Mystery Glow of Dark Matter Halos Fueled by Extragalactic Stars
Stars ripped from their home galaxies as they collide with other galaxies can get slung into giant invisible cocoons of dark matter, researchers say, which might explain mysterious radiation pervading the sky. These findings suggest the halos of dark matter surrounding galaxies are not completely dark after all, but contain a small number of stars, investigators added.
In recent decades, satellite telescopes have detected more infrared light emanating from the sky than known galaxies could account for. Scientists had suggested this strange glow might come from sources too dim for observatories to see directly — for instance, the earliest, most distant galaxies. If such primordial galaxies were responsible for this radiation, that might suggest far more of them existed than before thought, potentially radically altering notions of how the cosmos evolved.