Yet another video of the asteroid belt using Gaia DR3 data with the new shading.

#GaiaSky #Gaia #GaiaDR3 #Space #Asteroids #AsteroidBelt #Astronomy

Weekly Update from the Open Journal of Astrophysics – 24/01/2026

It’s Saturday once more so time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further three papers, bringing the number in Volume 9 (2026) to 14 and the total so far published by OJAp up to 462. This week was slightly affected by a Federal holiday in the USA on January 19th; there were no arXiv announcements the following day.

I will continue to include the posts made on our Mastodon account (on Fediscience) to encourage you to visit it. Mastodon is a really excellent service, and a more than adequate replacement for X/Twitter which nobody should be using.

The first paper to report this week is “The Properties of Little Red Dot Galaxies in the ASTRID Simulation” by Patrick LaChance, Rupert A. C. Croft, Tiziana Di Matteo & Yihao Zhou (Carnegie Mellon U.), Fabio Pacucci (Harvard-Smithsonian CfA), Yueying Ni (U. Michigan Ann Arbor), Nianyi Chen (Princeton U.) and Simeon Bird (UC Riverside), all based in the USA. This paper was published on Monday 19th January 2026 in the folder Cosmology and Nongalactic Astrophysics; the study analyses mock observations of “Little Red Dot” galaxies created from the ASTRID simulation, having high stellar masses and containing massive black holes; not all features match real observations.

The overlay is here:

You can find the officially accepted version on arXiv here and the announcement on Fediverse here:

https://fediscience.org/@OJ_Astro/115921308789068125

The second paper is “Angular bispectrum of matter number counts in cosmic structures” by Thomas Montandon (U. Montpellier, France), Enea Di Dio (U. Genève, Switzerland), Cornelius Rampf (Ruđer Bošković Institute, Croatia) and Julian Adamek (U. Zürich, Switzerland). This was published on Wednesday January 21st, also in the folder Cosmology and Nongalactic Astrophysics. This paper presents thee first full-sky computation of the angular bispectrum in second-order perturbation theory, offering insights into the Universe’s initial conditions, gravity, and cosmological parameters. The results align well with simulations.

The overlay for this one is here:

The official version of the paper can be found on arXiv here and the Fediverse announcement here:

https://fediscience.org/@OJ_Astro/115932387870297108

Next, and last for this week, we have “The Kinematic Properties of TŻO Candidate HV 11417 with Gaia DR3” by Anna J. G. O’Grady (Carnegie Mellon University, USA). This was published on Wednesday 21st January 2026 in the folder Solar and Stellar Astrophysics. This work uses updated data to confirm that HV 11417, a potential Thorne-Żytkow Object, is probably part of the Small Magellanic Cloud and qualifies as a runaway star.

The overlay is here:

The official version can be found on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/115932444483985982

That concludes the update for this week. I will do another next Saturday.

#angularBispectrum #arXiv250105422v3 #arXiv251123368v2 #AstridSimulations #AstrophysicsOfGalaxies #bispectrum #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #GaiaDR3 #largeScaleStructureOfTheUniverse #LittleRedDots #OpenAccess #OpenAccessPublishing #OpenJournalOfAstrophysics #SolarAndStellarAstrophysics #TheOpenJournalOfAstrophysics #ThorneŻytkowObjects

Weekly Update from the Open Journal of Astrophysics – 18/10/2025

It’s time once again for the usual Saturday update of the week’s new papers at the Open Journal of Astrophysics. Since the last update we have published four  more papers, which brings the number in Volume 8 (2025) up to 156, and the total so far published by OJAp up to 391.

I’d like to encourage people to follow our feed on the Fediverse via Mastodon (where I announce papers as they are published, including the all-important DOI) so this week I’ll include links to each announcement there.

The first paper to report is “Shot noise in clustering power spectra” by Nicolas Tessore (University College London, UK) and Alex Hall (University of Edinburgh, UK). This was published in the folder Cosmology and NonGalactic Astrophysics on Tuesday October 14th 2025. This presents a discussion of the effects of ‘shot noise’, an additive contribution due to degenerate pairs of points, in angular galaxy clustering power spectra. Here is a screen grab of the overlay:

You can find the officially accepted version of the paper here. The Mastodon announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Shot noise in clustering power spectra" by Nicolas Tessore (University College London, UK) and Alex Hall (University of Edinburgh, UK)

https://doi.org/10.33232/001c.145919

Next one up is “The Giant Arc – Filament or Figment?” by Till Sawala and Meri Teeriaho (University of Helsinki, Finland). This paper discusses the abundance of large arc-like structures formed in the standard cosmological model, with reference to the “Giant Arc” identified in MgII absorption systems. It was published on Wednesday October 15th in the folder Cosmology and NonGalactic Astrophysics. The overlay is here:

The officially accepted version of this paper can be found on the arXiv here and the Mastodon announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "The Giant Arc – Filament or Figment?" by Till Sawala and Meri Teeriaho (University of Helsinki, Finland)

https://doi.org/10.33232/001c.145931

The third paper this week,  published on Monday 6th October, is “Detecting wide binaries using machine learning algorithms” by Amoy Ashesh, Harsimran Kaur and Sandeep Aashish (Indian Institute of Technology, Patna, India). This was published on Friday 17th October (yesterday) in the folder Astrophysics of Galaxies. It presents a method for detecting wide binary systems in Gaia data using machine learning algorithms.

The overlay is here:

You can find the officially accepted version of this paper on arXiv here. The announcement on Mastodon is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Detecting wide binaries using machine learning algorithms" by Amoy Ashesh, Harsimran Kaur and Sandeep Aashish (Indian Institute of Technology, Patna, India)

https://doi.org/10.33232/001c.146027

The last one this week is “Learned harmonic mean estimation of the Bayesian evidence with normalizing flows” by Alicja Polanska & Matthew A. Price (University College London, UK), Davide Piras (Université de Genève, CH), Alessio Spurio Mancini (Royal Holloway, London, UK) and Jason D. McEwen (University College London). This one was also published on Friday 17th October, but in the folder Instrumentation and Methods for Astrophysics; it presents a new method for estimating Bayesian evidence for use in model comparison, illustrated with a cosmological example.

The corresponding overlay is here:

You can find the officially accepted version on arXiv here. The Mastodon announcement is here:

Open Journal of Astrophysics

@[email protected]

New Publication at the Open Journal of Astrophysics: "Learned harmonic mean estimation of the Bayesian evidence with normalizing flows" by Alicja Polanska & Matthew A. Price (University College London, UK), Davide Piras (Université de Genève, CH), Alessio Spurio Mancini (Royal Holloway, London, UK) and Jason D. McEwen (University College London)

https://doi.org/10.33232/001c.146026

That concludes the papers for this week. With two weeks to go I think we might reach the 400 total by the end of October.

#arXiv240505969v3 #arXiv250511072v2 #arXiv250619942v3 #arXiv250703749v2 #BayesInference #BayesianModelComparison #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAccessPublishing #GAIA #GaiaDR3 #galaxyClustering #GiantArc #InstrumentationAndMethodsForAstrophysics #largeScaleStructureOfTheUniverse #Mastodon #MgIIAbsorptionSystems #normalizingFlows #OpenJournalOfAstrophysics #ShotNoise #WideBinaries

Weekly Update from the Open Journal of Astrophysics – 23/08/2025

So it’s Saturday again, so it’s time for the usual update of papers published at the Open Journal of Astrophysics which I do every Saturday. Since the last update we have published six new papers, which brings the number in Volume 8 (2025) up to 122, and the total so far published by OJAp up to 357. As I mentioned here we have overtaken the total of 120 published in Volume 7 (2024) and are on track for in excess of 180 publications in 2025.

The first paper to report this week is “Mass-feeding of jet-launching white dwarfs in grazing and common envelope evolution” by Noam Soker (Technion, Haifa, Israel). This was published on Tuesday 19th August in the folder Solar and Stellar Astrophysics. It proposes a theoretical suggestion about the production of jets in common-envelope evolution with massive stars.

The overlay is here:

You can make this larger by clicking on it, as you can with all the overlays below. The officially accepted version of this paper can be found on the arXiv here.

The second paper this week, published on Wednesday 20th August in the folder Earth and Planetary Astrophysics, is “Transition metal abundance as a key parameter for the search of Life in the Universe” by Giovanni Covone and Donato Giovannelli (University of Naples, Italy). This paper presents an argument that the availability of transition elements is an essential feature of habitability, and should be considered as such in selecting exoplanetary targets in the search for life.

The overlay is here:

You can find the officially accepted version of the paper on arXiv here.

The third paper this week, also published on 20th August 2025 in the folder Earth and Planetary Astrophysics, is “Discrete element simulations of self-gravitating rubble pile collisions: the effects of non-uniform particle size and rotation” by Job Guidos, Lucas Kolanz and Davide Lazzati (Oregon State University, USA).  This presents a new computer code for simulating the growth of granular masses through collisions of smaller particles and discusses results generated by it.

The overlay for this one is here:

You can find the officially accepted version on arXiv here.

The next paper, the fourth this week, is “Seeing the Outer Edge of the Infant Type Ia Supernova 2024epr in the Optical and Near Infrared” by W.B. Hoogendam (University of Hawaii, USA) and 32 others – too numerous to list by name – based in various institutes in the USA, Australia, UK, Denmark, Taiwan and China. This paper was also published on Wednesday 20th August 2025, but in the folder High-Energy Astrophysical Phenomena.  The article reports on the results of optical-to-near-infrared photometry and spectroscopy of the Type Ia supernova (SN Ia) 2024epr and a discusses how these challenge models for this sort of supernova.

The overlay is here:

You can find the officially accepted version on arXiv here.

The fifth paper this week is “Computing Nonlinear Power Spectra Across Dynamical Dark Energy Model Space with Neural ODEs” by Peter L. Taylor of Ohio State University (USA).  This one shows how to compute the evolution of cosmological power spectra into the non-linear regime via neural differential equations. It was published on Friday 22nd August 2025 in the folder Cosmology and NonGalactic Astrophysics. The overlay is here:

You can find the officially accepted version on arXiv here.

And finally for this week we have “Symbiotic star candidates in Gaia Data Release 3” by Samantha E. Ball & Benjamin C Bromley (University of Utah, USA) and Scott J. Kenyon (Smithsonian Observatory, USA). This paper was published on Friday 22nd August in the folder Solar and Stellar Astrophysics. It describes a new search for symbiotic star candidates in Gaia Data Release 3 (GDR3), based on astrometric, photometric, and spectroscopic information. The overlay is here:

You can find the officially accepted version of this one on arXiv here.

And that’s all the papers for this week. I suppose there will come a time when we publish a paper on every day of the week and each week’s summary will contain a paper in each of the astro-ph categories on arXiv, but we haven’t done that yet. This week we published on every day but Monday 18th August, and have papers in four of the six categories.

#arXiv220703748v5 #arXiv241022189v2 #arXiv250217556v2 #arXiv250522621v2 #arXiv250609128v2 #arXiv250620505v2 #asteroids #commonEnvelopeEvolution #Cosmology #CosmologyAndNonGalacticAstrophysics #DiamondOpenAccess #DiamondOpenAcessPublishing #EarthAndPlanetaryAstrophysics #GaiaDR3 #Habitability #HighEnergyAstrophysicalPhenomena #NeuralDifferentialEquations #OpenJournalOfAstrophysics #planetesimals #powerSpectra #rubblePiles #SolarAndStellarAstrophysics #SymbioticStars #TheOpenJournalOfAstrophysics #TransitionMetals #whiteDwarfs

📢📢 Today we make available a new Gaia DR3-based catalog: Gaia DR3 Best!

It is a small and compact catalog with only the very best stars in terms of parallax relative error. It contains 646K stars and weighs ~54 MB.

All the info: http://gaiasky.space/news/2025/new-catalog-dr3-best/

#GaiaSky #Catalog #GaiaDR3

GAIA vindt meer dan 350 asteroïden met verborgen manen

De GAIA-missie heeft potentiële manen gevonden die rond 350 asteroïden draaien waarvan eerder werd voorspeld dat het eenlingen waren. GAIA had al bekende asteroïde-dubbelsystemen onderzocht en bevestigd dat ze metgezellen hebben

https://www.kuuke.nl/gaia-vindt-meer-dan-350-asteroiden-met-verborgen-manen/

#asteroden #BinaireAsteroden #didymos #Dimorphos #gaia #GaiaDR3

Nieuwe getijdenstroom gevonden met Gaia

Door de gegevens van de Europese Gaia-satelliet te bestuderen hebben Chinese astronomen op het noordelijk halfrond een nieuwe getijdenstroom van sterren gvonden. De getijdenstroom heeft een lage metalliciteit en een relatief hoge energie.

https://www.kuuke.nl/nieuwe-getijdenstroom-gevonden-met-gaia/

#gaia #GaiaDR3 #getijdesntroom #halo #melkweg #RRLyraesterren