Weighing the Milky Way's Satellite Galaxies Using Pulsar Accelerations: https://arxiv.org/abs/2512.10883 -> UAH researchers find new method to “weigh” neighboring galaxies using #pulsars as ultra-precise gravitational probes: https://www.uah.edu/science/science-news/20271-uah-researchers-find-new-method-to-weigh-neighboring-galaxies-using-pulsars-as-ultra-precise-gravitational-probes
Weighing the Milky Way's Satellite Galaxies Using Pulsar Accelerations

The properties of dwarf galaxies orbiting the Milky Way (MW) are useful for testing models of the formation of our Galaxy, and by extension various theories of cosmology. Recent efforts to measure the masses of the MW's satellite dwarf galaxies have relied on the motions and positions of stars in the MW's disk and halo, which are perturbed by the passage of satellite galaxies. As there are many known processes in our Galaxy that lead to observed disequilibrium in stars, these kinematic methods have been limited by the inherent difficulty in identifying only the perturbations due to particular satellite galaxies. We present a novel method for determining the masses of two MW satellite galaxies -- the Large Magellanic Cloud (LMC) and the Sagittarius Dwarf Spheroidal Galaxy (Sgr dSph) -- using only direct, instantaneous acceleration data derived from extremely precise timing of millisecond pulsars near the Sun. As the LMC and Sgr dSph orbit the MW, they cause wave-like distortions in the structure of the disk plus a large-scale offset in the centers of mass of the dark matter halo and the baryonic disk. These two effects lead to asymmetric accelerations above and below the disk midplane near the Sun, which is observed in the pulsar acceleration data. Notably, the amplitude of this asymmetry is shown to depend on the masses of the orbiting satellites. We analyze a grid of simulations with varying masses of each satellite. We find the total (dark + baryon) mass enclosed within the tidal radius at the present day for the LMC to be 4.1 $\pm$ 1.0 $\times$ 10$^{10}$ M$_\odot$ within a radius of 16.6 kpc, and for Sgr to be 3.5 $\pm$ 2.4 $\times$ 10$^8$ M$_\odot$ within a radius of 5 kpc. These results are generally consistent and competitive with previous determinations of the masses of these objects, but entirely independent of any stellar kinematic data for the first time.

arXiv.org

Weekly Update from the Open Journal of Astrophysics – 23/05/2026

It’s Saturday once again, so time for another update of activity at the Open Journal of Astrophysics. Since the last update we have published a further six papers, bringing the number in Volume 9 (2026) to 110 and the total so far published by OJAp up to 558.

I will continue to include the posts made on our Mastodon account (on Fediscience); these announcements also show the DOI for each paper.

The first paper to report this week, published on Monday 18th May in the folder Instrumentation and Methods for Astrophysics is “Edges In Coadded Images” by Erin Sheldon (Brookhaven National Laboratory, USA). This paper describes a study exploring how image discontinuities and noise impact weak gravitational lensing measurements, finding no significant biases under typical conditions. Biases occur only in extreme cases, but can be mitigated.

The overlay for this paper is here

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

https://fediscience.org/@OJ_Astro/116594222032390191

The second paper for this week, also published on Monday 18th May but in the folder Cosmology and Nongalactic Astrophysics, is “Joint cosmological fits to DESI-DR1 full-shape clustering and weak gravitational lensing in configuration space” by A. Semenaite (Swinburne Institute of Technology, Australia) and 72 other authors from all round the world. This paper presents a cosmological analysis of correlations between the DESI-DR1 Bright Galaxy Survey and Luminous Red Galaxy samples and overlapping shear measurements from various weak lensing surveys.

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/116594256215421009

Next one up, the third paper of the week, and the third published on Monday 18th May, and in the folder Cosmology and Nongalactic Astrophysics is “Probing Dark Energy Microphysics with kSZ Tomography” by Julius Adolff, Selim Hotinli and Neal Dalal (all of the Perimeter Institute, Canada). This paper explores how kinetic Sunyaev-Zel’dovich tomography and galaxy clustering can enhance our understanding of dark energy and its effects, potentially revealing its microphysical properties in future surveys.

The overlay for this one is here:

The final, accepted version can be found on arXiv here and the Mastodon announcement is here:

https://fediscience.org/@OJ_Astro/116594304124291605

The fourth paper this week, published on Wednesday May 20th is “A Census of Variable Radio Sources at 3 GHz” by Yjan A. Gordon, Peter S. Ferguson, Michael N. Martinez and Eric J. Hooper (all of the University of Wisconsin, USA). This article, published in the folder Astrophysics of Galaxies, uses data from the Very Large Array Sky Survey to analyze variability in the radio sky, finding most changes consistent with blazars and quasars.

The overlay is here:

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

https://fediscience.org/@OJ_Astro/116607468481260244

The fifth article of this week was published on Friday 22nd May in the folder Instrumentation and Methods for Astrophysics. The title is “Uncovering the Next Galactic Supernova with the Vera C. Rubin Observatory” by John Banovetz (Lawrence Berkeley Lab., USA), Claire-Alice Hebert & Peter B. Denton (Brookhaven National Lab., USA), Dan Scolnic (Duke University, USA), Anze Slosar (Brookhaven) and Chris Walter (Duke). The paper presents a study simulating how effectively the Vera C. Rubin Observatory can localize supernovae using neutrino triggers, finding a 57-97% success rate based on stellar mass density predictions.

The overlay is here:

You can find the authorized version of this paper on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/116617293753093751

Last, but by no means least, this week we have “Pulsar timing solutions for 17 pulsars at 150 MHz from the Irish LOFAR station” by David J. McKenna (ASTRON, The Netherlands), Evan F. Keane (Trinity College Dublin, Ireland), Peter T. Gallagher (DIAS, Ireland) and Joe McCauley (Trinity). This was published on Friday 22nd May in the folder High-Energy Astrophysical Phenomena. It presents a demonstration of the use of international Low Frequency Array (LOFAR) stations in tracking and characterizing pulsars, providing new insights into these neutron stars’ emission properties.

The overlay for this one is here:

You can find the authorized version of this paper on arXiv here and the Fediverse announcement is here:

https://fediscience.org/@OJ_Astro/116617404344791486

And that concludes this week’s update. I’ll do another one next Saturday.

#arXiv250800976v2 #arXiv250906929v3 #arXiv251105653v2 #arXiv251215961v2 #arXiv260112094v2 #arXiv260522516v1 #AstrophysicsOfGalaxies #blazars #cosmicShear #cosmologicalSimulations #CosmologyAndNonGalacticAstrophysics #DarkEnergy #DarkEnergySpectroscopicInstrument #DarkEnergySurvey #DiamondOpenAccess #DiamondOpenAccessPublishing #galaxyClustering #HighEnergyAstrophysicalPhenomena #InstrumentationAndMethodsForAstrophysics #kineticSunyaevZeDovichEffect #LOFAR #OpenAccess #OpenAccessPublishing #PointSpreadFunction #pulsars #quasars #radioAstronomy #stackedImages #SunyaevZeDovichEffect #supernova #supernovae #Tomography #VeraCRubinObservatory #VeryLargeArray #weakGravitationalLensing
Funkelnder Pulsar verrät unsichtbare Strukturen im Weltraum

Ein internationales Team um Tim Sprenger vom Max-Planck-Institut für Radioastronomie nutzte zwei der weltweit leistungsstärksten Radioteleskope, um das Flackern des Pulsars PSR B150855 zu analysieren. Die Radiostrahlung wird durch geordnete Strukturen im interstellaren Medium gestreut, etwa 430 Lichtjahre entfernt. Die innovative Technik ermöglicht hochaufgelöste Bilder ohne ein globales Teleskopnetzwerk.

Les pulsars cachent un secret: leurs signaux radio viennent aussi de zones lointaines, pas juste des pôles. Notre modèle classique vacille www.techno-science.net/actualite/pu... #Space #Science #Innovation #Astrophysics #NeutronStars #Pulsars #Fermi #NewSpace

⚡ Les pulsars sont bien plus r...
⚡ Les pulsars sont bien plus riches qu'on ne le pensait

Des cœurs d'étoiles mortes en rotation rapide, les pulsars, semblent émettre des signaux radio non seulement depuis...

Techno-Science.net
Les pulsars cachent un secret: leurs signaux radio viennent aussi de zones lointaines, pas juste des pôles. Notre modèle classique vacille
https://www.techno-science.net/actualite/pulsars-sont-bien-plus-riches-qu-on-ne-pensait-N28633.html
#Space #Science #Innovation #Astrophysics #NeutronStars #Pulsars #Fermi #NewSpace
⚡ Les pulsars sont bien plus riches qu'on ne le pensait

Des cœurs d'étoiles mortes en rotation rapide, les pulsars, semblent émettre des signaux radio non seulement depuis...

Techno-Science.net
New in the #VirtualObservatory: “HTRU-North pulsar survey. III” by Houben L.J.M. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/708/A199
#RadioSources #Pulsars
VizieR J/A+A/708/A199

VizieR catalogues

New in the #VirtualObservatory: “Flare param. from K2 & TESS data of PSR J1023+0038” by Zhang L.-Y. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/960/20
#VisibleAstronomy #Photometry #StellarFlares #Pulsars
VizieR J/ApJ/960/20

VizieR catalogues

Radiosignale aus dem Randbereich extremer Sterne

Ein Team von Astronomen hat festgestellt, dass einige der am schnellsten rotierenden Sterne, die sogenannten Millisekundenpulsare, Radiowellen aus verschiedenen, weit voneinander entfernten Regionen aussenden. Diese Erkenntnis stellt die bisherige Annahme in Frage, dass Radiowellen nur in der Nähe der Sternoberfläche erzeugt werden. Die Entdeckung zeigt, dass die Signale aus Bereichen stammen können, in denen Magnetfelder mit nahezu Lichtgeschwindigkeit rotieren.

NASA’s Hubble Revisits Crab Nebula to Track 25 Years of Expansion

Hubble takes a fresh look at the Crab Nebula revealing, in unparalleled detailed, the aftermath of a supernova and how it evolved over 25 years.

NASA Science