Category: 7. Science

  • Chemists develop molecule for important step toward artificial photosynthesis

    Chemists develop molecule for important step toward artificial photosynthesis

    image: 

    As with natural photosynthesis, the new molecule temporarily stores two positive and two negative charges.


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    Credit: Deyanira Geisnæs Schaad

    A research team from the University of Basel, Switzerland, has developed a new molecule modeled on plant photosynthesis: under the influence of light, it stores two positive and two negative charges at the same time. The aim is to convert sunlight into carbon-neutral fuels.

    Plants use the energy of sunlight to convert CO2 into energy-rich sugar molecules. This process is called photosynthesis and is the foundation of virtually all life: animals and humans can “burn” the carbohydrates produced in this way again and use the energy stored within them. This once more produces carbon dioxide, closing the cycle.

    This model could also be the key to environmentally friendly fuels, as researchers are working on imitating natural photosynthesis and using sunlight to produce high-energy compounds: solar fuels such as hydrogen, methanol and synthetic petrol. If burned, they would produce only as much carbon dioxide as was needed to produce the fuels. In other words, they would be carbon-neutral.

    A molecule with a special structure

    In the scientific journal Nature Chemistry, Professor Oliver Wenger and his doctoral student Mathis Brändlin have now reported on an important interim step toward achieving this vision of artificial photosynthesis: they have developed a special molecule that can store four charges simultaneously under light irradiation – two positive ones and two negative ones.

    The intermediate storage of multiple charges is an important prerequisite for converting sunlight into chemical energy: the charges can be used to drive reactions – for example, to split water into hydrogen and oxygen.

    The molecule consists of five parts that are linked in a series and each performs a specific task. One side of the molecule has two parts that release electrons and are positively charged in the process. Two on the other side pick up the electrons, which causes them to become negatively charged. In the middle, the chemists placed a component that captures sunlight and starts the reaction (electron transfer).

    Two steps using light

    In order to generate the four charges, the researchers took a stepwise approach using two flashes of light. The first flash of light hits the molecule and triggers a reaction in which a positive and a negative charge are generated. These charges travel outward to the opposite ends of the molecule. With the second flash of light, the same reaction occurs again, so that the molecule then contains two positive and two negative charges.

    Works in dim light

    “This stepwise excitation makes it possible to use significantly dimmer light. As a result, we are already moving close to the intensity of sunlight,” explains Brändlin. Earlier research required extremely strong laser light, which was a far cry from the vision of artificial photosynthesis. “In addition, the charges in the molecule remain stable long enough to be used for further chemical reactions.”

    That being said, the new molecule has not yet created a functioning artificial photosynthesis system. “But we have identified and implemented an important piece of the puzzle,” says Oliver Wenger. The new findings from the study help to improve our understanding of the electron transfers that are central to artificial photosynthesis. “We hope that this will help us contribute to new prospects for a sustainable energy future,” says Wenger.

    Article Title

    Photoinduced Double Charge Accumulation in a Molecular Compound

    Article Publication Date

    25-Aug-2025

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  • Dragon supply mission docks with International Space Station

    Dragon supply mission docks with International Space Station

    Aug. 25 (UPI) — The International Space Station received more than 5,000 pounds of supplies after a SpaceX cargo spacecraft arrived there Monday.

    NASA reported in a press release that a cargo Dragon ship, serial number C211, docked with the Harmony utility hub of the ISS at 7:05 a.m. EDT as part of the 33rd Commercial Resupply Services mission, or CRS-33, after launching Sunday via a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Space Force Station in Florida.

    C211 moved in orbit for around 29 hours before docking with the ISS 25 minutes ahead of schedule and carried scientific investigation items among its consignment.

    “Commercial resupply missions to the International Space Station deliver science that helps prove technologies for Artemis lunar missions and beyond,” acting NASA Administrator Sean Duffy said in a statement.

    The ISS announced on social media Sunday that a metal 3D printer, a liver tissue bioprinter and bone-forming stem cells are among the items brought there by C211.

    “This flight will test 3D printing metal parts and bioprinting tissue in microgravity-technology that could give astronauts tools and medical support on future moon and Mars missions,” Duffy explained.

    C211 will stay docked with the ISS for around five months, during which time the Dragon ship will perform multiple engine burns to help maintain the station’s location in orbit.

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  • Hubble Space Telescope Revisits Messier 96

    Hubble Space Telescope Revisits Messier 96

    Astronomers using the NASA/ESA Hubble Space Telescope have produced a spectacularly detailed image of the asymmetric spiral galaxy Messier 96.

    This Hubble image shows Messier 96, a spiral galaxy some 34 million light-years away in the constellation of Leo. Image credit: NASA / ESA /Hubble / F. Belfiore / D. Calzetti.

    Messier 96 is a spiral galaxy located in the constellation of Leo, about 34 million light-years from Earth.

    The galaxy was first discovered by French astronomer Pierre Méchain on March 20, 1781, and added to Charles Messier’s catalogue of astronomical objects just four days later.

    Also known as NGC 3368, LEDA 32192 or M96, it spans about 100,000 light-years across — about the size of our Milky Way Galaxy — and has an estimated mass of 80 billion solar masses.

    Messier 96 is a dominant member of the Leo I galaxy group, also called the M96 group.

    The group also includes Messier 95, Messier 105 as well as a number of fainter galaxies, and is the nearest group containing both bright spiral galaxies and a bright elliptical galaxy.

    Messier 96 resembles a giant maelstrom of glowing gas, rippled with dark dust that swirls inwards towards the nucleus.

    It’s a very asymmetric galaxy; its dust and gas is unevenly spread throughout its weak spiral arms, and its core is not exactly at the galactic center.

    Its arms are also asymmetrical, thought to have been influenced by the gravitational pull of other galaxies within the Leo I group.

    “The gravitational pull of its galactic neighbors may be responsible for Messier 96’s uneven distribution of gas and dust, asymmetric spiral arms, and off-center galactic core,” the Hubble astronomers said in a statement.

    “This asymmetric appearance is on full display in a new Hubble image, which incorporates observations made in ultraviolet and optical light.”

    “Hubble images of Messier 96 have been released previously in 2015 and 2018,” they added.

    “Each successive image has added new data, building up a beautiful and scientifically valuable view of the galaxy.”

    “This third version gives an entirely new perspective on Messier 96’s star formation.”

    “The bubbles of pink gas in this image surround hot, young, massive stars, illuminating a ring of star formation in the outskirts of the galaxy.”

    “These young stars are still embedded within the clouds of gas from which they were born.”

    “The new data included for the first time in this image will be used to study how stars are born within giant dusty gas clouds, how dust filters starlight, and how stars affect their environments.”

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  • Research Leads to the Discovery of Wasp Species Previously Unknown in the U.S.

    Research Leads to the Discovery of Wasp Species Previously Unknown in the U.S.

    Newswise — A research team including faculty at Binghamton University, State University of New York have identified two previously unknown species of parasitic wasps living in the United States.A research team including facutly at Binghamton University, State University of New York have identified two previously unknown species of parasitic wasps living in the United States.

    Oak gall wasps and their predators don’t have the panache of butterflies, but they’re attracting growing interest among both scientists and naturalists.

    Only 1 to 8 millimeters long, these small insects create the tumor-like plant growths known as “galls.” Small as a pinhead or large as an apple, galls can take striking shapes, with some resembling sea urchins or saucers, explained Binghamton University Associate Professor of Biological Sciences Kirsten Prior, who also co-leads Binghamton’s Natural Global Environmental Change Center.

    And if these wasps are a mascot for anything, it’s biodiversity. North America has around 90 different species of oak trees, and around 800 species of oak gall wasps that live upon them. Parasitic wasps lay their eggs in the galls and go on to devour the entire oak gall wasp.

    But how many species of parasitoid wasps are out there? That’s a question that scientists — both academic researchers traveling the globe and everyday citizens in their own backyard — are working to answer.

    A recent article in the Journal of Hymenoptera Research, “Discovery of two Palearctic Bootanomyia Girault (Hymenoptera, Megastigmidae) parasitic wasp species introduced to North America,” gives insight into a previously unknown level of species diversity. In addition to Prior, co-authors include current graduate student Kathy Fridrich and former graduate student Dylan G. Jones, as well as Guerin Brown, Corey Lewis, Christian Weinrich, MaKella Steffensen and Andrew Forbes of the University of Iowa, and Elijah Goodwin of the Stone Barns Center for Food and Agriculture in Tarrytown, N.Y.

    This discovery is part of a larger research effort. In 2024, the National Science Foundation awarded a $305,209 grant to Binghamton University for research into the diversity of oak gall wasps and parasitoids throughout North America. The project is a collaboration between Prior, Forbes at the University of Iowa, Glen Hood at Wayne State University and Adam Kranz, one of the creators behind the website Gallformers.org, which helps people learn about and identify galls on North American plants.

    The NSF grant investigates a core question: How do gall-forming insects escape diverse and evolving clades of parasitic wasps — and how do parasites catch up? To answer that question, researchers are collecting oak gall wasps around North America and using genetic sequencing to determine which parasitic wasps emerge from the galls. Among them are Fridrich and fellow Binghamton graduate student Zachary Prete, who spent the summer on a gall- and parasitoid-collection trip from New York to Florida.

    “We are interested in how oak gall characteristics act as defenses against parasites and affect the evolutionary trajectories of both oak gall wasps and the parasites they host. The scale of this study will make it the most extensive cophylogenetic study of its kind,” Prior said. “Only when we have a large, concerted effort to search for biodiversity can we uncover surprises — like new or introduced species.”

    Discovering unknown species

    Over the past several years, researchers with Prior’s lab traveled the West Coast from California to British Columbia, collecting approximately 25 oak gall wasp species and rearing tens of thousands of parasitic wasps, which were ultimately identified as more than 100 different species.


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  • Don’t miss Mars close to the slender crescent moon at sunset on Aug. 26

    Don’t miss Mars close to the slender crescent moon at sunset on Aug. 26

    Look to the western horizon to catch a fleeting glimpse of the thin crescent moon alongside the red glow of Mars on Aug. 26, set among the stars of the constellation Virgo.

    Mars will sit less than 10 degrees above the horizon at sunset, with the 11 %-lit waxing crescent moon hanging less than 6 degrees to its lower left. Remember, the width of your clenched fist held at arm’s length accounts for 10 degrees in the night sky, while the span of your index, middle and ring fingers is approximately 5 degrees.

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  • Nitrogen Needs Could Be Limiting Nature’s Carbon Capacity

    Nitrogen Needs Could Be Limiting Nature’s Carbon Capacity

    Plants use nitrogen to produce proteins, enzymes, and chlorophyll: all necessary components to perform photosynthesis, in which plants remove carbon from the atmosphere and store it in their leaves, roots, and soil.

    However, though the atmosphere is made up of more than 78% nitrogen, the element is unusable for plants in its natural form. Tiny microorganisms called diazotrophs are responsible for “fixing” nitrogen into a form that plants can absorb and use. Diazotrophs live in the soil and in living and decaying plants, creating important partnerships with both naturally growing vegetation and agricultural crops.

    Because plants need the nitrogen to grow and remove carbon from the atmosphere, understanding the global distribution of biological nitrogen fixation (BNF) is crucial for building accurate climate models.

    But a new study makes a surprising update to global BNF estimates: Forests, grasslands, and other natural areas may have access to between a quarter and two thirds less biologically fixed nitrogen than previously thought. In previous studies, most field measurements of BNF in natural settings were taken from locations such as tropical forests, where nitrogen-fixing organisms are 17 times more abundant than the global average, creating an overestimation of nitrogen availability. This new work, coauthored by a team of 24 international scientists, examines a broader range of ecosystem types and provides a more detailed picture of the global distribution of nitrogen fixation.

    Modernized Mapping

    A group of researchers, many of whom are involved in the new study, first published a paper on how to model BNF in 1999, explained lead author Carla Reis Ely, an ecosystem ecologist at the Oak Ridge Institute for Science and Education. “But they knew that there were some issues, particularly with data on the abundance of nitrogen fixers, that needed to be addressed.”

    The scientists involved with the updated project started by reviewing a compilation of field measurements and distribution data on BNF across natural ecosystems. They found that the sampling bias in past research had produced an overestimation of global nitrogen availability.

    Reis Ely said that “it makes sense” that scientists hoping to measure BNF would do their research in places where they know BNF is occurring. “It’s very hard to propose a project where scientists were going to go to a place to measure nitrogen fixation where they know nitrogen fixation is not happening.”

    They compiled more than 1,100 existing measurements of BNF rates from natural field sites, ranging from tropical forests to the Arctic. In doing so, they aimed to build a much larger and more representative dataset on how common nitrogen-fixing organisms and their hosts (such as shrubs and mosses) are across various regions and ecosystems. Once they had gathered and organized the measurements of BNF rates from specific sites, they upscaled those rates to estimate and map global nitrogen fixation rates for each of Earth’s biomes.

    From Forests to Farms—and Beyond

    According to the study’s findings, the amount of nitrogen fixation by microbes in natural environments is approximately 25 million tons lower than previously estimated.

    According to the study’s findings, the amount of nitrogen fixation by microbes in natural environments is approximately 25 million tons lower than previously estimated—the equivalent of 113 fully loaded cargo ships. Most of it occurs in tropical forests and drylands, but Reis Ely noted that soils, biocrusts, mosses, and lichens also conduct high amounts of nitrogen fixation.

    Though naturally occurring nitrogen fixation is lower than previous estimates, agriculturally based nitrogen fixation has actually been underestimated, the researchers discovered after sorting through thousands of measurements of agricultural BNF. When natural and agricultural datasets were combined, “we found both lower natural nitrogen fixation and higher agricultural nitrogen fixation than prior estimates, [indicating] an increasing human signal on this essential process worldwide,” said Steven Perakis, an ecologist with the U.S. Geological Survey at the Forest and Rangeland Ecosystem Science Center and one of the study’s authors.

    Crops like soybeans and alfalfa host bacteria that are fixing much more nitrogen than the natural systems that they replaced were fixing. Even though agricultural nitrogen-fixing crops cover only 6% of Earth’s land, they have boosted global nitrogen fixation by 64% since preindustrial levels.

    This increase comes with pros and cons: Nitrogen-fixing crops can help feed Earth’s growing population, and they tend to be more eco-friendly than crops requiring chemical fertilizers. But too much nitrogen can upset the nutrient balance in soils and threaten biodiversity by feeding the growth of invasive plants. Further, excess nitrogen can be converted into the greenhouse gas nitrous oxide, and runoff from these soils can leach into groundwater and cause algal blooms.

    “It’s a Goldilocks sort of thing. You want just enough, but not too much, for healthy functioning of ecosystems.”

    “Less nitrogen fixation in natural areas could mean reduced capacity [for plants] to uptake carbon from the atmosphere and help mitigate climate change,” Reis Ely said. “On the other hand, if we underestimate how much agricultural nitrogen fixation is happening, we are also underestimating how much excess nitrogen we are adding to natural environments.”

    Understanding this balance has implications for estimating nitrogen needs in agriculture as well as how forests grow and store carbon as carbon dioxide levels rise. “It’s a Goldilocks sort of thing. You want just enough, but not too much, for healthy functioning of ecosystems,” said Eric Davidson, a biogeochemist at the University of Maryland Center for Environmental Science who was not involved in the study.

    With this new dataset, researchers can now update their models, which may have been under- or overestimating the nitrogen fixation occurring in natural and agricultural settings. Correct estimates can factor into plans for mitigating climate change. “Could these numbers, these global estimates, change in the future?” Davidson said. “Yes, they could with better understanding. But for the time being, it would appear that this is a significant improvement.”

    —Rebecca Owen, Science Writer (@beccapox.bsky.social)

    Citation: Owen, R. (2025), Nitrogen needs could be limiting nature’s carbon capacity, Eos, 106, https://doi.org/10.1029/2025EO250312. Published on 25 August 2025.
    Text © 2025. The authors. CC BY-NC-ND 3.0
    Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

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  • Scientists discover new ‘3D genome organizer’ linked to fertility and cancer

    A research team at Kyoto University has discovered STAG3-cohesin, a new mitotic cohesin complex that helps establish the unique DNA architecture of spermaotogonial stem cells (SSCs), the stem cells that give rise to sperm. This “DNA organizer” is crucial for sperm production in mice: without STAG3, SSCs cannot differentiate properly, leading to a fertility problem. In humans, the researchers found that STAG3 is highly expressed in immune B cells and in B-cell lymphomas (a type of blood cancer), and blocking it slowed the growth of these cells. This discovery might open the door to new strategies for treating infertility and certain cancers.

    This research is led by Prof. Mitinori Saitou, Director/Principal Investigator at the Institute for the Advanced Study of Human Biology (WPI-ASHBi), Kyoto University (also Professor at the Graduate School of Medicine), Dr. Masahiro Nagano (then Assistant Professor at the Graduate School of Medicine, currently Research Fellow at ASHBi and Postdoctoral Researcher at the Massachusetts Institute of Technology), and Dr. Bo Hu (then Ph.D. student, currently Research Fellow at ASHBi). The results of this study will be published online in Nature Structural & Molecular Biology at 10:00 am GMT (6:00 pm Japan Standard Time) on August 25, 2025.

    Background

    Our bodies contain many different types of cells, yet they all contain the same DNA. What makes each cell type unique is how this DNA is modified, packaged, folded, and organized. Think of DNA as a very long piece of string. Inside every nucleus, about two meters of this DNA string must be folded and stored in a space smaller than the width of a human hair. This folding is highly organized, with special boundaries called insulation that separate different regions of DNA and control which genes are turned on or off. Ring-shaped protein complexes called cohesins serve as the key players that create these boundaries. Cohesin complexes were previously thought to exist in two main forms: mitotic cohesins (contain STAG1 or STAG2 together with RAD21) and meiotic cohesins (contain STAG3 together with REC8 or RAD21L).

    Germ cells are unique because they pass DNA to the next generation, and they undergo major changes in DNA folding during development. These cells undergo massive reorganization of their DNA packaging during development. Notably, SSCs have a unique way of organizing their DNA with unusually weak boundaries, but scientists do not yet understand how this happens.

    Key findings

    Because cohesin complexes contribute to DNA boundaries, and SSCs are mitotically dividing cells before entering meiosis, the research team decided to map where different cohesin proteins were located in SSCs cultured in vitro, and which proteins were present at each site. They found that RAD21, which normally partners with STAG1 or STAG2 in dividing cells, was instead partnering with STAG3. This protein was previously thought to function only during meiosis. Using immunoprecipitation–mass spectrometry (a technique that identifies which proteins stick together), they confirmed that RAD21 and STAG3 form a complex, revealing a new type of cohesin, which they referred to as STAG3-cohesin.

    To find out what this new complex does, the researchers created two types of genetically modified SSCs in vitro: one set completely lacked STAG3, while the other contained only STAG3 (without STAG1 or STAG2). They discovered that STAG3-cohesin is responsible for the unusually weak DNA boundaries in SSCs. Most importantly, in mice missing STAG3, the SSCs could not progress from their stem-cell state to the next stage of sperm development in an efficient manner. This led to a fertility problem, showing that STAG3-cohesin does more than organize DNA and is critical for proper germ cell development.

    As STAG3 functions in mitotically dividing cells, the team then investigated whether it might also function in other human cell types. By analyzing large datasets of all human cell types, they found that STAG3 is highly expressed in immune B cells and in B-cell lymphomas, a type of blood cancer. Interestingly, blocking STAG3 caused these lymphoma cells to grow much more slowly in laboratory studies, suggesting that STAG3 could be explored as a possible target for future cancer research.

    Outlook

    This study has revealed STAG3-cohesin as a new type of DNA-organizing protein complex that works very differently from previously known complexes. Because of its unique properties, further research on this complex is expected to advance our understanding of how gene activity is controlled through DNA organization. One of the most striking discoveries was that simply changing STAG3 levels could alter the proportion of stem cells in the testis. This suggests a novel mechanism that regulates the SSC state at the boundary between normal cell division and the start of meiosis.

    Beyond germ cells, the discovery that blocking STAG3 slows the growth of B-cell cancers points to a possible role for STAG3 in future cancer research. Although more research is needed to uncover the precise mechanisms, these findings offer new insights that could advance stem cell biology, reproductive medicine, and cancer treatment.

     

    KYOTO, Japan – August 22, 2025

    Glossary

    • Spermatogonial stem cells (SSCs): The stem cells in the testis that self-renew and also differentiate to give rise to sperm.
    • Mitosis: The process by which a cell produces identical copies of itself, resulting in daughter cells with the same genetic information.
    • Meiosis: A specialized form of division unique to germ cells, through which sperm or eggs are generated.
    • Insulation: The “boundaries” within the 3D structure of DNA. They prevent enhancers (DNA elements that help turn genes on) from influencing genes across the boundary, effectively dividing the genome into separate functional regions.
    • B cells: Immune cells that play a central role in antibody production within the immune system.
    • Cohesin complex: A ring-shaped protein complex that holds chromatids together and helps organize DNA into loops essential for gene regulation and mitosis.

     

    ###

    About Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University

    What key biological traits make us ‘human’, and how can knowing these lead us to better cures for disease? ASHBi investigates the core concepts of human biology with a particular focus on genome regulation and disease modeling, creating a foundation of knowledge for developing innovative and unique human-centric therapies.

    About the World Premier International Research Center Initiative (WPI)

    The WPI program was launched in 2007 by Japan’s Ministry of Education, Culture, Sports, Science and Technology (MEXT) to foster globally visible research centers boasting the highest standards and outstanding research environments. Numbering more than a dozen and operating at institutions throughout the country, these centers are given a high degree of autonomy, allowing them to engage in innovative modes of management and research. The program is administered by the Japan Society for the Promotion of Science (JSPS).  

    Journal

    Nature Structural & Molecular Biology

    Method of Research

    Experimental study

    Subject of Research

    Cells

    Article Title

    The mitotic STAG3–cohesin complex shapes male germline nucleome

    Article Publication Date

    25-Aug-2025

    Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

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  • Radio dish on the move photo of the day for Aug. 25, 2025

    Radio dish on the move photo of the day for Aug. 25, 2025

    To peer deep into space, observatories like the Atacama Large Millimeter/submillimeter Array (ALMA) use radio dishes to study cosmic structures at radio wavelengths. But sometimes, to get a better view, these radio dishes need to be rearranged and moved.

    This is no small feat, as according to ALMA, the radio dishes weigh up to 100 tons (90,718 kg).

    What is it?

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  • Flash From Nearby Galaxy Brightest of Its Kind Ever Seen : ScienceAlert

    Flash From Nearby Galaxy Brightest of Its Kind Ever Seen : ScienceAlert

    A dazzling bolt of radio light from across intergalactic space is the most powerful of its kind seen to date – and its location has been tracked with unprecedented precision.

    On 16 March 2025, the CHIME radio telescope in Canada recorded a one-off fast radio burst ( FRB) so powerful, astronomers initially weren’t sure about what they were looking at – discharging in mere milliseconds as much energy as the output of the Sun over four days.

    It has been named the RBFLOAT, or radio-brightest flash of all time.

    Related: Repeating Signals From Deep Space Are Extremely Unlikely to Be Aliens. Here’s Why

    “It was so bright that our pipeline initially flagged it as radio frequency interference, signals often caused by cell phones or airplanes that are much closer to home,” says astrophysicist Wen-Fai Fong of Northwestern University in the US.

    “It took some sleuthing by members of our collaboration to uncover that it was a real astrophysical signal.”

    An illustration of the CHIME array detecting RBFLOAT. (Daniëlle Futselaar/MMT Observatory)

    FRBs are among the more delightful and intriguing mysteries of the Universe. As the name suggests, they are very short-lived, but extremely powerful, pulses of radio waves that blast, seemingly at random, from the depths of space.

    Although there can be quite a bit of variation in how they present, FRBs are broadly sorted into two main categories: those that repeat, sometimes on a patterned schedule, and those that flare once and subside, yet to be detected a second time from the same location.

    Repeating FRBs can be predicted, triangulated, and studied with relative ease. One-off FRBs are unpredictable and, because they’re shorter than an eyeblink, a lot more difficult to trace back to a source galaxy.

    To make tracing one-off FRBs less difficult, CHIME has been augmented with smaller, secondary ‘Outrigger’ telescopes, located at great distances from the core facility in Canada. The addition of more detectors gave the researchers the tools they needed to triangulate the signal, down to a resolution of just 45 light-years.

    With the full array of Outriggers online, a team of researchers was able to trace the RBFLOAT (also known as the Root Beer FLOAT, because astronomers like to amuse themselves that way) to the outskirts of a galaxy in the Big Dipper constellation, located at a distance of just 130 million light-years – the closest non-repeating FRB identified to date.

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    This precision localization meant the scientists could then study the environment from which the FRB emerged in incredible detail, using the MMT telescope and the Keck Observatory to conduct follow-up observations.

    This, in turn, helps astronomers narrow down the likely object responsible for the FRB. A growing body of evidence – including an FRB from right here in the Milky Way – suggests that extremely magnetic neutron stars called magnetars are the culprit behind a lot of the FRBs we detect here on Earth.

    “The FRB lies on a spiral arm of its host galaxy,” says astronomer Yuxin “Vic” Dong of Northwestern University.

    “Spiral arms are typically sites of ongoing star formation, which supports the idea that it came from a magnetar. Using our extremely sensitive MMT image, we were able to zoom in further and found that the FRB is actually outside the nearest star-forming clump. This location is intriguing because we would expect it to be located within the clump, where star formation is happening. This could suggest that the progenitor magnetar was kicked from its birth site or that it was born right at the FRB site and away from the clump’s center.”

    The precise location of RBFLOAT on the spiral arm of its host galaxy. (Yuxin “Vic” Dong/MMT Observatory)

    A survey of the location using JWST, published as a second paper, supports this interpretation.

    RBFLOAT, on its own, is an exciting find. Its extreme brightness, and its proximity to Earth, could yield some significant clues about FRBs. Currently, astronomers are trying to figure out if there are any significant differences between repeating and one-off FRBs; and whether magnetars are the only objects that produce them. Data on individual FRBs is important for interrogating these questions.

    But RBFLOAT is one drop in the cosmic ocean – and its detection demonstrates how CHIME just blew open our ability to find other such drops.

    “Thanks to the CHIME Outriggers, we’re now entering a new era of FRB science,” says astronomer Tarraneh Eftekhari of Northwestern University.

    “With hundreds of precisely localized events expected in the next few years, we can start to understand the full breadth of environments from which these mysterious signals emanate, bringing us one step closer to unlocking their secrets. RBFLOAT is just the beginning.”

    The research has been published in The Astrophysical Journal Letters.

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  • Genomic analysis of differentiation and demography of the formerly conspecific agile (Dipodomys agilis) and Dulzura (D. simulans) kangaroo rats

    Genomic analysis of differentiation and demography of the formerly conspecific agile (Dipodomys agilis) and Dulzura (D. simulans) kangaroo rats

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