Milky Way v Andromeda: what happens when galaxies collide?
Nasa confirms that our galaxy is doomed to crash into Andromeda... in just four billion years
THE MILKY WAY is on a collision course with our neighbouring galaxy Andromeda, Nasa astronomers confirmed today.
There has been nearly a century of speculation about the future of Andromeda, also known as M31, and the Milky Way. Now scientists have used the Nasa Hubble Space Telescope to repeatedly measure Andromeda's motions over a seven-year period to give a more accurate prediction.
When the two crash into each other, our galaxy will be transformed, with the Sun flung into a new region - but not for at least four billion years. And once the two galaxies collide it will take a further two billion years for them to merge completely. Another smaller galaxy, Triangulum, is also expected to join the cosmic pile-up, reports The Daily Telegraph.
So is this the end of the Milky Way? Despite galaxies having hundreds of billions of stars, there is a huge distance between them. This means the galaxies could pass through one another without their stars colliding. But as the space in between is full of gas and dust, materials from one galaxy can cause radical changes in star formations of the other.
While scientists predict that Earth and our solar system are in no danger of being destroyed, the Sun could be flung into a different orbit and we could end up in a larger elliptical-shaped galaxy.
"In the worst-case-scenario simulation, M31 slams into the Milky Way head-on and the stars are all scattered into different orbits," says scientist Gurtina Besla of Columbia University in New York. "The stellar populations of both galaxies are jostled, and the Milky Way loses its flattened pancake shape with most of the stars on nearly circular orbits. The galaxies' cores merge, and the stars settle into randomised orbits to create an elliptical-shaped galaxy."
Then again, perhaps the whole collision can be avoided if, as one Daily Mail reader suggests, George Osborne can persuade Andromeda to do a U-turn. ·