Billions of years from now, the night time sky will glow with stars, dust, and gasoline from two galaxies: the Milky Way, wherein we stay, and the encroaching Andromeda Galaxy (M31). Credit score: Lynette Cook dinner for Astronomy journal.
The Andromeda Galaxy is approaching the Milky Way at almost 1 / 4 million miles per hour. It’s the closet main galaxy to our Milky Way and is essentially the most distant factor you possibly can see with the bare eye at 2.5 million gentle years away. Absolute chaos will start as the 2 galaxies strategy one another, ultimately changing into Milkomeda. The whole lot will seem like a large pinball recreation, with enormous quantities of rocks, dust, asteroids, planets, and stars being thrown in all instructions.
Till 2012, it was not identified whether or not the collision was undoubtedly going to occur or not. Researchers, using Hubble to track the motions of stars in Andromeda with unprecedented accuracy, concluded the galaxies would collide in about 4 billion years. Such collisions are comparatively widespread, contemplating galaxies lengthy lifespans. In accordance with simulations, the remnant will seem like an enormous elliptical galaxy, which is a blob-like galaxy with out discernible spiral arms or an inner construction.
Andromeda galaxy accommodates about one trillion stars and the Milky Way accommodates about 300 billion. The celebs concerned are sufficiently far aside that it’s extremely unbelievable that any of them will individually collide. For instance, the closest a part of the Solar is Proxima Centauri, which is about 4.2 gentle years away. If the Solar had been a ping pong ball, then Proxima Centauri can be a pea about 680 miles away. Though stars are extra widespread close to the facilities of every galaxy, the typical distance between stars remains to be 100 billion miles. That’s like inserting one ping-pong ball each two miles; thus, it’s extraordinarily unlikely that any two stars from the merging galaxy would collide, however some stars is perhaps ejected.
What occurs to the black holes after the Andromeda and Milky Way collision?
The Milky Way and Andromeda every include a central supermassive black hole. These black holes will ultimately spiral into each other and converge close to the middle of the newly shaped galaxy over a interval which will take hundreds of thousands of years. When the supermassive black holes come inside one gentle 12 months of one other, they are going to start to strongly emit gravitational waves that can radiate additional orbital power till they merge fully. Fuel taken up by the mixed black holes may create an lively galactic nucleus. If this occurs it could launch an inconceivable quantity of power.
OK, so what’s the way forward for our solar system?
Primarily based on present calculations, scientists predict a 50% probability that in a merged galaxy the solar system might be swept out 3 times farther from the galactic core than its present place. Our galaxy is organized into spiral arms and the Solar is in a department referred to as the Orion Spur. If we had been to be flung farther out, meaning our solar system would land simply on the fingertips of this arm. Scientists additionally predict someday throughout the collision, there’s a 12% probability that the solar system could possibly be completely ejected from the newly shaped galaxy. For some reassurance, humanity can be lengthy passed by then, in fact. Such an occasion would really haven’t any antagonistic impact on the solar system and the possibilities of any kind of disturbance to the Solar or planets themselves could also be distant, that’s excluding planetary engineering.
By the point the two galaxies collide, the floor of the Earth may have already turn into far too scorching for liquid water to exist, as a result of progressively growing luminosity of the Solar, ending all terrestrial life, however our planet will nonetheless be caught in the course of this collision and its view of the universe won’t ever be the identical. If we may nonetheless see the night time sky nonetheless, whether or not kind the hellish perspective of Earth or from the far reaches of the outer solar system, Andromeda can be rising bigger within the sky and ultimately about 4 billion years from now, it may probably stretch from horizon to horizon like a serene rainbow of dew.
