suggesting they had to pass through thousands of miles of rock before reaching ANITA. All those obstacles would typically leave a radio pulse too faint to be detectable - but not this signal. "It's an interesting problem, because we still don't actually have an explanation for what those anomalies are," ANITA team member and Penn State University researcher Stephanie Wissel said in a statement. "What we do know is that they're most likely not representing neutrinos." Scientists have ruled out neutrinos, the most common particle in the universe. Neutrinos are unofficially known as "ghost particles" due to the fact that they don't have any mass or carry any charge. "You have a billion neutrinos passing through your thumbnail at any moment, but neutrinos don't really interact," added Wissel. "So, this is the double-edged sword problem. If we detect them, it means they have traveled all this way without interacting with anything else. "We could be detecting a neutrino coming from the edge of the observable Universe." Scientists suspected that a supernova erupting in space could have coughed a slew of neutrinos in Earth's direction. An international team of researchers attempting to solve the mystery conducted a series of simulations to see if the 2006 and 2014 events align with any significant cosmic events, with data from the the Pierre Auger Observatory in Argentina. There was a supernova that aligned with the signals captured in 2014, but not the 2006 event. So there is no clear indication that this cosmic event is what caused the bizarre radio waves. What scientists have done, however, is narrow down their set of explanations. "My guess is that some interesting radio propagation effect occurs near ice and also near the horizon that I don't fully understand, but we certainly explored several of those, and we haven't been able to find any of those yet either," said Wissel. "So, right now, it's one of these long-standing mysteries, and I'm excited that when we fly [Payload for Ultrahigh Energy Observations], we'll have better sensitivity. "In principle, we should pick up more anomalies, and maybe we'll actually understand what they are. "We also might detect neutrinos, which would in some ways be a lot more exciting." 3
Yahoo
5 days ago
- Science
- Yahoo
Mysterious radio pulses detected high above Antarctica may be evidence of an exotic new particle, scientists say
When you buy through links on our articles, Future and its syndication partners may earn a commission. A cosmic particle detector has spotted a burst of strange radio signals from the ice of Antarctica that currently defy explanation. The results could hint at the existence of new particles, or interactions between particles currently unknown to physics, scientists say. The mystery radio pulses were picked up about 25 miles (40 kilometers) above Earth by the Antarctic Impulsive Transient Antenna (ANITA) experiment. ANITA is a series of instruments that float over Antarctica, carried by balloons with the aim of detecting ultra-high-energy (UHE) cosmic neutrinos and other cosmic rays as they pelt Earth from space. ANITA usually picks up signals when they are reflected off the ice of Antarctica, but these pulses were different, coming from below the horizon at an orientation that currently can't be explained by particle physics. "It's an interesting problem, because we still don't actually have an explanation for what those anomalies are," ANITA team member and Penn State University researcher Stephanie Wissel said in a statement. "What we do know is that they're most likely not representing neutrinos." The radio waves detected by ANITA were oriented at very steep angles, 30 degrees below the surface of the ice. This means that the signal had to pass through thousands of miles of rock before reaching ANITA. This should have led to interactions that left the radio pulses too faint to be detectable, but clearly that didn't happen here. The immediately obvious suspect for this signal is neutrinos. After all, it is the signature of these particles that ANITA is designed to pick up. Neutrinos are unofficially known as "ghost particles" due to the fact that they carry no charge and are virtually massless. Thus, as neutrinos — also the most abundant particles in the universe — stream through the cosmos at near-light speeds after being launched by powerful cosmic events, they can "phase" through matter, barely interacting. That means they remain unchanged after traversing many light-years, making them incredible "messengers" that can teach scientists about the events that launched them. However, this ghostly nature also makes neutrinos incredibly tough to detect. "You have a billion neutrinos passing through your thumbnail at any moment, but neutrinos don't really interact," Wissel said. "So, this is the double-edged sword problem. If we detect them, it means they have traveled all this way without interacting with anything else. We could be detecting a neutrino coming from the edge of the observable universe." Fortunately, even catching one neutrino as it passes through Earth can reveal a wealth of information. So, designing sophisticated experiments and taking them to remote regions of Earth or placing them deep underground in the hope of busting a cosmic ghost is well worth the effort for scientists like Wissel. "We use radio detectors to try to build really, really large neutrino telescopes so that we can go after a pretty low expected event rate," Wissel said. Just such an instrument, ANITA floats 25 miles over the ice of Antarctica, away from the possibility of other interfering signals, hunting for so-called "ice showers." "We point our antennas down at the ice and look for neutrinos that interact in the ice, producing radio emissions that we can then sense on our detectors," Wissel continued. These ice showers are caused by a particular "flavor" of neutrino called tau neutrinos, which strike the ice and interact to create a daughter particle called a tau lepton. This rapidly decays into an "air shower" containing even smaller constituent particles. Distinguishing between air showers and ice showers reveals the characteristics of the initial interacting particle and the origin of this particle. Wissel compares the strategy to using the angle of a bounced ball to trace it back to its initial path. However, because the angle of these newly detected signals is sharper than current models of physics allow, the backtracking process isn't possible in this case. Even more confusingly, other neutrino detectors like the IceCube Experiment and the Pierre Auger Observatory didn't detect anything that could explain these signals and the upward-oriented air shower. Thus, the ANITA researchers have declared the signals as "anomalous," determining they weren't the result of neutrinos. The signals could therefore be indicative of something new, perhaps even a hint of dark matter, the mysterious cosmic "stuff" that accounts for around 85% of the universe's matter content. Related Stories: — Scientists detect highest-energy ghost particle ever seen — where did it come from? — Elusive neutrinos caught streaming from a black hole hidden in dust — The greatest astronomical discoveries of the past 25 years Further answers may have to wait for the "next big thing" in neutrino detection, the larger and more sensitive Payload for Ultrahigh Energy Observations (PUEO) instrument, currently being developed by Penn State. "My guess is that some interesting radio propagation effect occurs near ice and also near the horizon that I don't fully understand, but we certainly explored several of those, and we haven't been able to find any of those yet either,' Wissel said. "So, right now, it's one of these long-standing mysteries, and I'm excited that when we fly PUEO, we'll have better sensitivity. "In principle, we should pick up more anomalies, and maybe we'll actually understand what they are. We also might detect neutrinos, which would in some ways be a lot more exciting."The team's research was published online in March in the journal Physical Review Letters.
Gizmodo
6 days ago
- Science
- Gizmodo
Scientists in Antarctica Detect Deep-Earth Signals That Defy Known Physics
A balloon-borne experiment over Antarctica, designed to detect cosmic radio waves, has instead picked up bizarre signals that appear to be coming from deep within the ice. These signals challenge our current understanding of particle physics, scientists say. The Antarctic Impulsive Transient Antenna (ANITA) experiment consists of radio antennas flown on NASA balloons 19 to 24 miles (30 to 39 kilometers) over the surface of Antarctica. In recent years, the detector has recorded radio pulses that seemed to rise up through the Earth. ANITA detected these signals at 'really steep angles, like 30 degrees below the surface of the ice,' co-author Stephanie Wissel, an associate professor of physics at Penn State, said in a university statement. This suggests that the radio pulses traveled up through 6,000 to 7,000 kilometers (3,700 to 4,300 miles) of solid rock to reach the detector—which shouldn't be possible. According to current models of particle physics, these radio pulses should have been completely absorbed by the rock, making detection impossible. 'It's an interesting problem because we still don't actually have an explanation for what those anomalies are,' Wissel said. She and her colleagues published their findings in the journal Physical Review Letters in March. ANITA's overarching goal is to gather information about deep space events by analyzing signals that reach Earth. This experiment plays a pivotal role in the search for neutrinos—elusive particles with no charge and the smallest mass of all subatomic particles. Neutrinos are abundant throughout the universe—they're constantly passing through us—and they usually come from high-energy sources like the Sun or supernovae. The problem is that their signals are very difficult to detect, according to Wissel. ANITA aims to overcome this challenge by sniffing out the radio emissions neutrinos emit when they interact with Antarctic ice. As the balloon-borne detector flies over stretches of ice, it looks for 'ice showers,' cascades of particles triggered by neutrinos hitting surface ice. These particle showers produce radio signals that ANITA can detect. Ice-interacting neutrinos also produce a secondary particle called a tau lepton that gradually breaks down and loses energy. This decay triggers another type of emission known as an 'air shower.' Researchers can distinguish between ice and air showers to characterize the particle that created the signal, then trace the signal back to its origin. But the unusually sharp angle of the anomalous signals ruled out the possibility that they were coming from ice-interacting neutrinos or the tau leptons they produce. Wissel and her colleagues analyzed data from multiple ANITA flights and compared it to mathematical models and simulations of both cosmic rays and air showers. This allowed them to eliminate the possibility of ANITA detecting other known particle-based signals. Next, the researchers compared the ANITA data to findings from other major neutrino detectors such as the IceCube Experiment and the Pierre Auger Observatory to see if they had captured similar anomalies. They still didn't find an answer. The other detectors did not register anything that could explain ANITA's anomalies. The only thing Wissel and her colleagues can say for certain is that the particles causing the strange signals are not neutrinos. Hopefully, the next big detector will reveal more information about these anomalies. At Penn State, Wissel's team is designing and building the Payload for Ultrahigh Energy Observation (PUEO) mission. This new detector will be larger and better at detecting neutrino signals, according to Wissel. She's already forming an early hypothesis about the nature of these anomalies. 'My guess is that some interesting radio propagation effect occurs near ice and also near the horizon that I don't fully understand, but we certainly explored several of those, and we haven't been able to find any of those yet either,' Wissel said. 'So, right now, it's one of these long-standing mysteries, and I'm excited that when we fly PUEO, we'll have better sensitivity. In principle, we should pick up more anomalies, and maybe we'll actually understand what they are. We also might detect neutrinos, which would in some ways be a lot more exciting.'
