Astronomers have long thought that our galaxy, the Milky Way, would merge with our neighboring galaxy, Andromeda, within 5 billion years. But new simulations suggest that the odds of that collision happening are about the same as flipping a coin—at least in the next 10 billion years.
“I would say that the popular narrative has weakened, but not completely disappeared,” Manasvi Lingam, Astrobiologist “It’s a very interesting study,” a Florida Institute of Technology researcher not involved in the new study told Space.com.
About 2.5 million people Light years On our planet, Andromeda GalaxyAlternatively, Messier 31 is the closest large galaxy. Milky Way. By studying the movements of Andromeda Signs from the light it emitsAstronomers first predicted in 1912 that a galaxy would collide with our own, approaching at 68 miles per second (110 kilometers per second). Later studies Guaranteed The two galaxies collided head-on and were locked in a cosmic dance, eventually merging into a single elliptical galaxy, which was named “Milkomeda.”
Such mergers were common occurrences 6 to 10 billion years ago, shaping the galactic landscape of our universe. Our galaxy is A remnant of past cannibalismThe new study suggests that measurements of the two galaxies’ positions, motions, and masses are not strongly constrained, making it difficult to predict their fate with certainty—even with the most precise observational data yet from astronomers. Til Sawala At the University of Helsinki, Finland.
relevant: Andromeda Galaxy Collision Triggers Massive Galaxy Migration 2 Billion Years Ago
Previous studies also did not adequately account for the gravitational effects of a nearby, smaller galaxy, which could have a “clear and fundamental” impact on the Milky Way-Andromeda orbit and be strong enough to push the two galaxies off a collision course, the new preprint shows. paper. This uncertainty leaves room for “dramatically different outcomes,” and a 50 percent chance that there will be no collision between the two galaxies, the researchers wrote. “At present, claims of our galaxy’s imminent demise appear to be greatly exaggerated.”
Using recently collected observations of nearby galaxies, Gaia Sawara and his colleagues used the Hubble Space Telescope to simulate possible scenarios for the evolution of the Local Group of galaxies, which includes our Milky Way and Andromeda along with several other galaxies.
If your simulation includes: Triangulum Galaxy (M33) — the second-largest member of our galactic neighborhood — has a high probability of merging. But when we incorporated orbits into the simulations, Large Magellanic CloudResearchers found that for galaxies running perpendicular to the orbit linking two doomed galaxies, a merger is unlikely to occur within the next 10 billion years.
“If there is no merger, the two galaxies will pass each other at some distance,” Lingam said. Depending on how far away that distance is, some of the outer regions of each galaxy may be torn apart and thrown away. space. The new study still allows for a 50 percent chance of an impact, but Lingam emphasized that this is not an insignificant probability. He said that even if a full-blown collision were to occur, the direct impact on a single-planet system like ours would be small. “But I have to say that at this stage, there is still a lot that is unknown.”
Upcoming data being generated by the Gaia mission The best map of the galaxy It will provide better estimates of the motion and mass of our galaxy to date. The data could help astronomers figure out which of our neighboring galaxies is the dominant influence in a possible merger.
If the two galaxies collide billions of years from now, astronomers predict: Solar System You will be thrown into one of the outer arms of the newly merged galaxy. star When launched into space, it leaves behind a spectacular tail of gas and dust that are compressed. cloud It will cause a burst of star formation. The two galaxies will merge without much chaos, as there is a lot of empty space inside them. Our accelerating universe will pull the distant galaxy further away from us, and after about 10 billion years after the merger, Milkomeda will become our entire visible universe.
By then, humanity will have long since died out. earthBecause our expanding sun will render our planet uninhabitable long before its long-awaited demise.
This paper can be viewed as follows: Preprint It is stored in the paper repository at arXiv.
