Some remarkable examples of alternative cosmological theories are reviewed here, ranging from a compilation of variations on the Standard Model through the more...
An almost dark galaxy with the mass of the Small Magellanic Cloud
Almost dark galaxies are objects that have eluded detection by traditional surveys such as the Sloan Digital Sky Survey (SDSS). The low surface brightness of...
Anisotropic satellite accretion on to the Local Group with HESTIA
How the cosmic web feeds haloes, and fuels galaxy formation is an open question with wide implications. This study explores the mass assembly in the Local Group...
Anisotropy measurements of the cosmic microwave background radiation at intermediate angular scales
Galaxy formation by gravitational instability implies the presence of temperature fluctuations in the cosmic microwave background. New observations at 10.45 and...
Appearances can be deceiving: clear signs of accretion in the seemingly ordinary Sextans dSph
We report the discovery of clear observational signs of past accretion/merger events in one of the Milky Way satellite galaxies, the Sextans dwarf spheroidal...
Application of the Eddington inversion method to constrain the dark matter halo of galaxies using only observed surface brightness profiles
Context. The halos of low-mass galaxies may allow us to constrain the nature of dark matter (DM), but the kinematic measurements needed to diagnose the required...
Dark matter makes up most of the mass of the Universe but remains mysterious. I discuss recent progress in constraining its properties by measuring its...
Bar pattern speed at z∼1-2 to explore challenges of the Standard Cosmology
Stellar bars drive the galaxy secular evolution. While rotating around the galaxy centre with a given angular frequency, the bar pattern speed, they sweep...
Baryon effects on the internal structure of ΛCDM haloes in the EAGLE simulations
We investigate the internal structure and density profiles of haloes of mass 1010-1014 M⊙ in the Evolution and Assembly of Galaxies and their Environment (EAGLE...