A new study published in Astronomy & Astrophysics unveils a powerful way to determine the size of dark matter haloes—the massive, invisible structures that host galaxies—by simply measuring how large galaxies appear in deep astronomical images. Researchers Ignacio Trujillo and Claudio Dalla Vecchia, from the Instituto de Astrofísica de Canarias (IAC) and the Universidad de La Laguna (ULL), demonstrate that galaxy size can serve as a precise proxy for halo size, offering measurements up to six times more accurate than previous methods. Using the cutting-edge EAGLE cosmological simulations

The international BEARD project, led from the Instituto de Astrofísica de Canarias (IAC) and the University of La Laguna (ULL), has used data from several telescopes at the Roque de los Muchachos Observatory, and computer simulations to explain how galaxies similar to the Milky Way have managed to survive the most violent stages of the history of the Universe. The present model for the evolution of the universe predicts an epoch dominated by important mergers of galaxies some ten thousand million years ago. “It’s a case of violent interactions, in which it is foreseeable that weak structures

Our home galaxy, the Milky Way, grew to its current size in part by consuming smaller galaxies. Now, new data from the NASA/ESA Hubble Space Telescope show definitive evidence of a dwarf galaxy merging with the young Milky Way galaxy in the earliest phases of its evolution. This finding extends our knowledge of our galaxy’s history 1.8 billion years farther back in time than before. The results were published today in the journal Nature Astronomy . The Milky Way today is a massive spiral galaxy home to hundreds of billions of stars. However, our galaxy wasn’t always so large; it has grown by