Arcetri Astrophysical Observatory

Evidence of a massive accretion event 1.8 billion years before the Gaia-Sausage-Enceladus merger

Abstract The merger history of the Galaxy has been traced back firmly to a redshift of 2 (10 billion years ago). While evidence for the existence of at least one more substantial merger before this time has been presented, its interpretation is yet to be fully established. Here w...