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Fine-tunings in radiative $alpha$-particle capture on $^{12}$C at astrophysical energies Ulf-G. Mei{ss}ner, Bernard Ch. Metsch, Helen Meyer arXiv:2601.11180v2 Announce Type: replace-cross Abstract: We investigate the fine-tuning of radiative alpha-particle capture on carbon, $alpha(^{12}{rm C},^{16}{rm O})gamma$, at astrophysical energies. Utilizing results from cluster effective field theory for this reaction, we find that the low-energy data of the astrophysical S-factor allow for only very small variations in the electromagnetic fine-structure constant $alpha$, namely $|delta alpha/alpha| leq 0.2,$ per mille, in both the $E1$ and the $E2$ radiative capture.arXiv:2601.11180v2 Announce Type: replace-cross Abstract: We investigate the fine-tuning of radiative alpha-particle capture on carbon, $alpha(^{12}{rm C},^{16}{rm O})gamma$, at astrophysicalRead More →

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Axion dark matter from extended misalignment with a constant-$omega_phi$ pre-oscillatory phase and dark radiation Jos’e Mar’ia P’erez-Poyatos arXiv:2604.27954v2 Announce Type: replace Abstract: In this work, we extend the standard pre-inflationary misalignment mechanism for axion-like particles (ALPs) by introducing a pre-oscillatory phase with constant equation of state $omega_phiin[-1,1]$, generated by a tracking potential. During the radiation-dominated era, the potential undergoes a rapid transition to the conventional cosine potential. The resulting change in the potential energy across the transition can drive the ALP into a kinetic misalignment phase ($omega_phi=1$) prior to the onset of oscillations. Motivated by persistent cosmological tensions, such as those in $H_0$ and $S_8$,Read More →

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“Simplified Proteins” Reveal the Biochemical Dawn of Early Earth When researchers look up at the sky and wonder if we’re not alone, they also realize the origins of life here on Earth might hold the key to finding out. The chaotic chemical soup of our early world eventually led to the staggering complexity of modern life, but how exactly did it start? Proteins were one of the key ingredients in the early years, but we’re still only just discovering how these marvels of modern biology first managed to fold, function, and survive. A new review paper, The borderlands of foldability: lessons from simplified proteins, publishedRead More →

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The Asteroid Hunter Somewhere out there, hurtling through space in the darkness, is an asteroid with our name on it. We just don’t know which one yet. NASA’s answer to that uncomfortable truth is NEO Surveyor, a purpose built infrared space telescope currently taking shape in laboratories across America, and scheduled for launch in 2027. The stakes, quite literally, could not be higher. Universe Today Go to SourceRead More →

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Ultrahigh-energy cosmic messengers may carry ultraheavy secrets There may be an ultraheavy explanation for the mystery surrounding the origins of the highest-energy particles ever observed. Ultrahigh-energy cosmic rays are particles from space that strike Earth with energies far beyond those reachable by human-made particle accelerators. One of the most extreme events ever recorded is the “Amaterasu particle,” detected by the Telescope Array in Utah in 2021 and named after the sun goddess in Japanese mythology. Its reported energy places it among the highest-energy cosmic-ray events ever observed, comparable to the “Oh-My-God particle” detected in 1991, yet its origin—and even its identity—remain uncertain. phys.org Go toRead More →

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How Massive Star Clusters Shape Galaxy Evolution A team of researchers used the NASA/ESA/CSA James Webb Space Telescope together with the NASA/ESA Hubble Space Telescope to observe almost 9,000 star clusters in four nearby galaxies. They studied younger clusters that were still embedded in their natal gas clouds, and older ones that had dissipated that gas. Their results show that more massive star clusters emerge more quickly from their birth, clearing away gas and filling the galaxy with ultraviolet light. The research presents a better understanding of star formation in galaxies, something lacking in scientific simulations, as well as how and where planets can form.Read More →

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Ringing the GONG: New Details About the Sun’s Far-side Activities For years, when something happened on the far side of the Sun, we didn’t know much, if anything about it. Sunspots could form there, flares could lash out and the corona could send masses of material out to space. However, we didn’t know about any of this until those active regions rotated around to our view. In the late 1900s, scientists came up with a technique called helioseismology to analyze sound waves created by such activity as they echoed through the Sun. Universe Today Go to SourceRead More →

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These monster black holes did not form the usual way—their history of violence is written into spacetime ripples The most massive black holes in the universe detected by the ripples they make in spacetime were not born directly from collapsing stars, according to a new study. These cosmic giants instead build up through a series of repeated and extremely violent collision events in very densely populated star clusters, an international team of researchers argue. phys.org Go to SourceRead More →

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Extreme Galaxy-scale Outflows Are Frequent among Luminous Early Quasars Weizhe Liu, Xiaohui Fan, Huan Li, Richard Green, Jinyi Yang, Xiangyu Jin, Jianwei Lyu, Maria Pudoka, Yongda Zhu, Eduardo Banados, Silvia Belladitta, Thomas Connor, Tiago Costa, Roberto Decarli, Anna-Christina Eilers, Hyunsung Jun, Madeline A. Marshall, Chiara Mazzucchelli, Jan-Torge Schindler, Yue Shen, Sylvain Veilleux, Julien Wolf, Huanian Zhang, Mingyang Zhuang, Siwei Zou, Mingyu Li arXiv:2509.08793v2 Announce Type: replace Abstract: The existence of abundant post-starburst/quiescent galaxies just $sim$1-2 Gyrs after the Big Bang challenges our current paradigm of galaxy evolution. Cosmological simulations suggest that quasar feedback is likely the most promising mechanism responsible for such rapid quenching. HereRead More →

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Data-Constrained Modeling of Electron Transport and Asymmetric Precipitation in the 2011 August 4 Solar Flare Feiyu Yu, Xiangliang Kong, Ze Zhong, Zhentong Li, Zelong Jiang, Yingli Cui, Zhao Wu, Yao Chen, Gang Li arXiv:2605.03380v2 Announce Type: replace Abstract: Energetic electrons accelerated at coronal reconnection sites during solar flares precipitate into the lower solar atmosphere, generating nonthermal emissions and regulating energy deposition. However, how their transport and precipitation are jointly governed by the three-dimensional (3D) magnetic topology, turbulent scattering, and Coulomb collisions remains unclear. Here, we aim to disentangle these physical processes by using a data-constrained 3D particle transport model for the 2011 August 4 flare.Read More →

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The emerging timescale of young star clusters regulated by cluster stellar mass Alex Pedrini, Angela Adamo, Daniela Calzetti, Arjan Bik, Thomas J. Haworth, Bruce G. Elmegreen, Mark R. Krumholz, Sean T. Linden, Benjamin Gregg, Helena Faustino Vieira, Varun Bajaj, Jenna E. Ryon, Ahmad A. Ali, Eric P. Andersson, Giacomo Bortolini, Michele Cignoni, Ana Duarte-Cabral, Kathryn Grasha, Natalia Lah’en, Thomas S. -Y. Lai, Drew Lapeer, Matteo Messa, G"oran "Ostlin, Elena Sabbi, Linda J. Smith, Monica Tosi arXiv:2603.09867v2 Announce Type: replace Abstract: Quantifying the timescales of star cluster emergence from their natal clouds remains one of the main challenges in understanding the star formation process. These timescalesRead More →

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The relativistic restricted three-body problem: geometry and motion around tidally perturbed black holes Takuya Katagiri, Vitor Cardoso arXiv:2601.14979v2 Announce Type: replace-cross Abstract: We investigate the geometry of a tidally deformed, rotating black hole and timelike geodesics in its vicinity. Our framework provides a local picture of the structural evolution of a relativistic restricted three-body problem around a deformed black hole in an adiabatically evolving binary, motivated by various astrophysical settings including disk dynamics and extreme mass-ratio inspirals. As the tidal-field strength is increased, initially regular, bound geodesics undergo four stages: (i) weak chaos emerges within the bound motion; (ii) a subset of trajectories plunges intoRead More →

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Roman Space Telescope poised to transform hunt for elusive neutron stars Astronomers have long known that neutron stars, the crushed cores left behind after massive stars explode, should be scattered throughout the Milky Way galaxy. However, most of them are effectively invisible. A new study published in Astronomy & Astrophysics suggests that NASA’s upcoming Nancy Grace Roman Space Telescope could spot them anyway. phys.org Go to SourceRead More →

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Astronomers Witness the Awesome Power of a Black Hole’s “Dancing Jets” New Curtin University-led research has used a radio telescope that spans the Earth to snap images that measure the immense power of jets from black holes, confirming scientists’ theories of how black holes help shape the structure of the Universe. Universe Today Go to SourceRead More →

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How quasars shut down star formation in the early universe Supermassive black holes lurk at the centers of massive galaxies, including our own Milky Way. Puzzlingly, supermassive black holes more than a billion times the mass of the sun appear to exist just a few hundred million years after the Big Bang, when the universe was less than 5% of its current age. As interstellar gas spirals towards such black holes, it accelerates to extreme speeds, heats up, and emits intense radiation across the electromagnetic spectrum, creating a “quasar.” phys.org Go to SourceRead More →

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A new way to read the universe could sharpen understanding of cosmic expansion and dark energy An international team led by researchers at the Institute of Cosmos Sciences of the University of Barcelona (ICCUB) has developed a new method that could significantly improve our understanding of the expansion of the universe and the nature of dark energy. phys.org Go to SourceRead More →

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J1152 is an unusual long-period dwarf nova with recurring eclipses, observations find Astronomers from the South African Astronomical Observatory (SAAO) and elsewhere have conducted photometric and spectroscopic observations of a cataclysmic variable system designated SRGA J115215.0−510656. Results of the new observations, published April 29 on the arXiv pre-print server, indicate that the investigated system is an unusual long-period dwarf nova. phys.org Go to SourceRead More →

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Data Fusion Provides a High-Definition Look At Mars’ Temperature Maps In-situ Resource Utilization (ISRU) is our best bet for “living off the land” for a future Martian base, but tracking down those resources is no easy task. As of now, we have two options – send a rover to a specific location to scout it, or monitor it from orbit. Since rovers are expensive, and there are an absolute ton of sites that we would eventually want to scout, doing so from orbit would seem a better option. But monitoring for temperature, one of the most important orbital scans we can do, is notoriously blurryRead More →