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Scientists Discover Largest Black Hole Flare Ever Recorded, Emitting 10 Trillion Solar Rays

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A supermassive black hole has violently consumed a massive star, resulting in a cosmic explosion that shone as brightly as 10 trillion suns, according to a recent study.

This event, referred to as a black hole flare, is believed to be the largest and most remote ever detected.

“This is genuinely a one-in-a-million occurrence,” stated Matthew Graham, a research professor of astronomy at the California Institute of Technology and the lead author of the study published Tuesday in Nature Astronomy.

Graham indicated that based on the explosion’s intensity and duration, a black hole flare is likely the explanation, but further studies will be necessary to validate this conclusion.

While it is common for black holes to devour nearby stars, gas, dust, and other materials, such significant flare events are exceptionally rare, according to Graham.

“This enormous flare is far more energetic than anything we’ve encountered previously,” he remarked, noting that the explosion’s peak luminosity was 30 times that of any black hole flare documented so far.

Its extreme intensity is partly due to the massive size of the celestial objects involved. The star that came too close to the black hole is estimated to possess at least 30 times the mass of the Sun, while the supermassive black hole and its surrounding matter disk are estimated to be 500 million times more massive than the Sun.

Graham mentioned that these powerful explosions have persisted for more than seven years and are likely still ongoing.

The flare was initially detected in 2018 during a comprehensive sky survey using three ground-based telescopes. At the time, it was identified as a “particularly bright object,” but follow-up observations months later yielded little valuable data.

Consequently, black hole flares were mostly overlooked until 2023, when Graham and his team opted to revisit some intriguing findings from their earlier research. Astronomers have since managed to roughly ascertain the distance to this exceptionally bright object, and the results were astonishing.

“Suddenly, I thought, ‘Wow, this is actually quite far away,'” Graham explained. “And if it’s this far away and this bright, how much energy is it emitting? This is both unusual and intriguing.”

While the exact circumstances of the star’s demise remain unclear, Graham hypothesized that a cosmic collision might have nudged the star from its typical orbit around the black hole, leading to a close encounter.

This finding enhances our understanding of black hole behavior and evolution.

“Our perspective on supermassive black holes and their environments has dramatically transformed over the past five to ten years,” Graham stated. “We once pictured most galaxies in the universe with a supermassive black hole at the center, idly rumbling away. We now recognize it as a much more dynamic setting, and we are just beginning to explore its complexities.”

He noted that while the flares are gradually diminishing over time, they will remain detectable with ground-based telescopes for several more years.

Source: www.nbcnews.com

What Is the Origin of Deep Space Gamma Rays?

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Long before astronomers proposed the Big Bang theory, they understood that the universe is infinite, remains constant over time, and that there are no dark patches in the night sky if it is indeed filled with stars. If stars populate space uniformly, then starlight would illuminate every point in the sky. Consequently, if this light persisted over time, it would illuminate Earth equally, making the sky uniformly bright.

This insight is known as Olbers’ Paradox, which suggests that the universe is neither infinite nor static, as it contains gaps of darkness between stars. Instead, astronomers agree that the universe has evolved over time, originating from the Big Bang. These transformations prevent the sky from being completely filled with starlight because, even if the universe were infinite and abundant with stars, only some would have had enough time to reach Earth.

The sky is not merely filled with starlight; it is awash with various light types. The most prominent is the long-wavelength radiation remaining from the Big Bang, known as the Cosmic Microwave Background, or CMB. Additionally, short-wavelength radiation emanates from beyond our galaxy, termed the Extragalactic Gamma-Ray Background, or EGB. The origins of EGB are more elusive compared to CMB, with possible sources ranging from black holes in distant galaxies to reactions of subatomic particles and even dark matter.

Since the discovery of EGB in the 1970s, scientists have pinpointed specific large, high-energy objects such as active galactic nuclei, which comprise nearly half of the EGB. These entities produce bright spots of resolved EGB that are observable from Earth.

This accounts for only part of the EGB, leaving the other half unresolved. The unresolved EGB is distributed across the sky, with sources too distant to be identified by telescopes. To investigate unresolved EGB sources, a scientific team explored the hypothesis that galaxies are significant, if not the primary, contributors. They deduced that nearby galaxies may account for resolved EGBs, implying that distant galaxies could be sources of the diffuse, unresolved EGBs.

It is believed that galaxies generate gamma rays through a series of events; firstly, a star is formed, which may either explode or undergo a supernova event. Supernovae accelerate particles, such as protons and electrons, to high velocities, creating cosmic rays. These cosmic rays then collide, releasing energy and initiating a chain reaction that leads to the formation of high-energy gamma rays, existing within a specific energy range of approximately 0.01–1,000 Giga-electronvolts (GEVs).

Researchers have developed a model to estimate the gamma radiation that galaxies are capable of producing and the energy levels of that radiation. This model derives two equations to calculate how frequently a galaxy generates cosmic rays based on its star production rate. Physical attributes of the galaxy, including mass, radius, and star formation rate, were necessary to finalize the model.

Data was collected from 22,087 galaxies in the Goods-S Catalog using the Hubble Space Telescope. They utilized the model to estimate the gamma radiation contributions these galaxies could provide to small regions of the sky, comparing the model’s estimates with actual gamma radiation observations from each galaxy obtained through the Fermi Gamma-Ray Telescope.

The results indicated that within the 1-10 GEV energy range of gamma radiation, these galaxies might account for 50-60% of the unresolved EGB across all observed areas. Furthermore, the contribution from galaxies diminishes sharply below 1 GEV and above 10 GEV. Their findings suggest that earlier research into the star-forming galaxy hypothesis may have underestimated their contributions to the unresolved EGB.

The team concluded that beyond star-forming galaxies, other sources must account for the unresolved EGB found in deep space. They propose that future research focus on active galactic nuclei and millisecond pulsars as potentially fruitful candidates. This observation indicates the possibility of other unexplored phenomena, suggesting that galaxies may not be the primary sources of unresolved EGBs. The disappearance of dark matter could be a piece of this cosmic puzzle.

Where does Deep Space Gamma Ray come from? It first appeared in Sciworthy.

Source: sciworthy.com

Underground Microbial Life Could Endure on Mars, Europa, and Enceladus with the Help of Cosmic Rays

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A recent study conducted by New York University Abu Dhabi suggests that radiolysis, triggered by cosmic rays in galaxies, may serve as a potential energy source for microbial metabolism within the subsurface environments of rocky celestial bodies such as Mars, Europa, and Enceladus.

NASA’s Cassini spacecraft captured this stunning mosaic of Enceladus as it flew past this geologically active moon of Saturn on October 5, 2008. Image credit: NASA/JPL/Space Science Institute.

While ionized radiation is known for its detrimental effects on biological systems, such as causing damage to DNA and generating reactive oxygen species, it can also yield biologically beneficial outcomes.

Though direct exposure to high radiation levels can be harmful to biological activity, ionizing radiation can create numerous biologically useful products.

One such process involves the generation of valuable biological products through charged particle-induced radiolysis.

“We investigated the consequences of cosmic rays striking surfaces containing water or ice,” noted Dr. Dimitra Atli, PhD, from New York University Abu Dhabi, alongside colleagues from Washington University, the University of Tennessee, Rice University, and Santander University.

“The impact of these rays breaks down water molecules and releases tiny particles known as electrons.”

“Certain bacteria on Earth are capable of utilizing these electrons for energy, akin to how plants harness sunlight.”

“This phenomenon, known as radiolysis, allows for life to persist in dark, cold environments devoid of sunlight.”

This newly reorganized color view presents a massive surface of Europa. The image scale is 1.6 km per pixel, with the northern part of Europa on the right. Image credit: NASA/JPL-Caltech/Seti Institute.

Researchers utilized computer simulations to assess the energy output of this process on the icy moons of Mars, Jupiter, and Saturn.

These icy moons are believed to harbor liquid water beneath their thick ice crusts.

Findings indicate that Enceladus is the most promising candidate for supporting life in this manner, followed closely by Mars and Europa.

“This discovery reshapes our understanding of potential habitats for life,” Dr. Atri commented.

“Rather than confining our search to warm, sunlit planets, we can now consider cold, dark regions where water lies beneath the surface and is subjected to cosmic rays.”

“Life might exist in many more locations than previously thought.”

This image captured by Mars Express’s high-resolution stereo camera reveals an overview of Mars, with patches of yellow, orange, blue, and green on a muted gray background, depicting various surface compositions. Image credits: ESA/DLR/FU BERLIN/G. MICHAEL/CC BY-SA 3.0 IGO.

In their research, the authors introduce a new concept termed the Radiolysis Habit Zone.

Unlike the traditional “Goldilocks zone”—the region around a star where planets can sustain liquid water—this new zone emphasizes the potential for subsurface water that can be energized by cosmic radiation.

Given that cosmic rays are ubiquitous throughout the universe, this suggests that numerous additional locations may harbor life.

“These findings offer fresh directions for future space exploration,” remarked Reservers.

“Scientists can target the underground environments of these icy moons and Mars instead of solely searching for life on their surfaces.

“This study paves the way for thrilling new avenues in life exploration across the cosmos, implying that even the coldest and darkest regions may have conditions suitable for life.”

The study will be published in International Journal of Astrobiology.

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Dimitra Atri et al. 2025. Estimating the potential of ionizing radiation-induced radiolysis for microbial metabolism in Earth’s planets and moons with tenuous atmospheres. International Journal of Astrobiology 24:E9; doi:10.1017/s1473550425100025

Source: www.sci.news

We May Have Finally Cracked the Mystery of Ultra-High Energy Cosmic Rays

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Artistic rendering inspired by actual images of the IceCube neutrino detectors in Antarctica.

icecube/nsf

Our focus lies in understanding the true nature of the rarest and most energetic cosmic rays, which aids in deciphering their elusive origins.

The universe continuously showers us with bursts of particles. Brian Clark, from the University of Maryland, explains that the most energetic particles are termed ultra-high energy cosmic rays, possessing more energy than particles accelerated in labs. However, they are quite rare. Researchers are still investigating their sources and the constituent particles remain largely unidentified. Clark and his team are now analyzing the composition using data from the IceCube Neutrino detector situated in Antarctica.

Previous detections of ultra-high energy cosmic rays by the Pierre Auger Observatory in Argentina and a telescope array in Utah have led to disagreements. Clark posits that it remains uncertain whether these rays are mainly composed of protons or if they consist of a mix of other particles. The IceCube data sheds light on this, indicating that protons account for about 70% of these rays, with the remainder composed of heavier ions like iron.

Team member Maximilian Meyer from Chiba University in Japan notes that while IceCube data complements other measurements, it primarily detects neutrinos—by-products resulting from collisions between ultra-high-energy cosmic rays and residual photons from the Big Bang. Detecting and simulating neutrinos is inherently challenging.

The characteristics of cosmic ray particles influence how the magnetic fields generated in space affect their trajectories. Thus, comprehending their structure is crucial for the challenging endeavor of tracing their origins, according to Toshihiro Fujii from Osaka Metropolitan University in Japan.

These mysterious origins have given rise to numerous astonishing enigmas, such as the Amaterasu particle cosmic rays. Interestingly, it seems to have originated from a region in space near the Milky Way that lacks clear astronomical candidates for its source.

Clark expresses optimism about solving many of these mysteries within the next decade, as new observational tools, including an upgrade to IceCube, will soon be operational. “This domain has a clear roadmap for how we can address some of these questions,” he states.

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Source: www.newscientist.com

Understanding Sunburn: The Role of UV Rays in Triggering Inflammation

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Taking refuge in the shade is a simple way to steer clear of harmful UV rays from the sun.

Paul Biggins/Alamy

Since ancient Egyptian times, individuals have sought ways to shield their skin from the sun, as over a century ago, we recognized the link between ultraviolet (UV) light and skin injuries, including burns and cancers. Yet, there remains some uncertainty regarding the most effective methods to evade sunburn, how to remedy it, and whether each occurrence escalates the chances of developing cancer. It’s beneficial to grasp the cellular dynamics of tanning.

“Sunburn is an inflammatory response,” explains Leslie Rhodes from the University of Manchester, UK. UV rays inflict damage to proteins, fats, and DNA in skin cells located in the epidermis, triggering a cascade of inflammatory reactions resulting in redness, swelling, pain, and peeling.

Though UVB radiation is chiefly responsible for this damage, UVA rays, which have longer wavelengths, penetrate the skin more deeply. “Typically, UVB is approximately 1,000 times more effective than UVA for sunburning,” states Antony Young from King’s College London.

In reaction to UV injury, skin cells emit inflammatory molecules that enlarge blood vessels in the dermis, the layer of skin beneath the epidermis. Within hours, this increased blood circulation facilitates the influx of immune cells from the bloodstream into the skin, heightening inflammation.

For individuals with lighter skin tones, this augmented blood flow may cause sun-damaged skin to appear pink or red, while those with darker skin might notice skin changes in various shades including red, gray, brown, and black. The enhanced blood supply also results in greater fluid leakage from blood vessels to the skin, leading to swelling. Both swelling and inflammatory molecules activate the nerves, rendering the tanned skin hot and painful.

In extreme cases, blisters may form if patches of epidermal cells become severely damaged and begin self-destructing. As these dead patches detach from the underlying layer, the resulting spaces fill with liquid, creating a foamy structure within the skin.

How does tanned skin heal?

According to Rhodes, “A mild tan will diminish more rapidly than a severe burn if the effects persist beyond 72 hours.”

Healing initiates when skin immune cells start generating anti-inflammatory molecules a few days post UV exposure. “It’s a self-resolving inflammation,” Rhodes notes. “The various molecules and cells transition over time from pro-inflammatory to anti-inflammatory states.” Consequently, blood vessels cease to dilate, and the redness, swelling, and pain gradually subside.

Stem cells situated at the base of the epidermis accelerate healing by producing new skin cells at an increased rate. These cells replace the damaged ones, often shedding or peeling off in large sheets to facilitate growth. “You always shed skin, but UV damage accelerates the conversion of those cells,” says Young.

Regrettably, there is insufficient evidence to suggest that applying after-sun or aloe vera gels can hasten healing of tanned skin, according to Rhodes. Most of these lotions aim to alleviate pain by providing a cooling sensation. Cold showers, cool compresses, and over-the-counter pain relievers like paracetamol (acetaminophen) and ibuprofen may also be beneficial.

What are the long-term effects?

The sunburn subsides as inflammation lessens and damaged surface cells slough off. However, DNA damage to deeper stem cells in the epidermis may leave a lasting legacy.

“DNA damage occurs, and while cells attempt to repair it, their efforts are not flawless,” notes Young. This leads to genetic mutations that accumulate over time in genes governing cell growth and division, resulting in uncontrolled skin cell proliferation, heightening cancer risks.

Numerous studies indicate that experiencing five sunburns within a decade more than doubles the risk of melanoma, a type of skin cancer. However, these findings often rely on individuals’ recollections of their sunburn occurrences, which may not be precise, complicating the accurate assessment of how a single sunburn contributes to skin cancer risk.

What is the best method to prevent sunburn?

The skin pigment melanin encircles skin cell DNA, offering some level of protection from UV damage. Consequently, individuals with darker skin tones face a significantly lower risk of skin cancer compared to those with lighter complexions, though they are not immune to sunburn or DNA damage.

To assess the risk of burning on any given day, monitor the UV index, which measures ultraviolet radiation levels. Rachel Abbott from the University Hospital of Wales, Cardiff, advises applying sunscreen if the index reaches 3 or higher. Typically, UV indexes seldom exceed 3 early in the morning, evening, or between October and March in the UK. Nonetheless, UV rays are more intense near the equator and may necessitate sunscreen application at any time. Fortunately, free apps provide local UV index information. “I use one daily,” Abbott shares.

Most individuals don’t apply sunscreen with the thickness utilized in testing—2 milligrams per square centimeter—making an SPF 50 sunscreen a wise default choice, according to Young.

Nevertheless, one of the most effective strategies to prevent sunburn is to avoid direct sunlight when it is highest in the sky. In the UK, this window is between 11 a.m. and 3 p.m., while in the US, it generally extends from 10 a.m. to 4 p.m. During this time, sunlight takes a shorter route through the atmosphere, allowing more UVB radiation to reach the skin. When outdoors, donning a hat and long-sleeved clothing can further diminish the risk.

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Source: www.newscientist.com

Physicists suggest that ultra-high energy cosmic rays originate from neutron star mergers

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Ultra-high energy cosmic rays are the highest energy particles in the universe, and their energy is more than one million times greater than what humans can achieve.

Professor Farrar proposes that the merger of binary neutron stars is the source of all or most ultra-high energy cosmic rays. This scenario can explain the unprecedented, mysterious range of ultra-high energy cosmic rays, as the jets of binary neutron star mergers are generated by gravity-driven dynamos and therefore are roughly the same due to the narrow range of binary neutron star masses. Image credit: Osaka Metropolitan University / L-Insight, Kyoto University / Riunosuke Takeshige.

The existence of ultra-high energy cosmic rays has been known for nearly 60 years, but astrophysicists have not been able to formulate a satisfactory explanation of the origins that explain all observations to date.

A new theory introduced by Glennnies Farrer at New York University provides a viable and testable explanation of how ultra-high energy cosmic rays are created.

“After 60 years of effort, it is possible that the origins of the mysterious highest energy particles in the universe have finally been identified,” Professor Farrar said.

“This insight provides a new tool to understand the most intense events in the universe. The two neutron stars fuse to form a black hole. This is the process responsible for creating many valuable or exotic elements, including gold, platinum, uranium, iodine, and Zenon.”

Professor Farrer proposes that ultra-high energy cosmic rays are accelerated by the turbulent magnetic runoff of the dual neutron star merger, which was ejected from the remnants of the merger, before the final black hole formation.

This process simultaneously generates powerful gravitational waves. Some have already been detected by scientists from the Ligo-Virgo collaboration.

“For the first time, this work explains two of the most mystical features of ultra-high energy cosmic rays: the harsh correlation between energy and charge, and the extraordinary energy of just a handful of very high energy events,” Professor Farrar said.

“The results of this study are two results that can provide experimental validation in future work.

(i) Very high energy cosmic rays occur as rare “R process” elements such as Xenon and Tellurium, motivating the search for such components of ultra-high energy cosmic ray data.

(ii) Very high-energy neutrinos derived from ultra-high-energy cosmic ray collisions are necessarily accompanied by gravitational waves generated by the merger of proneutron stars. ”

study It will be displayed in the journal Physical Review Letter.

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Glennys R. Farrar. 2025. Merger of dichotomous neutron stars as the source of the finest energy cosmic rays. Phys. Pastor Rett 134, 081003; doi:10.1103/physrevlett.134.081003

Source: www.sci.news

Surprising discovery: AMS detector detects a higher-than-expected number of cosmic rays containing deuterons

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Deuteron It is believed that atomic nuclei consisting of protons and neutrons, like those of helium-3 nuclei, are formed in collisions between helium-4 nuclei and other nuclei in the interstellar medium. If this were the case, the flux ratio of deuterons to helium-4 should be similar to that of helium-3 to helium-4. However, this is not the case. Alpha Magnetic Spectrometer Astronauts aboard the International Space Station (AMS) are watching.

Aguilar othersThe deuteron flux was measured using the Alpha Magnetic Spectrometer (AMS) on board the International Space Station.

Cosmic rays are high-energy particles with energies ranging from MeV to 10.20 Electronic V.

These properties are studied from measurements of the energy (stiffness) spectrum (number of particles per unit time, solid angle, surface area, and energy as a function of energy), which is characterized by a rapid decrease in the spectrum as the energy increases.

Cosmic rays with energies below PeV are thought to originate in our own Milky Way galaxy.

The elemental composition of these galactic cosmic rays is dominated by hydrogen nuclei, primarily protons, with helium nuclei making up about 10%, and electrons and nuclei heavier than helium making up just 1% each.

The species synthesized in stars, such as protons, electrons, and most atomic nuclei, are called primary cosmic rays.

Light nuclei, synthesized by nuclear fusion in the cores of stars, are more abundant than heavy nuclei because their production becomes energetically unfavorable as mass increases.

The synthesis of atomic nuclei heavier than iron, such as nickel, occurs through explosive phenomena such as supernova explosions that occur at the end of the life of massive stars, so atomic nuclei heavier than iron are extremely rare.

When primary nuclei are ejected from their source in space, they can collide with interstellar material and split into lighter species.

This is the primary production mechanism for atomic nuclei that are energetically unfavorable to produce by stellar nucleosynthesis, such as lithium, beryllium, boron, fluorine, scandium, titanium, and vanadium. These are called secondary cosmic rays.

Compared to primary nuclei of similar mass, secondary nuclei are less abundant and, as stiffness increases, their stiffness spectrum decreases faster than that of primary nuclei.

The energy (or rigidity) dependence of the cosmic ray spectrum arises from a combination of source-directed emission, acceleration, and propagation mechanisms that occur during a cosmic ray's passage through the galaxy.

Cosmic rays are diffusely accelerated by expanding shock waves, propagate diffusely through the interstellar medium, and are scattered by irregularities in the galactic magnetic field, both of which depend on the particle's momentum, and thus on its magnetic stiffness.

Cosmic ray propagation is described by a stiffness-dependent diffusion coefficient that incorporates the properties of turbulence in the galactic magnetic field.

“Hydrogen nuclei are the most abundant species of cosmic ray,” members of the AMS collaboration wrote in the paper.

“They are made up of two stable isotopes: protons and deuterons.”

“Big Bang nucleosynthesis predicts negligible production of deuterium, and over time the abundance of deuterons has decreased from its primordial value, with the ratio of deuterons to protons measured in the interstellar medium being 0.00002.”

“Deuterons are thought to arise primarily from the interaction of helium with interstellar matter, rather than being accelerated in supernova remnants like primary cosmic ray protons and helium-4.”

“Deuterons, along with helium-3, are called secondary cosmic rays.”

For the latest study, AMS physicists examined data from 21 million cosmic deuterons detected by AMS between May 2011 and April 2021.

When investigating how the deuteron flux varies with rigidity, a surprising feature was discovered.

The AMS data show that these ratios differ significantly above a stiffness of 4.5 GV, with the deuteron to helium-4 ratio decreasing more slowly with stiffness than the helium-3 to helium-4 ratio.

Furthermore, and again contrary to expectations, when stiffness exceeds 13 GV, the data show that the flux of deuterons is nearly the same as the flux of protons, the primary cosmic ray.

Simply put, researchers found more deuterons than expected from collisions between main helium-4 nuclei and interstellar matter.

“Measuring deuterons is very challenging due to the large cosmic proton background radiation,” said Dr Samuel Ting, spokesman for the AMS collaboration.

“Our unexpected results show how little we know about cosmic rays.”

“Future upgrades to AMS will increase the acceptance rate by 300 percent, enabling AMS to measure all charged cosmic rays with 1 percent accuracy, providing the experimental basis for the development of accurate cosmic ray theory.”

The team's paper was published in the journal Physics Review Letter.

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M. Aguilar others(AMS Collaboration). 2024. Properties of cosmic deuterons measured with the Alpha Magnetic Spectrometer. Physiotherapy Rev Lett 132(26):261001;doi:10.1103/PhysRevLett.132.261001

Source: www.sci.news

Fermi makes a puzzling discovery of gamma rays from beyond our galaxy

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Interestingly, the gamma-ray signal detected by NASA's Fermi Gamma-ray Space Telescope has a similar orientation to another unexplained feature produced by some of the most energetic cosmic particles ever detected. and are found to be approximately the same size.

This artist's concept shows the entire sky in gamma rays, with a magenta circle indicating the uncertainty in the direction in which more high-energy gamma rays appear to be arriving than average. In this view, the plane of the Milky Way crosses the center of the map. The circle encloses the region that contains these gamma ray sources with a probability of 68% (inside) and 95%. Image credit: NASA's Goddard Space Flight Center.

“It was a completely serendipitous discovery. We found a much stronger signal in a different part of the sky than what we were looking for,” said the University of Maryland and NASA's Goddard Space Flight Center in Space. said academic Dr. Alexander Kashlinsky.

Dr. Kasilinsky and his colleagues were looking for gamma-ray signatures associated with the cosmic microwave background (CMB), the oldest light in the universe.

This light occurred when the hot, expanding universe cooled enough to form the first atoms, and this event released a burst of light that could penetrate the universe for the first time.

Stretched out by the subsequent expansion of the universe over the past 13 billion years, this light was first detected in 1965 in the form of faint microwave waves across the sky.

In the 1970s, astronomers noticed that the CMB had a so-called dipole structure, which was later measured with high precision by NASA's COBE mission.

The CMB has more microwaves than average in the direction toward Leo and is about 0.12% hotter, and in the opposite direction it is cooler by the same amount with fewer microwaves than average.

To study small temperature changes within the CMB, this signal must be removed.

Astronomers generally believe that this pattern is the result of our solar system's motion relative to the CMB at about 370 km per second (230 miles per second).

This movement causes a dipole signal in the light coming from astrophysical sources, but so far only the CMB has been accurately measured.

By looking for patterns in other forms of light, astronomers can confirm or refute the idea that the dipole is entirely due to the motion of the solar system.

“Such measurements are important because the discrepancy in the size and orientation of the CMB dipole allows us to extend the possibility of going back to the very beginning of the universe, when the universe was less than a trillionth of a second old. “Because we can get a glimpse of certain physical processes,” said Professor Fernando Atrio Barrandera from the University of Salamanca.

Astronomers reasoned this by summing up years of data from Fermi's Large Area Telescope (LAT).

Due to the effects of relativity, gamma-ray dipoles should be amplified five times more than currently detected CMBs.

The authors integrated 13 years of Fermi LAT observations of gamma rays above about 3 billion electron volts (GeV). For comparison, visible light has an energy of about 2 to 3 electron volts.

They removed all resolved and identified sources and removed the central plane of the Milky Way to analyze the extragalactic gamma-ray background.

“We have discovered a gamma-ray dipole, but its peak is located in the southern sky, far from the CMB, and its magnitude is 10 times larger than expected from our motion.” said astrophysicist Dr. Chris Schroeder. Catholic University of America.

“Although this is not what we were looking for, we think it may be related to similar features reported for the highest-energy cosmic rays.”

Cosmic rays are accelerated charged particles, primarily protons and atomic nuclei. The rarest and most energetic particles, called UHECRs (Ultra High Energy Cosmic Rays), carry more than a billion times the energy of 3 GeV gamma rays, and their origin remains one of the greatest mysteries in astrophysics.

Since 2017, the Pierre Auger Observatory in Argentina has report Dipole in the direction of arrival of UHECR.

Because cosmic rays are electrically charged, they are deflected by galaxies' magnetic fields by different amounts depending on their energy, but the peak of the UHECR dipole is at a position in the sky similar to that found by researchers with gamma rays.

And both have surprisingly similar sizes. About 7% more gamma rays or particles than average come from one direction, and correspondingly less gamma rays or particles come from the opposite direction.

“The two phenomena are probably related, and an as-yet-unidentified source may be producing both gamma rays and very high-energy particles,” the scientists said.

“To solve this cosmic puzzle, we must either locate these mysterious sources or propose alternative explanations for both features.”

of findings Published in Astrophysics Journal Letter.

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A. Kashirinsky other. 2024. Exploration of dipoles in the diffuse gamma-ray background. APJL 961, L1; doi: 10.3847/2041-8213/acfedd

Source: www.sci.news

The Top Animal Photos of 2023: From Hyenas to Southern Rays

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Spotted Hyena

This spotted hyena (Crokuta Crokuta) is a natural in front of the camera, while its mother and siblings watch closely in the background. This playful shot was taken by Wim van den Heever in Amboseli National Park in southern Kenya.

Southern Stingray

As the sun rises over the coast of the Cayman Islands, southern rays (Dashatis Americana) are captured in this striking split-level snap by the photographer, Alex Mustard, as they wander on a sandy beach.

Slug Sucking Sap

A brightly fluorescent animal known as the sap-sucking slug (Costasiella crocimae) is captured by Mustard, crawling on green algae just off the coast of northern Indonesia. This sea slug has a special ability to preserve the chloroplasts of the algae they feed on, allowing them to photosynthesize.

Eurasian Brown Bear

Deep in the forests of Finland, Andy Rouse took an action shot of a Eurasian brown bear (Ursus Arctos Arctos) after a short soak in the pond, the body trembles dry. These mammals can weigh up to 480 kilograms and are common in Eastern Europe and Russia.

Spotted Fritillary Larva

In the grasslands of the Rhodope Mountains in Bulgaria, Guy Edwards took a colorful photo of a spotted fritillary (Melitaea Didyma) larvae. It eventually transforms into a butterfly, its wings becoming bright orange with brown spots.

White Winged Snowfinch

The majestic white-winged snowfinch (Montifringilla Nivalis) is captured braving a snowstorm in the Swiss Alps by Mateusz Piesiak. It is a relatively large and sturdy bird, reaching up to 19 centimeters in height.

Fruit Bat

This bewildered fruit bat has its nose and throat swabbed as part of an effort in the Republic of Congo to better understand how zoonotic diseases such as Ebola are transmitted to people. Researchers from the Wildlife Conservation Society and Congo Medical Research Foundation collected blood and saliva samples from about 100 fruit bats.

Source: www.newscientist.com

Unraveling Subtle Mysteries with “Donut” Rays

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Researchers at the University of Boulder have advanced the field of ptychography by innovating a new imaging method using donut-shaped light beams. This technique enables detailed imaging of small regularly patterned structures such as semiconductors, overcoming previous limitations of conventional microscopy. This advance promises significant improvements in nanoelectronics and biological imaging. (Artist’s concept) Credit: SciTechDaily.com

In a new study, researchers at the University of Boulder used a donut-shaped beam of light to take detailed images of objects too small to be seen with traditional microscopes.

Advances in Nanoelectronic Imaging

This new technology could help scientists improve the inner workings of a variety of ‘nanoelectronics’, including miniature ones. The semiconductor inside a computer chip. This discovery was featured in a special issue on December 1st. Optics and Photonics News called Optics in 2023.

Ptychography: A Lens into the Microscopic World

This research is the latest advance in the field of ptychography, a challenging yet powerful technique for seeing very small things. Unlike traditional microscopes, ptychography tools do not directly observe small objects. Instead, it shines a laser at a target and measures how the light is scattered. This is a bit like making shadow puppets on a wall when viewed through a microscope.

A scattering pattern produced by donut-shaped rays of light reflecting off an object with a regularly repeating structure. Credit: Wang et al., 2023, optica

Overcoming Ptychography Challenges

So far, the approach has worked surprisingly well, with one major exception, said Margaret Mahne, the study’s lead author and distinguished professor of physics.

“Until recently, we had been completely unsuccessful with highly periodic samples or objects with regularly repeating patterns,” says the UW-Boulder and National Institute of Standards and Technology (NIST) collaboration. Margaret, a fellow at JILA, said, “That’s a problem because this has a lot of nanoelectronics in it.”

She pointed out that many important technologies, such as some semiconductors, are made up of atoms such as silicon and carbon bonded in regular patterns, like small grids or meshes. So far, it has proven difficult for scientists to observe these structures up close using ptychography.

Donut-shaped beams of light scatter from incredibly small structures. Credit: Wang et al., 2023, optica

A Breakthrough in Donut-Shaped Light

But in a new study, Murunet and colleagues have come up with a solution. Instead of using a traditional laser in a microscope, they generated a donut-shaped beam of extreme ultraviolet light.

The researchers’ new approach can collect precise images of small, delicate structures that are around 10 to 100 nanometers in size, or many times smaller than a millionth of an inch. In the future, researchers expect to be able to zoom in and observe even smaller structures. The donut beam, or angular momentum beam of light, also does not damage small electronic equipment during the process, as existing imaging tools such as electron microscopes do.

“In the future, this method could be used to inspect polymers used in semiconductor manufacturing and printing for defects without damaging the structure during the process,” Mahne said. Stated.

Bin Wang and Nathan Brooks, who received their PhDs from JILA in 2023, are the lead authors of this new study.

Pushing the Limits of Microscopy

Mahne said this research pushes the fundamental limits of microscopy. Because of the physics of light, lens-based imaging tools can only see the world to a resolution of about 200 nanometers, which is not precise enough to capture many viruses. For example, those that infect humans. Although scientists can freeze viruses to death and view them with powerful cryo-electron microscopes, they still cannot capture the activity of these pathogens in real time.

Ptychography, developed in the mid-2000s, could help researchers break through that limit.

How ptychography works
To understand how, go back to shadow puppets. Imagine that a scientist wants to collect stylized images of very small structures, perhaps the letters that spell “CU.” To do this, they first shine a laser beam on the text and scan the text multiple times. When light hits “C” and “U” (in this case the dolls), the light rays break and scatter, creating a complex pattern (shadow). Scientists record those patterns using sensitive detectors and analyze them using a series of mathematical formulas. Given enough time, they will perfectly recreate the shape of the doll from the shadow it casts, Mahne explained.

Evolution to Finer Details

Stated. Bin Wang and Nathan Brooks, who received their PhDs from JILA in 2023, are the lead authors of this new study. Other co-authors of the new study include physics professor and JILA fellow Henry Kaptein, current and former JILA graduate students Peter Johnsen, Nicholas Jenkins, Yuka Esashi, Iona Binney, Includes Michael Tanksalvara.

Reference: “High-fidelity ptychographic imaging of highly periodic structures enabled by vortex harmonic beams” Michael Tanksalvala, Henry C. Kapteyn, Bin Wang, Peter Johnsen, Yuka Esashi, Iona Binnie, Margaret M. Murnane, Nicholas W. Jenkins, and Nathan J. Brooks, September 19, 2023, optica.
DOI: doi:10.1364/OPTICA.498619

Source: scitechdaily.com