What are the chances of the Milky Way and Andromeda colliding?

There is a 50% chance that our galaxy, the Milky Way, will collide with its neighbor Andromeda galaxy within the next 10 billion years. This is the conclusion reached by an international team of scientists from Finland, France, and the UK. They have published their findings on the arXiv portal, which hosts non-peer-reviewed scientific papers.The Andromeda galaxy, located 2.5 million light-years from the Milky Way, is slowly approaching us at 110 kilometers per second. Astronomers have long believed that our galaxies would inevitably collide and eventually merge, forming a new, single galactic system.However, a new study has shown that this scenario is not inevitable. The scientists said that uncertainties in the data about the current positions, movements, and masses of all the galaxies leave room for a variety of outcomes. In particular, the probability that the merger of the Milky Way and Andromeda will not occur is about 50%.The researchers also noted that previous models did not take into account an important factor - the gravitational influence of smaller galaxies within the Local Group, to which both the Milky Way and Andromeda belong. This influence can change the trajectories of galaxies and prevent their collision.For their calculations, the scientists used data obtained using the Gaia and Hubble space telescopes. They estimated the masses, speeds and gravitational interactions of the four largest galaxies of the Local Group: the Milky Way, Andromeda, the Triangulum Galaxy and the Large Magellanic Cloud. Then this data was entered into a computer model, which showed possible scenarios for the future development of events.Thus, the probability of a collision between the Milky Way and Andromeda can be compared to tossing a coin. If the merger does occur, it will not happen earlier than in 8 billion years.