The first rung of the #extragalactic “cosmological distance ladder” is based on calculating the distance to the Cepheids – “breathing” stars, whose changing size sets both how fast they pulse and how bright they are, locking their period and luminosity together.

#GalaxyDynamics

A Deterministic Explanation of Galaxy Rotation Without Dark Matter in the MMA-DMF Framework

[ doi.org/10.5281/zenodo.18857541 ]

#Astrophysics #Cosmology #GalaxyDynamics
#BTFR #DarkMatter #GalaxyRotation #ModifiedGravity
#TheoreticalPhysics

The Petrosian radius is a practical, observation-based definition of galaxy size, defined as the radius where the local surface brightness equals 20% of the mean surface brightness inside that radius.

#GalaxyDynamics

Cette structure de matière noire expliquerait enfin l’étrange danse des galaxies autour de la Voie lactée La saga de la matière noire en astrophysique et cosmologie se décline sous plusieurs aspects. L'un d'eux concerne une énigme du groupe de galaxies contenant la Voie lactée et Andromède, n...

Une structure de matière noire pourrait enfin expliquer l’étrange danse des galaxies autour de la Voie lactée 🌌
www.futura-sciences.com/sciences/act...
#Space #Science #Innovation #Astrophysics #DarkMatter #GalaxyDynamics #MilkyWay #AstroTrends
#LaurentSacco❤️

Disc galaxies have a more complex distribution of stellar populations than ellipticals, featuring ongoing star formation as well as a substantial presence of old stars.

#GalaxyDynamics
#IgnacioFerreras

FRA: Dark Matter as δ-Interference, Dark Energy as Fractal Growth We release a compact FRA pipeline for dark matter (DM) and dark energy (DE).  DM is modeled as ρ_DM(x;L) = κ(L) · σ_δ(x;L)^2, where σ_δ is the coarse-grained  mean of local “difference” strength |δ| o...

FRA-1D turns galaxy rotation data into “dark-matter-free” curves: σ-gradients of gas+stars map straight to ρ_DM, κ ≈ 10⁻¹⁰ across SPARC. Code & full paper here → zenodo.org/records/1774...

#DarkMatter #DarkEnergy #MOND #AstroPhysics #GalaxyDynamics #RotationCurves #OpenScience #Python #SPARC

A Galaxy in Peril: Small Magellanic Cloud Is Being Pulled Apart Nagoya University researchers reveal that the Small Magellanic Cloud is being torn apart by its massive neighbor, offering new insight into how galaxies evolve and interact.

The Small Magellanic Cloud is being pulled apart by its larger neighbor, the Large Magellanic Cloud, according to new research from Nagoya University. #Astronomy #GalaxyDynamics #NagoyaResearch