https://www.theregister.co.uk/2019/10/04/watch_out_andromeda_the_giant_spiral_galaxy_colliding_with_our_own_milky_way_has_devoured_several_galaxies_before/ > Andromeda, a massive spiral galaxy, has swallowed several galaxies within the last few billion years before setting its sights on the Milky Way. > "The Milky Way is on a collision course with Andromeda in about four billion years,” said Dougal Mackey, co-author of a new study published in Nature and a research fellow at the Australian National University. “So knowing what kind of a monster our galaxy is up against is useful in finding out the Milky Way's ultimate fate."