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Artemis Astronauts Will Deploy New Seismometers on the Moon Back in the 1960s and 1970s, Apollo astronauts set up a collection of lunar seismometers to detect possible Moon quakes. These instruments monitored lunar activity for eight years and gave planetary scientists an indirect glimpse into the Moon’s interior. Now, researchers are developing new methods for lunar quake detection techniques and technologies. If all goes well, the Artemis astronauts will deploy them when they return to the Moon. Fiber optic cable is the heart of a seismology network to be deployed on the Moon by future Artemis astronauts. The new approach, called distributed acoustic sensing (DAS),Read More →

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Ice Deposits on Ceres Might Only Be a Few Thousand Years Old The dwarf planet Ceres has some permanently dark craters that hold ice. Astronomers thought the ice was ancient when they were discovered, like in the moon’s permanently shadowed regions. But something was puzzling. Why did some of these shadowed craters hold ice while others did not? Ceres was first discovered in 1801 and was considered a planet. Later, it was thought to be the first asteroid ever discovered, since it’s in the main asteroid belt. Since then, our expanding knowledge has changed its definition: we now know it as a dwarf planet. EvenRead More →

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The Mystery of Cosmic Rays Deepens Cosmic rays are high-energy particles accelerated to extreme velocities approaching the speed of light. It takes an extremely powerful event to send these bits of matter blazing through the Universe. Astronomers theorize that cosmic rays are ejected by supernova explosions that mark the death of supergiant stars. But recent data collected by the Fermi Gamma-ray space telescope casts doubt on this production method for cosmic rays, and has astronomers digging for an explanation. It’s not easy to tell where a cosmic ray comes from. Most cosmic rays are hydrogen nuclei, others are protons, or free-flying electrons. These are chargedRead More →

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NASA Confirms that a Piece of its Battery Pack Smashed into a Florida Home NASA is in the business of launching things into orbit. But what goes up must come down, and if whatever is coming down doesn’t burn up in the atmosphere, it will strike Earth somewhere. Even Florida isn’t safe. Careful consideration goes into releasing debris from the International Space Station. Its mass is measured and calculated so that it burns up during re-entry to Earth’s atmosphere. But in March 2024, something didn’t go as planned. It all started in 2021 when astronauts replaced the ISS’s nickel hydride batteries with lithium-ion batteries. ItRead More →

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Constraining on the non-standard cosmological models combining the observations of high-redshift quasars and BAO Ziqiang Liu, Tonghua Liu, Xinyi Zhong, Yifei Xu, Xiaogang Zheng arXiv:2404.10794v1 Announce Type: new Abstract: In this work, we studied four types of cosmological models with different mechanisms driving the accelerated expansion of the universe, include Braneworld models, Chaplygin Gas models, Emergent Dark Energy models, and cosmological torsion models. Considering that the dynamics of these models at low redshifts are very similar and difficult to distinguish, we used the latest and largest UV and X-ray measurements of quasars (QSOs) observations covering the range of redshift $0.009arXiv:2404.10794v1 Announce Type: new Abstract: InRead More →

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The Co-Evolution Between Galaxies and Dark Matter Halos Aldo Rodriguez-Puebla arXiv:2404.10801v1 Announce Type: new Abstract: The current cosmological paradigm asserts that dark matter halos provide the gravitational scaffolding for galaxy formation through a combination of hierarchical structure formation and non-linear local (g)astrophysical processes. This close relationship, known as the galaxy-halo connection, suggests that the growth and assembly of dark matter halos impact the properties of galaxies. While the stellar mass of galaxies correlates strongly with the mass of their halos, it is important to note that the galaxy-halo connection encompasses a broader distribution of galaxy and halo properties. This distribution can be constrained using dataRead More →

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Vorticity and magnetic dynamo from subsonic expansion waves II: Dependence on magnetic Prandtl number, forcing scale, cooling time Albert Elias-L’opez, Fabio del Sordo, Daniele Vigan`o arXiv:2404.10804v1 Announce Type: new Abstract: The amplification of astrophysical magnetic fields takes place via dynamo instability in turbulent environments. The presence of vorticity is crucial for the dynamo to happen. However, the role of vorticity is not yet fully understood. This work is an extension of previous research on the effect of an irrotational subsonic forcing on a magnetized medium in the presence of rotation or a differential velocity profile, aimed at exploring a wider parameter space in terms ofRead More →

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New AGN diagnostic diagrams based on the [OIII]$lambda 4363$ auroral line G. Mazzolari, H. "Ubler, R. Maiolino, X. Ji, K. Nakajima, A. Feltre, J. Scholtz, F. D’Eugenio, M. Curti, M. Mignoli, A. Marconi arXiv:2404.10811v1 Announce Type: new Abstract: The James Webb Space Telescope (JWST) is revolutionizing our understanding of black holes formation and growth in the early Universe. However, JWST has also revealed that some of the classical diagnostics, such as the BPT diagrams and X-ray emission, often fail to identify narrow line TypeII active galactic nuclei (AGN) at high redshift. Here we present three new rest-frame optical diagnostic diagrams leveraging the [OIII]$lambda4363$ auroral line,Read More →

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JWST Photometry of Globular Clusters in Abell 2744. II: luminosity and color distributions William E. Harris, Marta Reina-Campos arXiv:2404.10813v1 Announce Type: new Abstract: Deep JWST imaging of the giant galaxy cluster Abell 2744, at redshift $z=0.308$, is used to explore the features of its rich population of globular clusters (GCs), building on our initial survey of the system (Harris & Reina-Campos 2023). We use the photometry of more than $10,000$ GCs over a three-magnitude range to construct the GC luminosity function (GCLF) and color distribution (CDF). These results now specifically account for photometric incompleteness as a function of location relative to the five giant galaxiesRead More →

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FRESCO: The Paschen-$alpha$ Star Forming Sequence at Cosmic Noon Chloe Neufeld, Pieter van Dokkum, Yasmeen Asali, Alba Covelo-Paz, Joel Leja, Jamie Lin, Jorryt Matthee, Pascal A. Oesch, Naveen A. Reddy, Irene Shivaei, Katherine E. Whitaker, Stijn Wuyts, Gabriel Brammer, Danilo Marchesini, Michael V. Maseda, Rohan P. Naidu, Erica J. Nelson, Anna Velichko, Andrea Weibel, Mengyuan Xiao arXiv:2404.10816v1 Announce Type: new Abstract: We present results from the JWST First Reionization Epoch Spectroscopically Complete Observations survey (FRESCO) on the star forming sequence of galaxies at $1.09.5 M_odot$ that are lower than found in many earlier studies by up to 0.6 dex, but in good agreement with recentRead More →

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Spectroscopic characterisation of gravitationally lensed stars at high redshifts Emma Lundqvist, Erik Zackrisson, Calum Hawcroft, Anish M. Amarsi, Brian Welch arXiv:2404.10817v1 Announce Type: new Abstract: Deep imaging of galaxy cluster fields have in recent years revealed tens of candidates for gravitationally lensed stars at redshifts $zapprox$ 1-6, and future searches are expected to reveal highly magnified stars from even earlier epochs. Multi-band photometric observations may be used to constrain the redshift, effective temperature $T_mathrm{eff}$ and dust attenuation along the line of sight to such objects. When combined with an estimate of the likely magnification, these quantities may be converted into a constraint on the stellarRead More →

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The first degree-scale starlight-polarization-based tomography map of the magnetized interstellar medium V. Pelgrims, N. Mandarakas, R. Skalidis, K. Tassis, G. V. Panopoulou, V. Pavlidou, D. Blinov, S. Kiehlmann, S. E. Clark, B. S. Hensley, S. Romanopoulos, A. Basyrov, H. K. Eriksen, M. Falalaki, T. Ghosh, E. Gjerl{o}w, J. A. Kypriotakis, S. Maharana, A. Papadaki, T. J. Pearson, S. B. Potter, A. N. Ramaprakash, A. C. S. Readhead, I. K. Wehus arXiv:2404.10821v1 Announce Type: new Abstract: We present the first degree-scale tomography map of the dusty magnetized interstellar medium (ISM) from stellar polarimetry and distance measurements. We used the RoboPol polarimeter at Skinakas Observatory to conductRead More →

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In: arXiv

The CAVITY project. The spatially resolved stellar population properties of galaxies in voids Ana M. Conrado, Rosa M. Gonz’alez Delgado, Rub’en Garc’ia-Benito, Isabel P’erez, Simon Verley, Tom’as Ruiz-Lara, Laura S’anchez-Menguiano, Salvador Duarte Puertas, Andoni Jim’enez, Jes’us Dom’inguez-G’omez, Daniel Espada, Mar’ia Argudo-Fern’andez, Manuel Alc’azar-Laynez, Guillermo Bl’azquez-Calero, Bahar Bidaran, Almudena Zurita, Reynier Peletier, Gloria Torres-R’ios, Estrella Florido, M’onica Rodr’iguez Mart’inez, Ignacio del Moral-Castro, Rien van de Weygaert, Jes’us Falc’on-Barroso, Alejandra Z. Lugo-Aranda, Sebasti’an F. S’anchez, Thijs van der Hulst, H’el`ene M. Courtois, Anna Ferr’e-Mateu, Patricia S’anchez-Bl’azquez, Javier Rom’an, Jes’us Aceituno arXiv:2404.10823v1 Announce Type: new Abstract: The Universe is shaped as a web-like structure, formed by clusters, filaments,Read More →

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Probing the optical depth with galaxy number counts Selim C. Hotinli, Gilbert P. Holder arXiv:2404.10825v1 Announce Type: new Abstract: We study the prospects for measuring the cosmological distribution and abundance of ionized electrons in the intergalactic medium using galaxy surveys. Optical light from distant galaxies is subject to Thomson screening by intervening electrons which distorts the observed galaxy number density, similar to the effect of weak gravitational lensing magnification. We construct an estimator for the optical-depth fluctuations from the statistical anisotropies of galaxy number counts induced by the spatially-varying optical-depth field. We find near-future galaxy surveys can detect this signal at signal-to-noise above $sim10$ dependingRead More →

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The link between Athor and EL meteorites does not constrain the timing of the giant planet instability Andre Izidoro, Rogerio Deienno, Sean N. Raymond, Matthew S. Clement arXiv:2404.10828v1 Announce Type: new Abstract: The asteroid Athor, residing today in the inner main asteroid belt, has been recently associated as the source of EL enstatite meteorites to Earth. It has been argued that Athor formed in the terrestrial region — as indicated by similarity in isotopic compositions between Earth and EL meteorites — and was implanted in the belt $gtrsim$60 Myr after the formation of the solar system. A recently published study modelling Athor’s implantation in theRead More →