Tag Archives: nearby

Webb Discovers Surprising Hydrocarbon Abundance in Mysterious Core of Nearby Luminous Galaxy

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Astronomers utilizing the NASA/ESA/CSA James Webb Space Telescope have identified an extraordinary presence of small gas-phase hydrocarbons—such as benzene, triacetylene, diacetylene, acetylene, methane, and methyl radicals—within the concealed core of the ultra-bright infrared galaxy IRAS 07251-0248.

Hydrocarbons are influential in shaping the chemistry of the interstellar medium. However, definite observational constraints on their enrichment and relationship with carbonaceous particles and polycyclic aromatic hydrocarbons remain elusive. García Bernete et al. report Webb infrared observations of the Local Ultraluminous Infrared Galaxy (ULIRG) IRAS 07251-0248, revealing extragalactic detections of small gas-phase hydrocarbons. Image credit: García-Bernete et al., doi: 10.1038/s41550-025-02750-0.

The core of IRAS 07251-0248 (also known as 2MASS J07273756-0254540) is obscured by significant amounts of gas and dust.

This dense material absorbs most radiation emitted by the central supermassive black hole, complicating studies with traditional telescopes.

However, the infrared spectrum can penetrate this dust, providing unique insights about these regions and illuminating vital chemical processes in this heavily obscured core.

Dr. Ismael García Bernete and his team employed spectroscopic observations using Webb’s NIRSpec and MIRI instruments, covering wavelengths from 3 to 28 microns.

These observations reveal chemical signatures of gas-phase molecules alongside signatures from ice and dust particles.

These data empowered astronomers to characterize the abundance and temperature of various chemical species within the core of this concealed galaxy.

Remarkably, they discovered an exceptionally high abundance of small organic molecules such as benzene, methane, acetylene, diacetylene, and triacetylene—the first such detections outside our Milky Way, including the methyl radical.

Additionally, substantial amounts of solid molecular materials, including carbonaceous particles and water ice, were identified.

“We uncovered unexpected chemical complexity, showcasing abundances far exceeding current theoretical models,” stated Dr. García Bernete, an astronomer at the Astrobiology Center.

“This suggests a continuous source of carbon within these galactic nuclei, fueling this rich chemical network.”

“These molecules may serve as vital building blocks for complex organic chemistry, relevant to processes that pertain to life.”

Professor Dimitra Rigopoulou from the University of Oxford remarked, “Small organic molecules may not exist in living cells, yet they could play a pivotal role in prebiotic chemistry—a crucial step toward forming amino acids and nucleotides.”

These findings were published in a recent issue of Nature Astronomy.

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I. Garcia-Bernete et al. Abundant hydrocarbons within buried galactic nuclei with evidence of processing of carbonaceous particles and polycyclic aromatic hydrocarbons. Nat Astron, published online on February 8, 2026. doi: 10.1038/s41550-025-02750-0

Source: www.sci.news

Exciting Discovery: Earth-Sized Exoplanet Found Orbiting Nearby Star

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Astronomers have recently identified a new exoplanet, HD 137010b, orbiting the nearby K dwarf star HD 137010, following the detection of a single shallow transit in archived data from NASA’s Kepler Expansion K2 mission.

HD 137010b is estimated to be 6% larger than Earth, with surface temperatures akin to those of Mars, possibly dipping below -70 degrees Celsius. Image credit: NASA/JPL-Caltech/Keith Miller, California Institute of Technology and IPAC.

HD 137010 is classified as a K3.5V dwarf star located approximately 146 light-years away in the constellation Libra.

This star’s age ranges between 4.8 billion and 10 billion years, and its low magnetic activity reflects its status as an old, relatively calm star.

Commonly referenced as BD-19 4097, HIC 75398, 2MASS J15242123-1944215, or TYC 6179-1111-1, HD 137010 has an apparent magnitude of 10.1 and is recognized as one of the brightest stars hosting an Earth-sized planet in temperate orbits.

The new exoplanet, designated HD 137010b, was observed during K2 Campaign 15 when NASA’s Kepler Space Telescope monitored its parent star for about three months in 2017.

“Most Earth-sized planets discovered in the habitable zone orbit red dwarfs, which are smaller and dimmer than the Sun,” explains lead author Astronomer Alexander Venner from the University of Southern Queensland.

“Concerns arise regarding these planets losing their atmospheres due to intense radiation from their host stars, rendering them uninhabitable for known life forms.”

“However, HD 137010b’s star shares characteristics more closely aligned with the Sun, increasing the likelihood that a stable atmosphere could be retained, according to current theoretical models.”

In their study, Venner and colleagues analyzed K2 data, light curves from nearby stars, archival images, and radial velocity measurements to clarify the nature of the transit signal, which lasted roughly 10 hours.

These evaluations strongly suggest that the observed transit is astrophysical and not a result of background interference, eclipsing binaries, or solar-system debris.

Astronomers have determined that the planet’s radius is approximately 1.06 times that of Earth based on the transit depth.

Considering the transit’s duration and the star’s properties, the orbital period of HD 137010b is estimated to be around 355 days.

At its distance from the host star, HD 137010b is estimated to receive about 29% of the stellar flux that Earth obtains from the Sun, placing it near the outskirts of the star’s habitable zone.

“If HD 137010b has an atmosphere similar to that of Earth or Mars, it could experience temperatures colder than Antarctica,” noted Dr. Venner.

“However, if the atmosphere thickens, conditions could warm up sufficiently for liquid water to exist, creating a potentially viable environment for life.”

“Current astronomical instruments are unable to fully characterize this newly discovered planet, but it stands out as a primary candidate for future radial velocity tools aimed at detecting Earth-like analogs.”

“Upcoming space missions, like NASA’s Habitable World Observatory, could also provide images of HD 137010b.”

This discovery is detailed in the following article: paper published in Astrophysics Journal Letters.

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Alexander Venner and others. 2026. A cool Earth-sized planet candidate orbiting a K2 magnitude K-dwarf star. APJL 997, L38; doi: 10.3847/2041-8213/adf06f

Source: www.sci.news

Unexpected Shock Wave Discovered Surrounding Nearby White Dwarf Star

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Astronomers utilizing ESO’s Very Large Telescope (VLT) have captured stunning shock waves surrounding the white dwarf star 1RXS J052832.5+283824 (commonly known as RXJ0528+2838). This extraordinary phenomenon challenges existing astrophysical models and has the potential to transform our understanding of stellar evolution.

Image credit: ESO / Iłkiewicz et al. showcasing the shockwave around the white dwarf RXJ0528+2838, captured by the MUSE instrument of ESO’s VLT.

Located approximately 730 light-years away in the constellation Auriga, RXJ0528+2838 orbits the center of the Milky Way, similar to our Sun and other stars.

According to Dr. Noel Castro-Segura from the University of Warwick, “As the white dwarf traverses space, it interacts with interstellar gas, causing a type of shock wave known as a bow shock, which resembles a wave building up in front of a moving ship.”

Interestingly, while bow shocks are typically produced by material expelled from the star, the mechanisms observed in RXJ0528+2838 remain unexplained.

RXJ0528+2838 is part of a binary system, with a sun-like companion star. In such systems, gas is often transferred to the white dwarf, creating an accretion disk. However, this disk appears absent, leading to questions about the source of the observed outflow and the surrounding nebula.

Dr. Simone Scaringi from Durham University expressed: “The fact that a seemingly quiet, diskless system could produce such an impressive nebula was a remarkable surprise.”

Astronomers initially identified an unusual nebula around RXJ0528+2838 through images captured by the Isaac Newton Telescope in Spain, prompting further investigation with the MUSE instrument at VLT.

The size and shape of the bow shock indicate that the white dwarf has been generating significant outflows for over 1,000 years.

Although the exact mechanism for such a prolonged outflow from a diskless white dwarf is still under investigation, scientists speculate that RXJ0528+2838 possesses a strong magnetic field, evidenced by MUSE data.

This magnetic field may funnel material directly from the companion star to the white dwarf, bypassing the formation of an accretion disk.

Dr. Christian Ikiewicz from the Nicolaus Copernicus Astronomical Center remarked, “Our findings indicate that diskless systems can still produce powerful outflows, revealing complex interactions that challenge traditional binary star models.”

While the detected magnetic field can sustain a bow shock for hundreds of years, it only partially accounts for the phenomena observed.

“We’ve uncovered something unprecedented and unexpectedly remarkable,” Dr. Scaringi noted.

For further reading on this groundbreaking discovery, refer to the published paper in the journal Nature Astronomy.

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K. Iwkiewicz et al. Persistent bow shock in a diskless magnetized accreting white dwarf. Nat Astron, published online on January 12, 2026. doi: 10.1038/s41550-025-02748-8

Source: www.sci.news

Hubble Captures Stunning Images of Star-Forming Clouds in Nearby Dwarf Galaxy

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Explore the stunning new image captured by the NASA/ESA Hubble Space Telescope, showcasing a section of the N159 star-forming complex located in the Large Magellanic Cloud, a dwarf galaxy approximately 160,000 light-years away from Earth.

This breathtaking Hubble image portrays N159, a vibrant star-forming complex in the Large Magellanic Cloud. Image credit: NASA / ESA / Hubble / R. Indebetouw.

N159 stands as one of the most colossal molecular clouds within the Large Magellanic Cloud, making it a noteworthy member of our cosmic neighborhood – the Milky Way galaxy.

Positioned at the southwestern edge of the renowned Tarantula Nebula, N159 spans over 150 light-years across.

The newly released Hubble image captures only a fraction of the expansive N159 complex.

“A dense cloud of cold hydrogen gas predominates the scene, creating a complex array of ridges, cavities, and luminescent filaments,” stated Hubble astronomers.

“Within these thick clouds, newly formed stars begin to blaze, their intense radiation illuminating the surrounding hydrogen in a striking crimson hue.”

“The brightest zones signify the presence of hot, massive young stars whose vigorous stellar winds and energetic light reshape the surrounding space.”

“These powerful forces carve out bubble-like formations and hollow cavities within the gas, clearly illustrating the effects of stellar feedback.”

“Dark clouds in the foreground glow thanks to a new star shining from behind.”

“The illuminated clouds and intricate bubbles reveal the dynamic interplay between star formation and the primordial matter from which stars arise, capturing the perpetual cycles of creation and transformation within this neighboring galaxy.”

Source: www.sci.news

Asteroid Collision Near a Nearby Star Unravels Cosmic Mystery

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Composite image of Fomalhaut’s dust belt (center hidden). The inset displays dust cloud cs1 taken in 2012 together with dust cloud cs2 from 2023.

NASA, ESA, Paul Karas/University of California, Berkeley

Around the star Fomalhaut, asteroids are involved in collisions that generate massive dust clouds. This is the first time astronomers are witnessing these events, offering insights into the early days of our solar system.

Fomalhaut has had its share of unusual findings. In 2008, Paul Kalas, based on observations from the Hubble Space Telescope in 2004 and 2005, reported a potential giant planet orbiting the young star. Over the years, however, the nature of this peculiar object, dubbed Fomalhaut b, has sparked heated debates. It could either be a planet slightly larger than Jupiter or simply a cloud of debris.

Now, Kalas and his team have revisited Fomalhaut using Hubble. “In 2023, we utilized the same equipment as before, and Fomalhaut b was undetectable. It was effectively gone,” says Kalas, “What appeared was a new Fomalhaut b.”

This new bright feature, named Fomalhaut CS2 (short for “circumstellar light source”), cannot be a planet, as it would have been identified earlier. The leading theory is that it represents a dust cloud resulting from the collision of two large asteroids or planetesimals, each approximately 60 kilometers in diameter. The disappearance of Fomalhaut b implies that it may have been a similar dust cloud all along.

“These sources exhibit noise and instability, so we’re still far from drawing definitive conclusions,” notes David Kipping at Columbia University. “Yet, all existing evidence aligns well with a broader narrative of collisions between protoplanets in nascent systems.”

Interestingly, it’s unexpected to observe such a significant break twice. “The hypothesis suggests that we shouldn’t witness such impacts more than once every 100,000 years, if not even more infrequently. And yet, for some unexplained reason, we seem to observe it twice within 20 years,” Kalas explains. “Fomalhaut lights up like a holiday tree and it’s astounding.”

This might indicate that collisions among planetesimals are occurring more frequently than previously thought, particularly around relatively young stars like Fomalhaut. Kalas and his team plan to conduct further observations over the next three years utilizing both Hubble and the more powerful James Webb Space Telescope (JWST) to track the behavior of Fomalhaut CS2 and attempt to pick up faint signals from Fomalhaut b.

This presents a rare opportunity to witness these collisions first-hand. “To comprehend these violent phenomena, we no longer need to rely solely on theoretical models; we can observe them in real time,” Kalas states. Further observations may enlighten us not only about young planetary systems generally but also about our own early solar system’s position in the cosmic landscape.

“We have long pondered whether the collisions that formed our moon are typical of what occurs throughout the universe, and now we have strong evidence suggesting they are indeed common,” Kipping remarked. “Perhaps we are not as unique as some may assume.”

Exploring the Mysteries of the Universe: Cheshire, England

Join a weekend with some of science’s brightest minds as you delve into the mysteries of the universe, featuring a tour of the renowned Lovell Telescope.

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Source: www.newscientist.com

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

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

Claude Coenen/ESA/Hubble & NASA

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

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

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

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

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

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

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

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

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

Scientific Progress DOI: 10.1126/sciadv.adx7892

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Source: www.newscientist.com

Astronomers Reveal Aging Stars Could Be Devouring Nearby Giant Exoplanets

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During the concluding phase of their main sequence life, stars with mass comparable to the Sun experience a transformative evolution. This evolutionary process is likely to affect the surrounding planetary systems. As the star expands in its post-main-sequence stage, astronomers anticipate that most exoplanets detected to date may be engulfed by the growing star.

An artist’s impression of a sun-like star engulfing a giant exoplanet. Image credits: International Gemini Observatory / NOIRLab / NSF / AURA / M. Garlick / M. Zamani

Utilizing data from NASA’s Transiting Exoplanet Survey Satellite (TESS), astronomers Edward Bryant and Vincent Van Eylen studied 456,941 stars that have just commenced their post-main sequence phase.

By employing a computer algorithm, they targeted giant planets with short orbital periods (those that complete an orbit in less than 12 days) and searched for consistent dips in brightness that would indicate these planets transiting in front of their host stars.

They discovered 130 planets and planet candidates, including 33 previously unknown, closely orbiting these stars.

The researchers observed that such planets are less likely to exist around stars that have expanded and cooled sufficiently to be categorized as red giants (more evolved stars), implying that many of these planets might have already been destroyed.

Dr. Bryant, an astronomer at University College London and the University of Warwick, stated: “This provides compelling evidence that as stars progress beyond the main sequence, planets can rapidly spiral out of existence.”

“This topic has been debated and theorized for some time, but we can now observe this phenomenon directly and quantify it at the level of stellar populations.”

“We expected to observe this phenomenon, but we were still astonished by how effectively these stars can consume nearby planets.”

“This destruction is believed to stem from a gravitational tug-of-war between the planet and the star, known as tidal interactions.”

“As the star evolves and expands, these interactions intensify.”

“Just as the moon influences the Earth’s oceans, creating tides, planets also exert a pull on their stars.”

“These interactions decelerate the planet, reducing its orbit and causing it to spiral inward, ultimately resulting in its disintegration or absorption by the star.”

“In the coming billions of years, our sun will expand and transform into a red giant,” mentioned Dr. Van Eylen, an astronomer at University College London.

“Will the planets in our solar system endure this transformation? Our findings suggest that, in some instances, planets do not survive.”

“Earth may be better off than the giant planets much closer to the stars we examine.”

“However, we only analyzed the initial part of the post-main-sequence phase, spanning the first one or two million years. There is still ample opportunity for stellar evolution.”

“Unlike the giant planets lost in our investigation, Earth has the potential to endure the Sun’s red giant phase. However, life on Earth is likely to be extinguished.”

The team’s paper was published on October 15, 2025, in Royal Astronomical Society Monthly Notices.

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Edward M. Bryant and Vincent Van Eylen. 2025. Determine the impact of post-main sequence stellar evolution on the population of passing giant planets. MNRAS 544 (1): 1186-1214; doi: 10.1093/mnras/staf1771

Source: www.sci.news

Astronomers Discover Unexpectedly Large Black Hole in Nearby Diminutive Galaxy

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Remarkably, Segue 1, an extremely faint dwarf galaxy, is positioned at the center of this image.

CDS, Strasbourg, France/CDS/Aladdin

Astoundingly, a supermassive black hole appears to reside at the heart of a nearby galaxy previously believed to be dominated by dark matter. Segue 1 is scarcely a galaxy, hosting merely around 1,000 stars compared to the Milky Way’s vast hundreds of billions. Yet, it seemingly contains a black hole with a mass approximately 10 times greater than the combined total of all its stars.

Segue 1 and similar dwarf galaxies lack sufficient stars to generate the gravitational force needed to hold them intact. To address this anomaly, physicists have long speculated that dark matter—a mysterious, invisible substance—fills the universe, contributing additional gravity.

Recently, Nathaniel Lujan and colleagues at the University of Texas at San Antonio began exploring computer models of Segue 1. They anticipated that the model yielding the best fit would be one characterized by dark matter. “After running hundreds of thousands of models, we were unable to find a viable solution,” Lujan remarks. “Eventually, we decided to experiment with the black hole mass, and that dramatically changed the results.”

The model that closely aligned with the observations of Segue 1 featured a black hole with a mass around 450,000 times that of the Sun. This discovery was particularly unexpected—not only due to the galaxy’s scarcity of stars but also considering its age. With so few stars, Segue 1 is estimated to have formed merely 400 million years following the universe’s initial star formation. Time constraints make it challenging for such a massive black hole to develop, especially since the much larger Milky Way likely consumed most of the gas that could have nourished Segue 1 shortly after its inception.

“This suggests there may be far more supermassive black holes than previously assumed,” Lujan states. If true, this could clarify some of the gravitational effects formerly attributed to dark matter, though it remains uncertain whether Segue 1 is typical of all dwarf galaxies. The quest for additional supermassive black holes continues.

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Source: www.newscientist.com

Astronomers Capture Direct Images of Brown Dwarfs Orbiting Nearby Red Dwarfs

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Astronomers utilized the Subaru Telescope, W.M. Keck Observatory, and ESA’s Gaia mission to capture images of the brown dwarf companion orbiting the M dwarf star LSPM J1446+4633.

NIRC2 image of J1446 taken in August 2023. The white arrow indicates the location of the new companion J1446B. Image provided by: Uyama et al., doi: 10.3847/1538-3881/ae08b6.

LSPM J1446+4633 (J1446) is a nearby mid-M dwarf, situated 17 parsecs (55 light-years) away.

The newly identified brown dwarf orbits its parent star at a distance approximately 4.3 times that of the Earth from the sun, completing an orbit every 20 years.

This object, designated J1446B, has a mass ranging from 20 to 60 times that of Jupiter.

“The success of this discovery was due to the combination of three complementary observational methods: (i) radial velocity (RV) measurements via long-term infrared spectroscopic monitoring by Subaru’s IRD instrument, (ii) high-resolution near-infrared imaging with advanced adaptive optics at the W.M. Keck Observatory, and (iii) precise astronomical acceleration measurements from ESA’s Gaia mission,” stated California State University astronomer Taichi Uyama and his team.

“By integrating these datasets and applying Kepler’s laws, we were able to determine the dynamic mass and orbital parameters of J1446B with unprecedented precision.”

“Radial velocity data by itself cannot differentiate between mass and orbital inclination, but the addition of direct imaging and Gaia data resolves this ambiguity.”

“The Subaru IRD-SSP program provided crucial RV data, while Keck’s cutting-edge adaptive optics allowed for the direct detection of the companion star at very close distances from the host star.”

“Previous studies have shown that astronomical acceleration from Hipparcos and Gaia can be combined with direct imaging to detect and analyze companion objects.”

“However, Hipparcos was unable to measure faint red dwarf stars like J1446.”

“Our study is the first to apply Gaia-only acceleration data to such a system, successfully constraining the orbit and dynamical mass of a brown dwarf companion.”

Near-infrared observations of J1446B indicated a brightness variation of about 30%, hinting at dynamic atmospheric phenomena such as clouds or storms.

“This finding serves as a significant benchmark for testing brown dwarf formation theories and atmospheric models,” the astronomers noted.

“Future spectroscopic studies may enable researchers to map the weather patterns on this intriguing object.”

“This achievement highlights the efficacy of combining ground-based and space-based observatories in discovering hidden worlds beyond our solar system.”

The team’s paper was published in Astronomy Magazine.

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Taichi Uyama et al. 2025. Direct Image Exploration for Companions with Subaru/IRD Strategic Program II. A brown dwarf companion star was discovered around the nearby medium-M dwarf LSPM J1446+4633. A.J. 170, 272; doi: 10.3847/1538-3881/ae08b6

Source: www.sci.news

Billions of Phones Capable of Detecting and Alerting Users to Nearby Earthquakes

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Advanced warnings can save lives before an earthquake, such as the 5.6 magnitude tremor that affected hundreds of people in Indonesia in 2022

Aditya Aji/AFP via Getty Images

Your mobile device might already be part of the billions of gadgets worldwide functioning as an early warning system for earthquakes across numerous nations.

Launched in 2020, Google’s Android Earthquake Alerts System has expanded to reach 2.3 billion Android phone and smartwatch users, enabling them to receive alerts about seismic activity, according to a recent study by Google researchers. However, these devices do more than just issue warnings; they also contribute to earthquake detection.

“Billions of Android devices come together to form mini-seismometers, establishing the world’s largest earthquake detection network,” states Richard Allen, a visiting researcher at the University of California, Berkeley.

Developed by Allen and his team, the system analyzes vibrations captured by accelerometers in Android devices and smartwatches. This collective network of sensors can determine the magnitude of an earthquake and identify which users are in close range of danger for timely warning messages.

Google’s system alerts users when it detects tremors of 4.5 or greater on the Richter scale. Yet, Allen notes that the system “may not detect all earthquakes” due to the need for sufficient nearby devices. For instance, earthquakes from most central ridges may go undetected, but the system can identify seismic events occurring up to hundreds of kilometers offshore.

A critical challenge is the swift and accurate assessment of each earthquake’s magnitude. Researchers have refined the detection algorithm over time by creating regional models that better represent local structural movements and by considering the varying sensitivities of different Android devices.

According to Allen, Google’s global system is now as effective as the ShakeAlert system, which serves the US West Coast, as well as Japan’s early warning system. He emphasizes that Google’s initiative is intended to complement, not replace, seismometer-based services, which provide warnings like ShakeAlert to West Coast residents. “Many earthquake-prone areas lack the local seismic network necessary for timely alerts,” Allen comments.

Google’s system serves as a “unique source” for nations without an existing earthquake early warning framework, states Katsu Goda from Western University in Canada, who is not affiliated with the project. He noted that even in regions with existing alert systems, Google’s solution reaches a broader audience.

The system currently delivers alerts to 98 countries and territories, including the United States, but excluding the UK. “Our focus has primarily been on countries at high historical risk for earthquakes that lack existing early warning solutions,” explains Marc Stogaitis from Google.

Android devices in the region captured seismic waves during the 6.2 magnitude earthquake in Turkey in April 2025

Data SIO, NOAA, US NAVY, NGA, GEBCO, LDEO-COLUMBIA, NSF, Landsat/Copernicus, Google Earth

A recent study evaluating system performance and accuracy revealed that the system generated alerts for 1,279 earthquake events up until March 2024, with only three false alarms. Of these, two were due to thunderstorms and one stemmed from an unrelated mass notification that caused several phones to vibrate. The research team improved their detection algorithm to minimize these types of false alerts.

Most Android devices are automatically enrolled in a mobile phone-based seismometer network and receive alerts regarding nearby earthquakes by default, although users can modify these settings. In a Google User Survey, over one-third of participants reported receiving alerts before feeling any shaking, and most indicated that these notifications were extremely beneficial.

If users remain subscribed to alerts, they will receive two types of notifications: more urgent action alerts encouraging immediate precautions like “drop, cover, hold,” which often provide only a few seconds of advance warning, and out-of-interference alerts that share general information, allowing a brief window before a user experiences the earthquake.

“The nature of earthquakes implies that there are less warning time before strong shaking compared to weaker events,” states Stogaitis. “Nonetheless, we are continuously examining adjustments to our alert strategies to extend warning times for future earthquakes.”

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Source: www.newscientist.com

Is Earth Protected from Nearby Exploding Stars? – Sciworthy

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As a star exhausts its fuel, it succumbs to gravitational forces and collapses. When a star over eight times the mass of our sun collapses, it can result in a supernova, a tremendous explosion that releases more energy in just a few seconds than what the sun produces over 10 billion years.

During a supernova explosion, high-energy particles known as Cosmic Rays of Galaxy and a violent outpouring of electromagnetic waves, referred to as Gamma rays, are generated. These emissions are termed Ionizing radiation because they dislodge electrons from the molecules they encounter, resulting in ionization. This process can devastate everything from biomolecules like DNA to atmospheric particles like aerosol. Consequently, researchers believe that supernovae pose significant threats to nearby life forms.

While humans have not witnessed a supernova explosion close to Earth, our ancestors may have been less fortunate. A nearby supernova could eject radioactive elements encapsulated in interstellar dust grains, which can travel through the solar system and eventually reach Earth. Geologists have traced these grains in marine mud over the last 10 million years and estimate that a supernova has likely exploded within 100 parsecs of our planet in the last million years. The Earth is positioned about 8,000 parsecs from the center of the Milky Way, making these stellar explosions relatively close in cosmic terms.

Historically, scientists have speculated that nearby supernovae may have influenced animal diversity by contributing to mass extinction events over the past 500 million years. Some researchers propose that cosmic rays emitted from supernovae could potentially deplete the Earth’s ozone layer every hundred million years, exposing surface dwellers to harmful UV radiation. Others suggest that ionizing radiation can interact with aerosols to form clouds that block sunlight. However, scientists remain divided on the extent of ozone depletion, how severe a supernova’s impact could be, its effects on climate, and how catastrophic it might be for the biosphere.

Recently, researchers have revisited the potentially destructive impact of nearby supernovae using models that simulate interactions among planetary atmospheres, oceans, land, and biospheres. Earth system models employ atmospheric chemistry frameworks, such as EMAC, to capture complex processes previously overlooked, including air circulation and chemical reactions. Specifically, EMAC utilizes data from outdoor experiments conducted by CERN to calculate how ions interact with aerosol particles.

The research team modeled the Earth as it exists today, with 21% atmospheric oxygen, normal radiation levels, and an intact ozone layer. They simulated an explosion of ionizing radiation equivalent to a supernova 50 parsecs away, increasing the gamma rays in their model tenfold for a few seconds and boosting cosmic rays in the galaxy by a factor of ten per annum.

The team investigated the effects of ionizing radiation bursts on the ozone layer. Their findings confirmed that ionizing radiation strips electrons from atmospheric nitrogen and oxygen atoms, leading to the formation of highly reactive molecules known as radicals, which can destroy ozone. However, they discovered that certain reactions occurred at slower rates than anticipated, resulting in less ozone depletion than expected. They also found that ionizing radiation interacts with water vapor to produce hydroxyl radicals, which, when combined with nitrogen radicals, actually contribute to ozone formation.

Based on their findings, the team estimated that supernovae could potentially deplete up to 10% of Earth’s ozone layer. This level of ozone loss is comparable to the 6% depletion caused by human-made fluorocarbons and is far from lethal. They repeated the model to account for an Earth with just 2% atmospheric oxygen, simulating conditions around 500 million years ago when life transitioned to land. This modeling revealed repeated UV protection in the ocean, and they found that at this reduced oxygen concentration, only 10% to 25% of the ozone layer was lost.

The team then analyzed how radiation from the supernova influences cloud formation and climate. They calculated that ionizing radiation could increase the number of cloud-forming particles by about 10% to 20% globally. This alteration is quite similar in magnitude to recent anthropogenic warming and could cool the Earth by approximately 2.5 watts per square meter. While they acknowledged that these changes might disturb the environment, they believe it wouldn’t lead to sudden extinction.

The researchers concluded that radiation from nearby supernovae is unlikely to trigger mass extinction events on Earth. Since our early ancestors first emerged, the atmosphere has functioned as a protective barrier, safeguarding us from immediate harmful effects. Nevertheless, they cautioned that their model does not account for the risks associated with long-term exposure to elevated levels of ionizing radiation, which remains largely unexplored. They suggested that future research should seek safe methods to investigate the direct impacts of cosmic radiation on humans and animals.


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Source: sciworthy.com

A nearby supernova explosion could have triggered multiple mass extinctions on Earth

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New research from Keele University and Universidad de Alicante shows that near Earth explosion Giant O and B type stars It occurs at a rate of 2.5 per billion years. This result supports the view that such an event may have caused one or more of the mass extinction events recorded on Earth.

Among the puppies in the constellation, I have the impression of the artist Zeta Puppis, an O-shaped star about 1,400 light years away. Image credit: Tahina Ramiaramanantsoa.

Astronomers at Kiel and Alicante University believe that the explosion of supernova near Earth could condemn both the late Devonian and Ordovician extinction events that occurred 372 and 445 million years ago, respectively.

Ordovician extinction killed 60% of marine invertebrates when life was largely confined to the ocean, and the late Devonian wiped out about 70% of all species, leading to a major change in the species of fish present in ancient seas and lakes.

Previous studies have not been able to identify a clear cause of either event, but are thought to be related to Earth's ozone layer depletion, which may have been caused by supernova.

A new study found that the velocity supernova that occurs near our planet coincides with the timing of both mass extinctions.

“Supernova explosions bring heavy chemical elements to interstellar media, which are used to form new stars and planets,” said Dr. Alexis Quintana, PhD from Kiel University, the lead author of the study.

“However, if planets, including Earth, are too close to events of this type, this can have devastating effects.”

“Supernova explosions are some of the most energetic explosions in the universe,” said Dr. Nick Wright, PhD from Keel University.

“If a large star explodes as a supernova close to Earth, the results will be devastating for life on Earth. This study suggests that this may already be happening.”

An artist impression of HR 6819, a close binary consisting of deleted B-shaped stars (background) and rapidly rotating BE stars (foreground). Image credit: ESO/L. Calsada.

Astronomers came to their conclusion after conducting a large-scale census of OB stars in the sun of Kiloparscheck (approximately 3,260 light years).

They studied the distribution of these stars to learn more about how clusters of stars and galaxies form using themselves as benchmarks, and the rate at which these stars form in our galaxies.

The census allowed researchers to calculate the rate at which supernovas occur within galaxies, which are important for supernova observations, and the rates that are important for the production of large-scale star rests, such as black holes and neutron stars throughout the universe.

Data will also help in the future development of gravitational wave detectors, a useful tool for scientists studying the structure and origin of the universe.

As part of this, the researchers calculated the supernova rate within the 20 parsecs (65 light years) of the Sun and compared this to the approximate velocity rate of mass extinction events on Earth that were previously attributed to nearby supernovas.

This exclusion events linked to other factors such as asteroid impacts and ice ages.

Comparing these datasets, experts found that their studies support the theory that supernova explosions are responsible for both the late Devonian and Ordovician extinction events.

“We calculated the supernova rate close to Earth, and we found that it coincides with the speed of mass extinction events on our planet, which are related to external forces such as supernova,” Dr. Wright said.

Astronomers believe it occurs in galaxies like the Milky Way at about one or two supernovas, or even lower speeds, but the good news is that there are only two nearby stars that can reach the supernova within the next million years or so.

“But both of these are over 500 light years from the US, and computer simulations have previously suggested that supernovaes at distance from Earth are likely to not affect our planet,” the author said.

Their study It will be published in Monthly Notices from the Royal Astronomical Society.

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Alexis L. Quintana et al. 2025. Census of AB stars within 1 kpc and collapse rate of star formation and core collapse Supernova rate. mnrasin press; arxiv: 2503.08286v1

Source: www.sci.news

Ionizing radiation from nearby supernovae impacted the evolution of the virus 2.5 million years ago

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This supernova event may have occurred at the Upper Centaurus Lupus Society. This is a group of giant stars about 457 light years away from Earth.

Illustration of an exoplanet like Earth after X-ray radiation exposure. Image credit: NASA/CXC/M. Weiss.

Life on Earth is constantly evolving under continuous exposure to ionizing radiation from both terrestrial and cosmic origins.

The radioactivity in the bedrock gradually decreases over timescales of billions of years, but the level of cosmic radiation fluctuates as the solar system moves through the Milky Way.

Nearby supernova activity could increase the level of radiation on the Earth’s surface by several orders of magnitude, which is expected to have a major impact on the evolution of life.

In particular, radiation levels improve as the solar system passes near a large group of stars known as the OB Association.

The winds associated with these large star factories are expected to inflate the super bubbles of high temperature plasma first. This could be the birthplace of most of the Core Collapse explosions taking place within the AB Association.

The solar system entered such a super bubble, commonly known as the local bubble, about 6 million years ago, and is now close to its centre.

“The Earth entered the local bubble and passed its stardust-rich appearance about 6.5 million years ago, sowing the planet with old iron 60, the radioactive iron of iron produced by the exploding stars. did it,” astronomer Santa Cruz, and colleagues at the University of California.

“Then, 20-3 million years ago, one of our neighboring stars exploded with incredible force, providing another cohort of radioactive iron to the planet.”

When Nojiri and her co-authors simulated what the supernova looked like, they discovered that it hammered the Earth with cosmic rays for 100,000 years of explosion.

This model perfectly described previously recorded spikes of radiation that shocked the Earth around that time.

“We’ve seen from other papers that radiation can damage DNA,” Nojiri said.

“It could be an evolutionary change in the cell or an accelerated mutation.”

Meanwhile, the author came across research into viral diversity in one of the Rift Valley Lakes in Africa.

“I can’t say they’re connected, but there are similar time frames,” Nojiri said.

“We found it interesting that the virus’s diversification is increasing.”

study It was published in Astrophysics Journal Letter.

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Caitlyn Nojiri et al. 2025. Bubble Life: How nearby supernova left short-lived marks on the cosmic ray spectrum, leaving an indelible trace of life. apjl 979, L18; doi: 10.3847/2041-8213/ADA27A

Source: www.sci.news

Astronomers Confirm Existence of Three Exoplanets Orbiting Nearby Solar-Type Stars.

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G-Dwarf is one of these outside planets, HD 20794D, which is likely to be a rocky planet where the parent’s star can live. HD 20794。

This image shows a resident zone around HD 20794 (green) and three planets in the system. Image credit: Gabrielpérezdíaz / smm / IAC.

“HD 20794 is not a normal star in HD 20794D,” said UNIGE ASTRONOMER XAVIER DUMUSQUE.

“Due to its lightness and proximity, it becomes an ideal candidate for the future telescope, and its mission is to directly observe the atmosphere of the outside planet.”

The HD 20794 is a bright G6V star in 6.04 % (19.7 light year) on the constellation of Ellidanus.

Stars, also known as LHS 19 or ERI, host at least three large -scale outside planets: HD 20794B, C, and D.

They have a track period of 18.3, 89.7, and 647.6 days, along with 2.2, 3, and 5.8 global quality.

“The interest of Super Earth Planet The HD 20794D is located in a zone where the stars can live and the place where liquid water can exist.

“Instead of tracing a relatively circular orbit like the Earth or Mars, the HD 20794D trains an elliptical trajectory with a large change in the distance to the star during the revolution.”

“Therefore, the planet vibrates between the inner ends of the star -free zone (0.75 au) and the track (2 au).”

“If there is water in the HD 20794D, it will promote the appearance of life from ice state to liquid state during the Earth revolution around the stars.”

Astronomer monitored the HD 20794 system with the ESO’s very large telescope (VLT) in the paranal of Chile, the Echelle branch device of the rocky planet and the stable spectrum observation (espresso) device.

They participated in espresso data along with the data of the high -precision radial speed planetary searcher (HARPS) device installed in the 3.6 -meter telescope of Chile, including archive data and new measurements from recent archives and new measurements.

“The HD 20794 system is a high -priority target for future air characteristics evaluation with direct imaging facilities,” said researchers.

Their paper Published in the journal Astronomy and astronomical physics。

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N. Nari et al。 2025. Review of nearby star HD 20794 multi -planet system A & A 693, A297; DOI: 10.1051/0004-6361/202451769

Source: www.sci.news

Study suggests that nearby rivers are causing Mount Everest’s peak to rise

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Mount Everest, also known as Chomolangma in Tibetan and Sagarmatha in Nepali, is about 15 to 50 meters higher than its original height due to uplift caused by erosion of nearby river canyons, and therefore continues to grow. This is revealed in a new study.

Han et al. They found that erosion from a network of rivers about 75 km from Everest had carved out a significant canyon. This landmass loss has caused mountains to rise by 2 mm per year, and their heights have already increased by 15 to 50 meters over the past 89,000 years. Image credit: truthseeker08.

The Himalayas, formed by the subduction of the Indian tectonic plate beneath the Eurasian plate, are home to some of the highest mountains on Earth.

Mount Everest is 8,849 meters above sea level, about 250 meters higher than the other highest peaks in the Himalayas.

Previous analysis of GPS data suggests that Everest's recent uplift is about 2 mm per year, which exceeds the expected uplift rate for the mountain range and suggests that mechanisms other than ongoing regional tectonics are responsible. This suggests that it may contribute to this process.

“Mount Everest is a remarkable mountain of myth and legend, and it continues to grow,” said Dr. Student Adam Smith.

“Our research shows that the nearby river system is cutting deeper and the loss of material is causing the mountain to spring further upwards.”

In this study, Smith and his colleagues investigated whether changes in rivers near the mountain may have contributed to Everest's recent uplift.

They used a numerical model to simulate the evolution of the Kosi river network and compared it to existing landforms.

These models suggest that the Arun River, a major tributary of the Kosi River, was involved in the occupation of another river 89,000 years ago.

The diversion of river water accelerated river erosion as the river adapted to its new path, resulting in the formation of the deep Arun River Gorge.

“Currently, the Arun River flows east of Mount Everest and joins the larger Kosi River system downstream,” Mr Smith said.

“For thousands of years, the River Arun has carved great gorges along its banks, washing away billions of tonnes of soil and sediment.”

“There are interesting river systems in the Everest region,” said Dr. Jing Geng Dai, a researcher at the China University of Geosciences.

“The upper Arun River flows eastward through highlands with flat valleys.''

“Then it suddenly turns south as the Kosi River, dropping in elevation and becoming steeper.”

“This unique feature of instability may be related to Everest's extreme height.”

The authors conclude that although erosion would have lowered local elevations along the river channel, the formation of the canyon removed the eroded mass relatively abruptly, allowing the surrounding landforms, including Everest, to compensate with surface uplift. It is argued that there is a possibility that

Although its contribution may be small compared to tectonic deformation, fluvial capture may play a role in both erosion and uplift of high landforms.

“Everest and its neighboring mountains are growing because isotropic rebound is causing them to rise faster than erosional wear,” said Dr. Matthew Fox, a researcher at University College London. said.

“Using GPS equipment, we can see it grow by about two millimeters every year. Now we can better understand what's causing that.”

“The change in the height of Mount Everest really highlights the dynamic nature of the Earth's surface,” says Dr. Xu Han, a researcher at the China University of Geosciences.

“The interaction between the erosion of the Arun River and the upward pressure of the Earth's mantle gives Everest a boost, pushing it higher than normal.”

of study Published in a magazine natural earth science.

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X Han others. The recent uplift of Chomolungma was reinforced by river drainage piracy. nut. earth sciencepublished online on September 30, 2024. doi: 10.1038/s41561-024-01535-w

Source: www.sci.news

Telegram removes ‘People Nearby’ feature and reinforces moderation policies

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Telegram’s CEO, Pavel Durov, has announced plans to enhance moderation on the messaging app and remove features that have been misused for illegal activities. Durov made these changes following his recent arrest by French authorities.

In a post on X, he stated that the goal is to shift Telegram’s moderation from criticism to praise. The changes include replacing the “People Nearby” feature with “Nearby Businesses” and disabling media uploads to Telegraph, the app’s blogging tool.

Furthermore, Durov shared that Telegram has removed references to private chats being protected and that moderation requests for those chats will not be processed. He emphasized that despite these changes, no alterations have been made to the app’s source code.

Durov acknowledged that a minority of Telegram’s 1 billion users have engaged in criminal activities, and these actions have negatively impacted the platform’s reputation. He also mentioned that Telegram now has 10 million paid subscribers.

Following his arrest, Durov addressed the situation on his Telegram channel and criticized the allegations that the app fosters anarchy. He highlighted the surprising nature of the French investigation and noted that authorities had access to communication channels with Telegram’s representatives.

Despite being released on bail, Durov faces challenges from Moscow officials who claim that France is pressuring him to disclose the app’s encryption keys to Western intelligence agencies. Russian diplomats offered assistance to Durov, but he declined their support.

The arrest has strained relations between Russia and France, with President Putin calling the actions against Durov “selective” and expressing limited contact with the Telegram founder over the years.

Source: www.theguardian.com

Astronomers find parallel jets and disks around nearby multiple star system

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Astronomers Atacama Large Millimeter/Submillimeter Array (ALMA) Mid-infrared measuring instrument (mm) NASA/ESA/CSA James Webb Space Telescope A twin disk and parallel jets were discovered in the young star system WL20.

Barsoni othersTwin disks and jets erupting from a pair of young stars in WL20. Image credit: NSF / NRAO / B. Saxton / NASA / JPL-Caltech / Harvard-Smithsonian CfA.

WL20 It is located in the Rho Ophiuchus Molecular Cloud Complex, more than 400 light years from Earth.

“What we found was absolutely surprising,” said Dr Mary Barthony, lead author of the study.

“We've known about the WL20 system for some time, but what caught our attention was that one of the stars in the system appeared to be much younger than the others.”

“Using MIRI and ALMA together, we were able to see that this one star is actually two stars next to each other.”

“Each of these stars was surrounded by a disk, and each disk emitted a jet parallel to the others.”

ALMA and Webb's MIRI observe very different parts of the electromagnetic spectrum.

Used together, they allowed astronomers to discover these hidden twins in the stellar system's radio and infrared wavelengths: ALMA found the disk, and MIRI found the jet.

They analyzed archived ALMA data to reveal the composition of the disk, and MIRI data to reveal the chemical composition of the jet.

They also analyzed high-resolution images, revealing the size of the massive disk – about 100 times the distance between Earth and the Sun.

“Without MIRI we would never have known these jets even existed, which is amazing,” Dr Barthony said.

“ALMA's high-resolution observations of the disks surrounding the two newly observed stars reveal the structure of the disks.”

“Someone looking at this ALMA data and not knowing there are twin jets would think it's a big edge-on disk with a hole in the middle, rather than two edge-on disks and two jets. That's pretty remarkable.”

Combining multi-wavelength data from ALMA and Webb revealed the complex processes involved in the formation of several stellar systems.

“We plan to take advantage of ALMA's future upgrades, such as the broadband sensitivity upgrade, to continue unlocking the mysteries surrounding the birth of stars and planetary systems,” the researchers said.

They are, result in 244th Meeting of the American Astronomical Society In Madison, Wisconsin.

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Mary Barthony others2024. Twin jets and twin discs: JWST MIRI and ALMA discoveries in the young WL20 multiple star system. 224 AustraliaAbstract #253

Source: www.sci.news

ALMA discovers over 100 different molecules in a nearby starburst galaxy

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Astronomers using the Atacama Large Millimeter/Submillimeter Array (ALMA) have detected more than 100 molecular species at the center of starburst galaxy NGC 253. This is far more than anything previously observed in galaxies outside the Milky Way.

Artist's impression of the center of starburst galaxy NGC 253. Image credit: NRAO/AUI/NSF.

In the Universe, some galaxies form stars much faster than our Milky Way. These galaxies are called starburst galaxies.

Exactly how such extremely prolific star formation occurs and how it ends is still a mystery.

The probability of star formation is determined by the properties of the raw material from which stars are formed, such as molecular gas, which is a gaseous substance made up of various molecules.

For example, stars form in dense regions within molecular clouds where gravity can work more effectively.

Some time after a star has been actively forming, explosions from existing or dead stars can energize the surrounding material and prevent future star formation.

These physical processes affect the galaxy's chemistry and imprint signatures on the strength of the signals from its molecules.

Because each molecule emits light at a specific frequency, observations over a wide frequency range can analyze its physical properties and provide insight into the mechanism of starbursts.

It was observed by Dr. Nanase Harada of the National Astronomical Observatory of Japan as part of the ALMA Comprehensive High-Resolution Extragalactic Molecular Inventory (ALCHEMI). NGC253 a starburst galaxy located 11.5 million light-years away in the constellation Corina.

They were able to detect more than 100 molecular species in the galaxy's central molecular belt.

This chemical raw material is most abundantly found outside the Milky Way, and includes molecules such as ethanol and the phosphorus-containing species PN, which were first detected beyond the Milky Way.

First, astronomers found that the dense molecular gas likely fuels active star formation in this galaxy.

Each molecule emits at multiple frequencies, and its relative and absolute signal strength varies with density and temperature.

Analysis of numerous signals from several molecular species revealed that the amount of dense gas at the center of NGC 253 is more than 10 times greater than the amount of gas at the center of the Milky Way. This could explain why NGC 253 forms about 30 stars. With the same amount of molecular gas, you can get many times more efficiency.

One mechanism by which molecular clouds compress and become denser is through collisions between them.

At the center of NGC 253, cloud collisions occur where gas streams and stars intersect, creating shock waves that travel at supersonic speeds.

These shock waves vaporize molecules such as methanol and HNCO and freeze them onto ice dust particles.

Once the molecules evaporate as a gas, they can be observed with radio telescopes such as ALMA.

Certain molecules also track ongoing star formation. It is known that complex organic molecules exist in abundance around young stars.

Schematic image of the center of NGC 253. Spectra from the ALCHEMI survey are shown where different tracer species are enriched.Image credits: ALMA / ESO / National Astronomical Observatory of Japan / NRAO / Harada other.

The study suggests that in NGC 253, active star formation creates a hot, dense environment similar to that found around individual protostars in the Milky Way.

The amount of complex organic molecules at the center of NGC 253 is similar to that found around galactic protostars.

In addition to the physical conditions that can promote star formation, the study also uncovered harsh environments left behind by previous generations of stars that could slow the formation of future stars.

When a massive star dies, a massive explosion known as a supernova occurs, releasing energetic particles called cosmic rays.

Molecular composition of NGC 253 revealed by enhancement of species such as H3○+ and HOC+ Molecules in this region are stripped of some of their electrons by cosmic rays at least 1,000 times faster than molecules near the solar system.

This suggests that there is a significant energy input from the supernova, making it difficult for the gas to condense and form a star.

Finally, the ALCHEMI survey provided an atlas of 44 molecular species, double the number obtained in previous studies outside the Milky Way.

By applying machine learning techniques to this atlas, the researchers were able to identify which molecules can most effectively track the star formation story described above from beginning to end.

As explained above with some examples, certain molecular species track phenomena such as shock waves and dense gas that can help star formation.

Young star-forming regions are rich in chemicals, including complex organic molecules.

On the other hand, the developed starbursts show an enhancement of cyanogen radicals, which indicate an energy output in the form of ultraviolet photons from massive stars, which could also hinder future star formation.

“Finding these tracers may help plan future observations to take advantage of the broadband sensitivity improvements expected over this decade as part of the ALMA 2030 development roadmap. “Simultaneous observation of molecular transitions will become more manageable,” the scientists said.

Their paper will appear in Astrophysical Journal Appendix Series.

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Nanase Harada other. 2024. ALCHEMI Atlas: Principal component analysis reveals starburst evolution of NGC 253. APJS 271, 38; doi: 10.3847/1538-4365/ad1937

Source: www.sci.news

Organic Farms Impact Pesticide Usage on Nearby Conventional Farms

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On organic farms, conventional farming practices appear to inadvertently cause more pesticides to be used in surrounding fields

Daniel Balderas/Shutterstock

Organic farmers dedicate their working lives to producing food with minimal use of pesticides, but by curbing the use of chemicals on their land, they can unknowingly damage their neighbor’s fence. may be causing a sharp increase in pesticide use.

Ashley Larsen and colleagues from the University of California, Santa Barbara, evaluated land use and pesticide data across 14,000 fields in Kern County, California. It is one of the largest agricultural counties in the state, producing agricultural products such as almonds, grapes, carrots, and pistachios.

The researchers found that when organic farmland is surrounded by conventional agriculture, neighboring farmers appear to increase their use of pesticides, which is associated with a 10 percent increase in organic farmland. Total pesticide use in conventional fields increases by 0.3%. Most of that is due to increased use of pesticides, the researchers found.

This is because more insects, pests or not, are present on organic land and tend to ‘bleed-off’ onto adjacent conventional farmland, leading these farmers to increase their use of pesticides. It is considered. “Pests come and sow the seeds for new outbreaks. [farmers] We will increase the use of pesticides,” Larsen told reporters at a press conference. This effect appears to be strongest when the adjacent field is within 2.5 kilometers of the organic “focal field”.

Conversely, the researchers found that the presence of organic fields was associated with reduced pesticide use in adjacent organic fields, with a 10 percent increase in the area of surrounding organic fields reducing total pesticide use on organic fields by 3%. He pointed out that it is associated with a decrease in the percentage of organic focal field. This may be because larger areas of organic farmland allow for larger and more stable communities of beneficial insects.

Organic agriculture only covers about 2 percent of the world’s land, but in Kern County, about 5.5 percent of the farmed area is organic.

If organic farming occupies a high proportion of agricultural land, perhaps Researchers say that regardless of where organic fields are located, net pesticide use is reduced by more than 20 percent.

However, when relatively small areas of organic cropland are evenly distributed across the landscape, such as in Kern County, net pesticide use may actually be higher than if no organic cropland were present.

“Our simulations suggest that low levels of organic agriculture in the landscape may actually increase net pesticide use,” Larsen said.

However, she said this impact can be completely mitigated by clustering organic farmland to minimize potential pest spillover. “Basically, at the policy level, how do we encourage the spatial clustering of new organic fields to take advantage of the pest control benefits of organic and limit the potential costs of organic to conventional growers?” It might be worth considering.

This could include paying subsidies to farmers to convert more land to organic farming in certain areas, or even creating buffer zones between organic and non-organic land. be.

robert finger Switzerland’s ETH Zurich said the study results demonstrate the need for policymakers to consider land use policy at a “landscape scale” to maximize the environmental benefits of organic farming. “Fundamentally, it’s not enough to think about a single field or a single farm,” he says.

topic:

Source: www.newscientist.com

Massive star ultraviolet radiation influences nearby planetary systems

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Astronomers have known for decades that the powerful light emitted by massive stars can disrupt planetary disks of dust and gas that swirl around young stars, the cradles of planetary birth. However, important questions remained unanswered. How fast does this process occur and will there be enough material left to form a planet?

NASA/ESA/CSA Using the James Webb Space Telescope and the Atacama Large Millimeter Array (ALMA), astronomers are now discovering the Orion Nebula, a nursery for stars, and specifically the protoplanetary disk named d203-506. I’m researching. Although it was confined to a small area, it exploded to an abnormally large size. This makes it possible to measure material loss rates with unprecedented precision.

bernet other. We observed the protoplanetary disk d203-506 illuminated by the far-ultraviolet rays of the Orion Nebula.Image credit: Berne other., doi: 10.1126/science.adh2861.

Young, low-mass stars are often surrounded by relatively short-lived protoplanetary disks of dust and gas, which are the raw materials for planet formation.

Therefore, the formation of gas giant planets is limited by processes that remove mass from the protoplanetary disk, such as photoevaporation.

Photoevaporation occurs when the upper layers of a protoplanetary disk are heated by X-rays or ultraviolet protons, raising the temperature of the gas and ejecting it from the system.

Because most low-mass stars form in clusters that also include high-mass stars, protoplanetary disks are expected to be exposed to external radiation and experience photoevaporation due to ultraviolet radiation.

Theoretical models predict that deep ultraviolet light creates a region of photodissociation, a region where ultraviolet photons projected from nearby massive stars strongly influence the gas chemistry on the surface of the protoplanetary disk. However, it has been difficult to observe these processes directly.

Dr. Thomas Howarth of Queen Mary University of London and his colleagues investigated the effects of ultraviolet irradiation using a combination of infrared, submillimeter wave, and optical observations of the protoplanetary disk d203-506 in the Orion Nebula using the Webb and ALMA telescopes.

By modeling the kinematics and excitation of the emission lines detected within the photodissociation region, they found that d203-506 loses mass rapidly due to heating and ionization by deep ultraviolet light.

According to the research team, the rate at which this mass is lost from d203-506 indicates that gas could be removed from the disk within a million years, suppressing the ability of gas giants to form within the system. It is said that there is.

“This is a truly exceptional case study,” said Dr Howarth, co-author of the paper. paper It was published in the magazine science.

“The results are clear: this young star is losing a staggering 20 Earth masses of material per year, suggesting that Jupiter-like planets are unlikely to form in this system.” .”

“The velocities we measured are in perfect agreement with theoretical models and give us confidence in understanding how different environments shape planet formation across the universe.”

“Unlike other known cases, this young star is exposed to only one type of ultraviolet light from a nearby massive star.”

“Because there is no 'hot cocoon' created by higher-energy ultraviolet light, the planet-forming material is larger and easier to study.”

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Olivier Verne other. 2024. Photoevaporation flow caused by far ultraviolet rays observed in a protoplanetary disk. science 383 (6686): 988-992; doi: 10.1126/science.adh2861

Source: www.sci.news

Surprising Images of Nearby Star-Forming Regions Captured by Hubble

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astronomer using NASA/ESA Hubble Space Telescope We captured a vivid image of IRAS 16562-3959, a beautiful star-forming region in the constellation Scorpius.

This Hubble image shows IRAS 16562-3959, a star-forming region about 5,900 light-years away in the constellation Scorpius. Image credits: NASA / ESA / Hubble / R. Fedriani / J. Tan.

IRAS 16562-3959The star, also known as 2MASX J16594225-4003451, is located 5,900 light-years away in the constellation Scorpius.

“At the center of the image, IRAS 16562-3959 is thought to contain a massive star with a mass approximately 30 times that of the Sun, which is still in the process of formation,” Hubble team members said in a statement. Ta.

“At the near-infrared wavelengths that Hubble detects, the central region appears dark because there is so much dust in the way.”

“Near-infrared light, however, primarily leaks out from two sides, the top left and bottom right, where powerful jets from massive protostars are removing dust.”

“The multi-wavelength images containing this amazing Hubble scene will help us better understand how the largest and brightest stars in the Milky Way are born.”

The new image of IRAS 16562-3959 was created from separate exposures taken in the near-infrared region of the spectrum. Hubble's Wide Field Camera 3 (WFC3).

Four filters were used to sample different wavelengths. Color is obtained by assigning different hues to each monochromatic image associated with an individual filter.

“A filter is a thin piece of highly specialized material that only allows light at very specific wavelengths to pass through,” the astronomer explained.

“We can slide them in front of the light-sensing part of the telescope, allowing us to control which wavelengths of light the telescope collects for each observation.”

“This is useful not only for certain scientific studies, but also for creating images like this.”

“Regardless of which filter was used, raw telescopic observations are always monochrome,” they added.

“However, specially trained artists and image professionals can choose colors that match the wavelength range covered by individual filters.”

“Alternatively, if a direct match is not possible, for example the data used in this image is all in the infrared range, to which the human eye is not sensitive, so the artist has chosen colors that are wisely representative of what they are trying to represent.” You can. It’s happening.”

“For example, shorter wavelengths might be assigned a bluer color and longer wavelengths a redder color, as is the case with the visible light range.”

“The data from multiple filters can then be combined to build multicolor images that look beautiful and have scientific meaning.”

Source: www.sci.news