“Hiding in Plain Sight” –Milky Way’s Ancient Merger With Fossil Galaxy Gaia-Enceladus

  ESA’s Gaia mission has made a major breakthrough in unravelling the formation history of the Milky Way.  Instead of forming alone, our Galaxy merged with another large galaxy early in its life, around 10 billion years ago. The evidence is littered across the sky all around us, but it has taken Gaia and its … Continue reading “Hiding in Plain Sight” –Milky Way’s Ancient Merger With Fossil Galaxy Gaia-Enceladus