Hubble and Gaia Solve Milky Way's Early Merger Mystery

New data from the NASA/ESA Hubble Space Telescope, combined with Gaia data, has provided definitive evidence of a dwarf galaxy merging with the young Milky Way approximately 11.8 billion years ago. This discovery extends our understanding of the galaxy's evolution 1.8 billion years further back in time and identifies the dwarf galaxy, named LKH, as a significant early building block of our home galaxy.