The destined collision of the Milky Way and Andromeda may not happen
Astronomers have long anticipated a cosmic collision between the Milky Way and the Andromeda galaxy. This event, expected to occur within the next 5 billion years, has been seen as an inevitable galactic merger. However, a recent simulation suggests that the chance of this collision occurring within the next 10 billion years may be less certain than previously thought. According to a new study led by Till Sawala of the University of Helsinki, the chance of the Milky Way and Andromeda colliding may be as low as 50%.
The Shift in Predictions
Previous studies based on the motion of Andromeda and the orbit of the Milky Way had confidently predicted a head-on collision. But the latest researchwhich includes data from the Gaia and Hubble Space Telescopes, shows that the gravitational influence of smaller nearby galaxies could significantly alter these predictions. These smaller galaxies could potentially deflect the Milky Way-Andromeda encounter, making the collision scenario less likely. As a result, the idea of an impending galactic merger is now considered less definitive.
Simulation insights
The new simulations included several cosmic factors, such as the influence of the Triangulum Galaxy and the Large Magellanic Cloud. The results showed that while the merger scenario still has a 50% chance, it is not a certainty. The presence of these additional galaxies could increase or decrease the chance of a collision, depending on their gravitational effects on the Milky Way-Andromeda system.
Possible outcomes
If the collision does not occur, the galaxies could pass each other at a safe distance. Even if a collision did occur, the effects on our solar system would likely be minimal. The merger would primarily affect the outer regions of both galaxies, potentially disrupting some galaxies but leaving the core regions relatively untouched.
Future research
Upcoming data from the Gaia mission, which aims to provide a detailed map of the Milky Way, could help refine these predictions. With more precise measurements, astronomers can better understand the factors that influence the interaction between the Milky Way and Andromeda.
In summary, while the potential collision remains a possibility, recent findings suggest the scenario is less certain than once thought.
