Milky Way-Andromeda Collision Far Less Certain

New research published in Nature Astronomy has revised predictions about the future of the Milky Way and Andromeda galaxies, showing that a collision is far less certain than previously believed. Simulations using data from NASA's Hubble and ESA's Gaia telescopes, with updated measurements and the gravitational effects of neighboring galaxies, estimate only a 2% chance of a merger within 5 billion years and about a 50% chance within 10 billion years. This contrasts with older projections of a nearly inevitable collision in 4–5 billion years. The findings indicate that the galaxies might instead orbit each other for tens of billions of years without merging. Any potential collision would likely occur long after the Sun has died and Earth has become uninhabitable. The study challenges the long-held assumption that a merger is the Milky Way's certain fate.