The Milky Way swallowed a smaller galaxy about 11.8 billion years ago

The Milky Way, a ⁠large and spiral-shaped galaxy that is home to hundreds of billions of stars including our sun, has taken a long and complicated path to achieve its current dimensions, as illustrated by new research documenting a milestone event early in its history.
Scientists observing clusters of stars congregated near the Milky Way’s centre have discovered evidence that our galaxy swallowed a smaller galaxy roughly 11.8 billion years ago, when the universe was less ‌than 15 per cent of its...