News Astronomy

The Milky Way may have grown up faster than astronomers suspected

Most of the galaxy’s disk was in place before a major collision 10 billion years ago

image of Milky Way

Much of the Milky Way’s characteristic disk (seen edge-on in this image from the Gaia spacecraft) was already in place 10 billion years ago, when an interloper galaxy called Gaia-Enceladus/Sausage collided with it.

DPAC/Gaia/ESA (CC BY-SA 3.0 IGO)

By Lisa Grossman

- More than 2 years ago

The Milky Way as we know it today was shaped by a collision with a dwarf galaxy about 10 billion years ago.