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How Two Massive Clumps of Superheated Material Influence Earth’s Magnetic Field

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Two colossal, ultra-hot rock formations, positioned 2,900 kilometers beneath the Earth’s surface in Africa and the Pacific Ocean, have influenced Earth’s magnetic field for millions of years, according to groundbreaking research led by Professor Andy Biggin from the University of Liverpool.

Giant superheated solid masses at the Earth’s mantle base impact the liquid outer core. Image credit: Biggin et al., doi: 10.1038/s41561-025-01910-1.

Measuring ancient magnetic fields and simulating their generation presents significant technical challenges.

To explore these deep Earth features, Professor Biggin and his team used paleomagnetic data in conjunction with advanced Earth Dynamo simulations. The flow of liquid iron in the outer core generates Earth’s magnetic field, akin to a wind turbine producing electricity.

Numerical models reconstructed critical insights about magnetic field behavior over the past 265 million years.

Even with supercomputers, conducting these long-term simulations poses enormous computational challenges.

The findings showed that temperature at the upper layer of the outer core is not uniform.

Instead, localized hot areas are accompanied by continent-sized rock structures exhibiting significant thermal contrasts.

Some regions of the magnetic field were found to remain relatively stable over hundreds of millions of years, while others displayed considerable changes over time.

“These results indicate pronounced temperature variations in the rocky mantle just above the core, suggesting that beneath hotter regions, liquid iron in the core may be stagnant, rather than flowing intensely as observed beneath colder areas,” Professor Biggin stated.

“Gaining such insights into the deep Earth over extensive timescales enhances the case for utilizing ancient magnetic records to comprehend both the dynamic evolution and stable properties of deep Earth.”

“These discoveries also bear significant implications for understanding ancient continents, including the formation and breakup of Pangea, and could help address long-standing uncertainties in ancient climate studies, paleontology, and natural resource formation.”

“It has been hypothesized that, on average, Earth’s magnetic field acts as a perfect bar magnet aligned with the planet’s rotation axis in these regions.”

“Our findings suggest that this may not be entirely accurate.”

This study is published in today’s edition of Nature Earth Science.

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AJ Biggin et al. Inhomogeneities in the mantle influenced Earth’s ancient magnetic field. Nature Earth Science published online on February 3, 2026. doi: 10.1038/s41561-025-01910-1

Source: www.sci.news

Explaining Mars’ one-sided magnetic field with the liquid inner core

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Recent measurements from NASA’s insight mission show that Mars’ core is less dense than previously believed planetary scientists. This shows that Mars has never developed a solid inner core at the earliest time in its history. in New research Published in the journal Geophysical Research BookResearchers at the University of Texas and elsewhere were hoping to understand the impact of this lack of a solid inner core.

Computer simulation of the unilateral magnetic field of early Mars. Image credits: Ankit Barik/Johns Hopkins University.

“Like Earth, Mars once had a strong magnetic field that protected the thick atmosphere from the solar wind,” said Dr. Chi Yang, a colleague at the University of Texas.

“But now only the magnetic imprint remains. But with a long, confused scientist, this imprint appears most strongly in the southern half of the red planet.”

The team’s new research will help explain the one-sided traces. We present evidence that the planet’s magnetic field covers only the southern half.

“The resulting biased magnetic field will match the traces we saw today,” Dr. Yang said.

“It will also make the Earth’s magnetic field that covers the entire Earth different from the Earth’s magnetic field.”

“If Mars’ inner core is liquid, a one-sided magnetic field can be generated.”

“The logic here is that it’s much easier to generate a hemispherical (one-sided) magnetic field because there is no solid inner core.”

“It could have influenced the ancient dynamos on Mars and perhaps could have maintained the atmosphere.”

In this study, researchers used computer simulations to model this scenario.

Until now, most early Mars studies relied on magnetic field models that gave the red planet an inner nucleus like Earth surrounded by solid, molten iron.

Scientists were urged to try to simulate a full liquid core after insights discovered that Mars’ core is made up of lighter than expected elements.

“That means there’s a very high chance that it’s melting because the core melts differently than Earth’s,” said Sabin Stanley, a professor at Johns Hopkins University.

“If Mars’ core was melting now, it would almost certainly have melted 4 billion years ago when it was known that Mars’ magnetic field was active.”

To test the idea, the author prepared an early Mars simulation with a liquid core and ran it dozens of times on a supercomputer.

With each run they made the northern half of the mantle planet a little hotter than the south.

Eventually, the temperature difference between the hotter mantle in the north and the colder mantle in the south began to escape from the core and only release at the southern tip of the planet.

The escape heat channeled in such a way was active enough to drive the dynamos and generate a powerful magnetic field focused on the Southern Hemisphere.

Planetary dynamos are self-supporting mechanisms that generate magnetic fields, usually through the movement of molten metal cores.

“We didn’t know if we’d explain the magnetic field, so it’s exciting to see that Mars’ interiors can create (single) hemispherical magnetic fields with an internal structure that fits insights as well as today,” Professor Stanley said.

This finding provides a compelling alternative theory for common assumptions that affect obliterating evidence of magnetic field elimination across rocky planets in the Northern Hemisphere.

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C. Yang et al. 2025. Mars hemispherical magnetic field from a full sphere dynamo. Geophysical Research Book 52(3): E2024GL113926; doi: 10.1029/2024GL113926

Source: www.sci.news

Using Earth’s Magnetic Field as a GPS, Migratory Birds Navigate Their Way

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Giant reed warbler migrating between Europe and Africa

AGAMI Photo Agency / Alamy Stock

Many migratory birds use the Earth's magnetic field as a compass, and others can use information from that field to more or less determine where they are on their mental map.

Greater Reed Warbler (Acrocephalus skillupaceus) appears to calculate geographic location by drawing data from various distances and angles between the magnetic field and the shape of the Earth. The study suggests that birds use magnetic information as a kind of “GPS,” telling them not only where to go, but also their initial whereabouts, they said. richard holland At Bangor University, UK.

“When we travel, we have a map that shows us where we are and a compass that shows us which direction to go to reach our destination,” he says. “We don't expect birds to have this much precision or knowledge about the entire planet. Yet, when they travel along their normal path, or even when they travel far from that path, they , and observe how the magnetic cues change.”

Scientists have known for decades that migratory birds rely on cues from the ocean. solar, star and earth's magnetic field To decide which direction to go. But using a compass to figure out direction and knowing where a bird is in the world are markedly different, and scientists are wondering if and how birds figure out their current map location. I'm still debating whether to do it or not.

Florian Packmore Germany's Lower Saxony Wadden Sea National Park Administration suspected that birds could detect detailed aspects of magnetic fields to determine their global location. Specifically, magnetic obliquity (the change in the angle of the Earth's surface relative to magnetic field lines) and magnetic declination (the difference in orientation between the geographic and magnetic poles) are used to better understand where you are in the world. He thought he might be able to do it.

To test their theory, Packmore, Holland and colleagues captured 21 adult reed warblers in Illmitz, Austria, on their migration route from Europe to Africa. So the researchers temporarily placed the birds in an outdoor aviary, where they used a Helmholtz coil to disrupt the magnetic field. They artificially altered the inclination and declination in a way that corresponded to the location of Neftekamsk, Russia, 2,600 kilometers away. “That's way off course for them,” Packmore says.

The researchers then placed the birds in special cages to study their migratory instincts and asked two independent researchers, who were unaware of changes in the magnetic field, to record which direction the birds headed. In the changed magnetic field conditions, most birds showed a clear tendency to fly west-southwest, as if trying to return to their migratory route from Russia. In contrast, when the magnetic field was unchanged, the same birds attempted to fly south-southeast from Austria.

This suggests that the birds believed they were no longer in Austria, but Russia, based solely on magnetic inclination and declination, Packmore said.

“Of course they don't know it's Russia, but it's too far north and east from where they should be,” Holland says. “And at that point, they look at their compass system and figure out how to fly south and west.”

However, the neurological mechanisms that allow birds to sense these aspects of the Earth's magnetic field are still not fully understood.

“This is an important step in understanding how the magnetic maps of songbirds, especially the great reed warbler, work,” he says. Nikita Chernetsov The professor at the Institute of Zoology of the Russian Academy of Sciences in St. Petersburg was not involved in the study.

The study confirms that the great reed warbler relies on these magnetic fields for positioning, but that doesn't mean all birds do, he added. “Not all birds work the same.”

Packmore and Holland said the birds were released two to three weeks after the study, at which point they were able to continue their normal migration. In fact, one of the birds they studied was captured a second time a year later. This means that the researchers' work did not interfere with the birds' successful migration.

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Source: www.newscientist.com

First Detailed Map of Solar Coronal Magnetic Field Created by Inouye Solar Telescope

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This groundbreaking achievement will improve our understanding of the Sun’s atmosphere and shed light on how its changing conditions affect our technology-dependent society.

The Inouye Solar Telescope has released the first map of the magnetic field signal in the solar corona measured using the Zeeman effect. Image courtesy of NSF/NSO/AURA/NASA’s Solar Dynamics Observatory.

The Earth’s magnetic field protects us from the solar wind, protects our atmosphere and makes life possible.

But electromagnetic fields and high-energy particles from extreme solar activity could disrupt satellites, power grids, and other systems necessary for an increasingly technological society.

Understanding these dynamic interactions, which change on timescales ranging from days to centuries, is crucial to safeguarding our infrastructure and current ways of life.

Measuring the magnetic properties of the Sun’s corona, or outer atmosphere, has long challenged astronomers and the limits of technology.

today, Daniel K. Inouye Solar TelescopeLocated near the summit of Haleakala on the Hawaiian island of Maui, the facility is a state-of-the-art facility designed to study coronas.

The satellite has produced the first and most detailed map of the coronal magnetic field to date, taking an important first step in solving these mysteries.

“Inoue’s achievements in mapping the Sun’s coronal magnetic field are a testament to the innovative design and capabilities of this pioneering and unique observatory,” said Dr. Tom Shad, NSF National Solar Observatory investigator.

“This groundbreaking discovery is expected to greatly improve our understanding of the Sun’s atmosphere and its impact on the solar system.”

The researchers used the Zeeman effect, which measures magnetic properties by observing the splitting of spectral lines, to create a detailed map of the magnetic field of the solar corona.

“Spectral lines are distinct lines that appear at particular wavelengths in the electromagnetic spectrum and represent light absorbed or emitted by atoms and molecules,” they explained.

“These lines are unique to each atom and molecule and act like a fingerprint. By looking at the spectrum, scientists can determine the chemical composition and physical properties of an object.”

“When exposed to a magnetic field like the Sun’s, these lines split apart, giving us insight into the magnetic properties of the object.”

Previous attempts to detect such signals, last reported 20 years ago, have lacked the detail and regularity needed for widespread scientific investigation.

Now, Inouye’s unparalleled capabilities make it possible to study these important signals in detail and on a regular basis.

The solar corona can usually only be seen during a total solar eclipse, when most of the Sun’s light is blocked and Earth’s sky becomes dark.

But the Inouye Telescope uses a technique called coronagraphy to create an artificial eclipse that allows it to detect extremely faint polarized signals, highlighting its unparalleled sensitivity and cementing its status as a unique window into viewing our home star.

This telescope is Cryogenic near-infrared spectropolarimeter (Cryo-NIRSP) is one of the telescope’s main instruments used to study the corona and map its magnetic field.

“Just as detailed maps of the Earth’s surface and atmosphere have improved the accuracy of weather forecasts, this remarkably complete map of the magnetic field of the Sun’s corona will help us more accurately predict solar storms and space weather,” said Dr. Carrie Black, program director for NSF’s National Solar Observatory.

“The invisible yet incredibly powerful forces captured in this map will continue to drive solar physics for the next century and beyond.”

“Mapping the strength of the corona’s magnetic field is a fundamental scientific advance not only for solar research but for astronomy in general,” said Dr. Christoph Keller, director of the National Solar Observatory.

“This marks the beginning of a new era in understanding how stars’ magnetic fields affect planets in our solar system and the thousands of exoplanetary systems currently known.”

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This article has been edited from an original release by the National Solar Observatory.

Source: www.sci.news

For the First Time, NASA’s Endurance Mission Measures Earth’s Bipolar Electric Field

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First hypothesized over 60 years ago Bipolar electric field Polar winds are the primary driver of a constant outflow of charged particles into space above the Earth’s poles. These electric fields lift charged particles in the upper atmosphere to higher altitudes than usual, and may have shaped the evolution of Earth in ways that are still unknown.

Collinson othersThey report that a potential drop of +0.55 ± 0.09 V exists between 250 km and 768 km due to the planetary electrostatic field, generated solely by the outward pressure of ionospheric electrons. They experimentally demonstrate that the Earth’s ambipolar field controls the structure of the polar ionosphere, increasing its scale height by 271%. Image courtesy of NASA.

Since the 1960s, spacecraft flying over Earth’s poles have detected streams of particles streaming from Earth’s atmosphere into space.

Theorists predicted these outflows, named them polar winds, and stimulated research to understand their causes.

Some outflow from the atmosphere was expected — intense, unobstructed sunlight should send some atmospheric particles escaping into space, like water vapor evaporating from a pot of water — but the observed polar winds were more puzzling.

Many of the particles inside were cold and showed no signs of heating, but they were moving at supersonic speeds.

“Something must be attracting these particles to the outer reaches of the atmosphere,” said Dr. Glynn Collinson, Endurance mission principal investigator and a researcher at NASA’s Goddard Space Flight Center.

The electric fields, hypothesized to be generated at subatomic levels, would be incredibly weak and their effects would be expected to be felt only for distances of hundreds of miles.

For decades, detecting it has been beyond the limits of existing technology.

In 2016, Dr Collinson and his colleagues began inventing a new instrument that they thought would be suitable for measuring Earth’s bipolar magnetic field.

The team’s equipment and ideas were perfectly suited for a suborbital rocket flight launched from the Arctic.

The researchers named the mission “Antarctic Expedition,” in honor of the ship that carried Ernest Shackleton on his famous 1914 Antarctic voyage. Endurance.

They set course for Svalbard, a Norwegian island just a few hundred miles from the North Pole and home to the world’s northernmost rocket launch site.

“Svalbard is the only rocket launch site in the world that can fly through the polar winds and make the measurements we need,” said Dr Susie Ingber, an astrophysicist at the University of Leicester.

Endurance was launched on May 11, 2022, reaching an altitude of 768.03 kilometers (477.23 miles) and splashing down in the Greenland Sea 19 minutes later.

Over the 518.2 kilometres (322 miles) altitude where Endurance collected data, it measured a change in electrical potential of just 0.55 volts (V).

“Half a volt is almost meaningless – it’s about the strength of a watch battery – but it’s just right for describing polar winds,” Dr Collinson said.

Hydrogen ions, the most abundant type of particle in the polar wind, experience an outward force from this field that is 10.6 times stronger than gravity.

“That’s more than enough to counter gravity, in fact to launch you into space at supersonic speeds,” said Dr. Alex Grosser, a research scientist at NASA’s Goddard Space Flight Center and Endurance project scientist.

Heavier particles are also accelerated: an oxygen ion at the same altitude, immersed in this 0.5 volt electric field, loses half its mass.

In general, scientists have found that bipolar magnetic fields increase what’s called the scale height of the ionosphere by 271%, meaning the ionosphere remains denser up to higher altitudes than it would be without the bipolar magnetic field.

“It’s like a conveyor belt that lifts the atmosphere up into space,” Dr Collinson said.

The Endurance discovery has opened up many new avenues of exploration.

The polarity field, as a fundamental energy field of the Earth alongside gravity and magnetism, may have continually shaped the evolution of the atmosphere in ways that we are only now beginning to explore.

Because it is generated by the internal dynamics of the atmosphere, similar electric fields are expected to exist on other planets, including Venus and Mars.

“Any planet with an atmosphere should have a bipolar magnetic field, and now that we’ve finally measured it we can start to learn how it has shaped our planet and other planets over time,” Dr Collinson said.

Team result Published in a journal Nature.

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G.A. Collinson others2024. Earth’s bipolar electrostatic field and its role in the escape of ions into space. Nature 632, 1021-1025;doi:10.1038/s41586-024-07480-3

This article is a version of a press release from NASA Goddard Space Flight Center.

Source: www.sci.news

Murchison Wide Field Array hunts for signs of alien technology beyond our galaxy

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Astronomers Murchison Widefield Alley Researchers in Western Australia conducted a search for extraterrestrial signals emanating from around 2,800 galaxies pointing towards the Vela supernova remnant with a spectral resolution of 10 kHz.

This diagram shows what a Kardashev Type III civilization might operate like. Containing stellar energy in so-called Dyson spheres is one way to harness the enormous energy on a galactic scale. The resulting waste heat products should be detectable with telescopes. Image by Danielle Futselaar / ASTRON.

“When we think about the search for extraterrestrial intelligence, we often consider the age and advancement of technology that could produce signals that we could detect with telescopes,” said Dr Chenoa Tremblay from the SETI Institute and Professor Steven Tingay from Curtin University.

“In popular culture, advanced civilizations are depicted as having interstellar spacecraft and the means to communicate.”

“In the 1960s, astrophysicist Nikolai Kardashev proposed a scale for quantifying the degree of technological advancement of extraterrestrial intelligence.”

“The Kardashev scale has three levels. A Type I civilization uses all the energy available on its planet (1016 W); Type II civilizations can consume stellar energy directly (1026 W) and a Type III civilization could consume all the energy emitted by the galaxy (1036 “W)”

“Civilizations at the higher end of the Kardashev scale could generate vast amounts of electromagnetic radiation detectable at galactic distances.”

“Some of the ideas that have been explored in the past have been to harness the light of stars in our galaxy, to colonize the solar system, and to use pulsars as a communications network.”

“Radio waves' ability to penetrate space over long distances and even planetary atmospheres makes them a practical tool for searching for interstellar communications.”

The authors used the Murchison Widefield Array (MWA), focusing on low radio frequencies (100 MHz), to look for signs of alien technology in galaxies beyond the Milky Way.

They observed about 2,800 galaxies in one observation, and determined the distances to 1,300 of them.

“This research represents a major step forward in efforts to detect signals from advanced extraterrestrial civilizations,” Dr Tremblay said.

“The MWA's wide field of view and low-frequency range make it an ideal tool for this type of study, and the limits we set will guide future research.”

of work Appeared in Astrophysical Journal.

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CD Tremblay & SJ Tingay. 2024. An extragalactic wide-field search for technosignatures with the Murchison Wide Field Array. ApJ 972, 76;doi:10.3847/1538-4357/ad6b11

Source: www.sci.news

Researchers Discover Oldest Evidence of Earth’s Magnetic Field in Greenland

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Recovering ancient records of the Earth's magnetic field is difficult because the magnetization of rocks is often reset by heating during burial due to tectonic movements over a long and complex geological history. Geoscientists from MIT and elsewhere have shown that rocks in West Greenland's Isua supercrustal zone have experienced three thermal events throughout their geological history. The first event was the most important, heating rocks to 550 degrees Celsius about 3.7 billion years ago. His two subsequent phenomena did not heat the region's northernmost rocks above 380 degrees Celsius. The authors use multiple lines of evidence to test this claim, including paleomagnetic field tests, metamorphic mineral assemblages across the region, and temperatures at which the radiometric ages of observed mineral assemblages are reset. They use this body of evidence to argue that an ancient record of Earth's magnetic field from 3.7 billion years ago may be preserved in the striated iron layer at the northernmost edge of the magnetic field. .

Earth's magnetic field lines. Image credit: NASA's Goddard Space Flight Center.

In a new study, Professor Claire Nicholls from the University of Oxford and colleagues examined a range of ancient iron-bearing rocks from Isua, Greenland.

Once locked in place during the crystallization process, iron particles effectively act as tiny magnets that can record both the strength and direction of a magnetic field.

Researchers found that 3.7 billion-year-old rocks exhibited magnetic field strengths of at least 15 microteslas, comparable to modern magnetic fields (30 microteslas).

These results provide the oldest estimates of the strength of Earth's magnetic field derived from whole rock samples, providing a more accurate and reliable estimate than previous studies using individual crystals.

“It's very difficult to extract reliable records from rocks this old, so it was really exciting to see the primary magnetic signals start to emerge when we analyzed these samples in the lab,” Professor Nichols said. said.

“This is a very important step forward in our efforts to understand the role of ancient magnetic fields in the creation of life on Earth.”

Although the strength of the magnetic field appears to remain relatively constant, the solar wind is known to have been significantly stronger in the past.

This suggests that surface protection from the solar wind may have strengthened over time, thereby allowing life to leave the protection of the oceans and migrate to the continents.

The Earth's magnetic field is created by the mixing of molten iron within a fluid outer core, driven by buoyancy as the inner core solidifies, forming a dynamo.

During the early stages of Earth's formation, a solid inner core had not yet formed, leaving unanswered questions about how the initial magnetic field was maintained.

These new results suggest that the mechanisms driving Earth's early dynamo were as efficient as the solidification processes that generate Earth's magnetic field today.

Understanding how the strength of Earth's magnetic field has changed over time is also key to determining when Earth's interior solid core began to form.

This helps us understand how fast heat is escaping from the Earth's deep interior, which is key to understanding processes such as plate tectonics.

A key challenge in reconstructing Earth's magnetic field back in time is that any event that heats rocks can change the preserved signal.

Rocks in the Earth's crust often have long and complex geological histories that erase information about previous magnetic fields.

However, the Isua supercrustal zone has a unique geology, sitting on a thick continental crust and protected from extensive tectonic movements and deformation.

This allowed scientists to build clear evidence for the existence of magnetic fields 3.7 billion years ago.

The results may also provide new insights into the role of magnetic fields in shaping the development of Earth's atmosphere as we know it, particularly regarding the release of gases into the atmosphere.

“In the future, we hope to expand our knowledge of Earth's magnetic field before oxygen increased in the Earth's atmosphere about 2.5 billion years ago by examining other ancient rock sequences in Canada, Australia, and South Africa. “We believe that this is the case,” the authors said.

“A better understanding of the strength and variability of ancient Earth's magnetic field will help determine whether the planet's magnetic field was important for harboring life on the planet's surface and its role in the evolution of the atmosphere. Masu.”

of study Published in Geophysical Research Journal.

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Claire IO Nichols other. 2024. Possible Archean record of geomagnetism preserved in the Isua supercrustal zone of southwestern Greenland. Geophysical Research Journal 129 (4): e2023JB027706; doi: 10.1029/2023JB027706

Source: www.sci.news

New image exposes magnetic field surrounding Milky Way’s black hole

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New and impressive images of the supermassive black hole located at the center of our galaxy show that its powerful magnetic field twists and rotates in a spiral pattern.

This is a never-before-seen view of Sagittarius A* (or Sgr A*), the massive black hole in the Milky Way galaxy that consumes nearby light and matter.

The images suggest similarities in structure between this black hole and the black hole in the galaxy M87. Although the black hole in M87, which was imaged for the first time, is over 1,000 times larger than Sagittarius A*, both exhibit strong, organized magnetic fields.

This pattern hints that many, if not all, black holes may share common traits, according to the scientists who published their findings in the Astrophysics Journal Letter on Wednesday.

“We’ve discovered that strong, orderly magnetic fields are crucial in how black holes interact with surrounding gas and matter,” said study co-leader and NASA Hubble Fellowship Program co-author, Einstein Fellow Sarah Isaun, as stated in a press release.

Isaun worked with an international team of astronomers known as the Event Horizon Telescope to conduct the research. This team comprises over 300 scientists from 80 institutions worldwide.

This same collaboration captured the first direct visual evidence of Sagittarius A* in 2022 and also studied the M87 galaxy, which is located approximately 53 million light-years away from Earth.

The magnetic field around the massive black hole at the center of the M87 galaxy, known as M87*, is believed to play a vital role in its extraordinary behavior. Black holes emit powerful jets of electrons and other subatomic particles into space at nearly the speed of light.

Although no such bursts of activity have been observed from Sagittarius A*, the similarities between the two black holes suggest that hidden jets may still be detected. Researchers suggest this possibility in the new images.


Source: www.nbcnews.com

The Event Horizon Telescope Detects a Twisted Magnetic Field Surrounding the Central Black Hole of the Milky Way

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According to astronomers’ best models of black hole evolution, the magnetic field within the accretion disk must be strong enough to push the accreted plasma out into the surroundings. New results from Sagittarius A*, the 4.3 million solar mass black hole at the center of the Milky Way galaxy, and its much larger cousin M87* provide the first direct observational evidence supporting these models.

This image from the Event Horizon Telescope shows a polarized view of Sagittarius A*. The lines superimposed on this image show the direction of polarization associated with the magnetic field around the black hole’s shadow. Image credit: EHT Collaboration.

In 2022, EHT collaboration The first image of Sagittarius A*, about 27,000 light-years from Earth, has been released, showing that the Milky Way’s supermassive black hole looks very good despite being more than 1/1000th smaller and lighter in mass than M87. revealed that they are similar.

This led scientists to wonder if the two men had more in common than just their looks. To find out, they decided to study Sagittarius A* in polarized light.

Previous studies of the light surrounding M87* revealed that the magnetic field around the supermassive black hole causes powerful jets of matter to be ejected into the surrounding environment.

Based on this study, new EHT images reveal that the same may be true for Sagittarius A*.

“What we’re seeing now is a strong, twisted, organized magnetic field near the black hole at the center of the Milky Way,” said astronomers at the Harvard University & Smithsonian Center for Astrophysics. said Dr. Sarah Isaun.

“In addition to having a polarization structure that is strikingly similar to that seen in the much larger and more powerful M87* black hole, Sagittarius A* has a polarization structure that is strikingly similar to that seen in the much larger and more powerful M87* black hole. We found that strong, well-ordered magnetic fields are important for how they act.”

Light is a vibrating or moving electromagnetic wave that allows us to see objects. Light can oscillate in a particular direction, which scientists call polarization.

Polarized light is all around us, but to the human eye it is indistinguishable from “normal” light.

In the plasma around these black holes, particles swirling around magnetic field lines impart a polarization pattern perpendicular to the magnetic field.

This will allow astronomers to see in clearer detail what’s happening in the black hole region and map its magnetic field lines.

“By imaging polarized light from glowing gas near a black hole, we are directly inferring the structure and strength of the magnetic field that flows through the streams of gas and matter that the black hole feeds and ejects.” said Dr. Angelo Ricarte. Astronomer at Harvard University and the Harvard & Smithsonian Center for Astrophysics.

“Polarized light can tell us much more about astrophysics, the properties of the gas, and the mechanisms that occur when black holes feed.”

But imaging black holes under polarized light isn’t as easy as wearing polarized sunglasses. This is especially true for Sagittarius A*. Sagittarius A* changes so quickly that you can’t stand still and take a photo.

Imaging supermassive black holes requires sophisticated tools beyond those previously used to capture a more stable target, M87*.

“Sagittarius A*s are like enthusiastic toddlers,” said Avery Broderick, a professor at the University of Waterloo.

“For the first time, we see invisible structures that guide matter within a black hole’s disk, drive plasma to the event horizon, and help the plasma grow.”

“Sagittarius A* moves around while trying to photograph it, so it was difficult to even construct an unpolarized image,” said astronomer Dr. Jeffrey Bower of the Institute of Astronomy and Astrophysics, Academia Sinica in Taipei. Told.

“The first image is an average of multiple images from the movement of Sagittarius A*.”

“I was relieved that polarized imaging was also possible. Some models had too much scrambling and turbulence to build polarized images, but nature isn’t that cruel. did.”

Professor Maria Felicia de Laurentiis, University of Naples Federico II, said: “Using samples of two black holes with very different masses and host galaxies, we can determine what they agree on and what they do not agree on.” It’s important.

“Since both point us toward strong magnetic fields, this suggests that this may be a universal and perhaps fundamental feature of this type of system.”

“One similarity between these two black holes could be a jet. But while we imaged a very obvious black hole in M87*, we have yet to find one in Sagittarius A*. not.”

The results of this research are published in two papers (paper #1 & paper #2) in Astrophysics Journal Letter.

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Collaboration with Event Horizon Telescope. 2024. Horizon telescope results for the first Sagittarius A* event. VII. Polarization of the ring. APJL 964, L25; doi: 10.3847/2041-8213/ad2df0

Collaboration with Event Horizon Telescope. 2024. Horizon telescope results for the first Sagittarius A* event. VIII. Physical interpretation of polarization rings. APJL 964, L26; doi: 10.3847/2041-8213/ad2df1

Source: www.sci.news

Revealing the Magnetic Field Swirling Around Our Galaxy’s Black Hole through a New Perspective

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Black hole Sagittarius A* seen in polarized light

European Southern Observatory (ESO)

This is a supermassive black hole at the center of a galaxy that we have never seen before. The image reveals a swirling magnetic field around Sagittarius A* (Sgr A*), suggesting it may be producing jets of high-energy material that astronomers have not yet seen.

This photo was taken by a network of observatories around the world operating as a single giant telescope called the Event Horizon Telescope (EHT). In 2022, the first images of Sgr A* were produced, revealing light emanating from swirling hot plasma set against the dark background of a black hole's event horizon. There, light cannot escape the extreme gravity.

Now, EHT researchers Jiri Yunshi The researchers from University College London measured how this light is polarized, or the direction of the electromagnetic field, and showed the direction and strength of the magnetic field around Sgr A*.

This image is very similar to the magnetic field of M87*, the first black hole studied by EHT. Given that M87* is about 1,500 times more massive than Sgr A*, this suggests that supermassive black holes may have similar structures regardless of their size, Yunshi says.

The two black holes photographed by the Event Horizon Telescope are strikingly similar.

European Southern Observatory (ESO)

One major difference between M87* and the black holes in our galaxy is the absence of visible high-energy jets visible from Sgr A*. This lack has long puzzled astronomers, but the fact that Sgr A* has a magnetic field like M87* suggests that our galaxy's black hole may also have jets. It suggests.

“There are very interesting hints that there may be additional structures,” Yunshi says. “I think something very exciting could be happening at the center of the galaxy, and we need to track these results.”

This makes sense given other evidence for jets that may have existed long before the galaxy's history, such as Fermi bubbles, large balls of X-ray-producing plasma above and below the Milky Way. Masu.

In addition to revealing potential hidden jets, the properties of magnetic fields also solve other astrophysical mysteries, such as how particles like cosmic rays and neutrinos are accelerated to ultrahigh energies. This could help solve the problem, Yunshi said. “Magnetic fields are the basis of all of this. Anything that yields further insight into how black holes and magnetic fields interact is of just fundamental importance to astrophysics.”

Yunshi and his colleagues hope to use a larger telescope network and more advanced equipment to take more images of Sgr A*, which will help them understand the nature of the magnetic field and how it directs the jet. This will deepen your understanding of what is being generated. EHT plans to begin these observations in April, but processing the data could take several years.

References: Astrophysics Journal LetterDoi: 10.3847/2041-8213/ad2df0 &DOI: 10.3847/2041-8213/ad2df1

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Source: www.newscientist.com

How to create a functional Dune force field

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Within the vast expanse of space, the Holtzmann Shield serves as a mobile force field capable of shielding individual soldiers in combat. This shield, generated by a device attached to a belt, can divert fast-moving projectiles away from the wearer, although slow-moving objects like combat knives can breach the barrier.

Creating such force fields presents a significant challenge in reality. Gravity, electromagnetism, and the strong and weak nuclear forces are the four fundamental forces in nature. While gravity is too feeble to function as a local force field, the nuclear force is robust but limited to the atomic nucleus.

Physicist Professor Jim Al Khaliliand researchers at the University of Surrey are exploring the possibilities of constructing force fields based on electromagnetism, a force more potent than gravity and with a longer reach compared to the nuclear force. However, this force only affects charged objects, necessitating the charging of detected flying objects.

One proposed method involves bombarding objects with positron beams, which are antimatter particles with the same mass as electrons but opposite charge. The annihilation of positrons and electrons can potentially charge and deflect incoming projectiles, offering a route to building force fields.

Though theoretically possible, this technology is likely a distant prospect, possibly not materializing for another 20,000 years. In the meantime, research is underway on electric armor for tanks, which replaces heavy steel plates with energized thin metal plates separated by insulation to store a significant charge. This innovative armor system improves efficiency and reduces weight, enhancing the agility of armored vehicles.

Source: www.sciencefocus.com

The impact of chip-integrated lasers on the field of photonics

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Chip-scale ultrafast mode-locked laser based on nanophotonic lithium niobate.Credit: Alireza Marandi

Researchers have developed a compact mode-locked laser integrated into a nanophotonic platform that can generate ultrafast light pulses at high power. This breakthrough in the miniaturization of MLL technology has the potential to significantly expand photonics applications.

Innovation in mode-locked laser technology

Setting out to improve a technology that typically requires bulky benchtop equipment, Quishi Guo and colleagues have miniaturized a mode-locked laser (MLL) with an integrated nanophotonics platform to the size of an optical chip. This result shows promise for the development of ultrafast nanophotonics systems for a wide range of applications.

Possibility of small MLL

Model-locked lasers (MLLs) can generate coherent ultrashort pulses of light at very fast speeds on the order of picoseconds to femtoseconds. These devices have enabled numerous techniques in the field of photonics, including extreme nonlinear optics.photon Microscopy and optical computing.

However, most MLLs are expensive, power-hungry, and require bulky, separate optical components and equipment. As a result, the use of ultrafast photonic systems has generally been limited to benchtop laboratory experiments. Furthermore, so-called “integrated” MLLs aimed at driving nanophotonics platforms have significant limitations, such as low peak power and lack of controllability.

Breakthrough advances in nanophotonics MLL integration

Through hybrid integration of semiconductor optical amplification chips and novel thin-film lithium niobate nanophotonic circuits, Guo other. We created an optical chip-sized integrated MLL.

According to the authors, this MLL generates ultrashort light pulses of about 4.8 picoseconds at about 1065 nanometers with a maximum output of about 0.5 watts. This is the highest output pulse energy and peak power of any MLL integrated into a nanophotonics platform.

Furthermore, the researchers show that the repetition rate of the integrated MLL can be tuned over a range of about 200 MHz and that the coherence properties of the laser can be precisely controlled, creating a fully stable on-chip nanophotonic frequency comb source. provided a path to.

Learn more about this breakthrough advancement below.

Reference: “Ultrafast mode-locked lasers in nanophotonic lithium niobate” Qiushi Guo, Benjamin K. Gutierrez, Ryotosekine, Robert M. Gray, James A. Williams, Luis Ledezma, Luis Costa, Arkadev Roy, Selina Zhou, Mingchen Liu, and Alireza Marandi, November 9, 2023; science.
DOI: 10.1126/science.adj5438

Source: scitechdaily.com