It has become obvious to NASA that one day our Milky Way Galaxy will become engulfed by the Andromeda Galaxy. While they once predicted it would be around another 4 billion years before that happened, a halo of hot gas has been discovered which would mean that our galaxies are already touching.
An astrophysicist from Notre Dame, named Nicholas Lehner recently led a team of researchers using the Hubble Space Telescope to identify a massive halo of hot, ionized gas around 2 million light years in diameter that surrounds the galaxy.
If Andromeda was actually close enough to touch us, then it is much closer than anyone has previously predicted. Furthermore, despite it just being a halo that is touching, we could have two completely different galaxies beginning to combine gasses and molecules.
Lehner, who describes halos as ‘gaseous atmospheres of galaxies,” studied the halo by seeking out quasars that are similar to stars. However, they emanate a massive amount of energy as matter finds its way into supermassive black holes in their cores.
“As the light from the quasars travels toward Hubble, the halo’s gas will absorb some of that light and make the quasar appear a little darker in just a very small wavelength range,” said J. Christopher Howk, associate professor of physics at Notre Dame and co-investigator. “By measuring the dip in brightness, we can tell how much halo gas from M31 there is between us and that quasar.”
And when the two do eventually collide, what will follow will be completely out of this world. A variety of timelines has found their way onto the internet thanks to scientists. Apparently, when it begins, it will start an apocalyptic chain of events that will last for billions of years, until the two merge and become another galaxy. Before this happens, however, humanity will be able to see the galaxy up close and personal. The view will be spectacular. When they merge, after billions of years, the supermassive black holes in each galaxy will collide devour one another.
If you have never heard of anything similar to this, it may sound like something straight out of a science fiction movie. However, there is nothing fiction about the merging of galaxies. Back in 2009, scientists were able to capture images from space of two spiral galaxies that were in the early state of merging. Thankfully, this is something we probably won’t be around for, as it would be a 6 billion year process. Scientists predict that we will have disappeared in the Sun by then.