The Milky Way could finally escape the premeditated collision with the Andromeda galaxy

2024-09-10 09:42:20

For years, astronomers thought that the Milky Way was destined to collide with its close neighbor, the Andromeda galaxy, within a few billion years. But a new simulation finds that a There is a 50% chance that the next accident will be a near missfor at least the next 10 billion years. Andromeda has been known to be heading towards our home galaxy since 1912, almost directly towards the Milky Way at a speed of 110 kilometers per second. These galactic mergers are extremely messy affairs, seen elsewhere in the universe. While most stars survive unscathed, the spiral structures of galaxies are destroyed, sending streams of stars into space. After billions of years, merging galaxies usually settle into a single elliptical galaxy: a giant, featureless blob of stars. A 2008 study suggested that a merger of the Milky Way and Andromeda was inevitable within the next 5 billion years, and in the process the Sun and Earth would be gravitationally captured by Andromeda for a time before ending up in suburbs in the far West. as an elliptical result, which the researchers named “Milkomeda.”

In the new simulation, the researchers used the latest and best estimates of the motion and mass of the four largest galaxies in the Local Group. They then subjected them to simulations developed by the Institute for Computational Physiology at Durham University. First, they ran the simulation including only the Milky Way and Andromeda and found that they merged in just under half of the cases, lower probabilities than other recent estimates. When they included the effect of the Triangular galaxy, the third largest in the Local Group, the probability of a merger increased to about two-thirds. But with the inclusion of the Large Magellanic Cloud, a satellite galaxy of the Milky Way that is the fourth largest in the Local Group, those odds were reduced to a coin toss. And if the cosmic collision happens, it won’t be for about 8 billion years. “As things stand, the announcements of the impending arrival of our galaxy appear to be greatly exaggerated,” the researchers wrote. Meanwhile, if the accelerated expansion of the universe continues unabated, all other galaxies will have passed beyond our cosmic event horizon, leaving Milkomeda as the sole occupant of the visible universe. available as a preprint in arXiv.