Ancient Milky Way Merger

Ancient Milky Way Merger

About 12 billion years ago, a dwarf galaxy known as LKH collided with a young Milky Way and merged with it. This artist’s concept portrays that collision. NASA’s Hubble Space Telescope uncovered definitive evidence of this collision by studying globular star clusters.NASA, ESA, Joseph Olmsted (STScI) This artist’s concept, released on Aug. 17, 2026, depicts a collision between our Milky Way galaxy and a dwarf galaxy known as LKH that happened ab…

Astronomers discover a lost galaxy buried in the Milky Way’s ancient star clusters

The Milky Way absorbed a large dwarf galaxy about 12 billion years ago, pushing the known history of major galactic mergers much farther back in time. Hubble observations of ancient star clusters revealed a distinct population that could not have formed in either the early Milky Way or the later Gaia-Sausage-Enceladus merger. The discovery gives astronomers a new way to reconstruct the Milky Way’s earliest growth and may help separate stars born…