The Milky Way and Andromeda’s future

The Milky Way and Andromeda move within the Local Group, but a future close encounter is not certain. Earlier models predicted a merger in roughly 4–5 billion years; newer simulations that account for uncertainties in galaxy motions and masses put the chance of a merger within the next 10 billion years at about 50%. Even if the galaxies interact, direct collisions between individual stars are unlikely because of the enormous distances between them.