You may have heard that the days of our home galaxy, the Milky Way, are numbered.
The Milky Way is one of the dominant galaxies of a cluster known as the Local Group. The other major player in the group is the Andromeda nebula (M31). And according to recent measurements by the Hubble Space Telescope, the two galaxies are traveling through space and dark matter headed directly toward each other.
“After nearly a century of speculation about the future destiny of Andromeda and our Milky Way, we at last have a clear picture of how events will unfold over the coming billions of years,” says Sangmo Tony Sohn of the Space Telescope Science Institute in Baltimore. His colleague Roeland van der Marel confirms the research: “Our findings are statistically consistent with a head-on collision between the Andromeda galaxy and our Milky Way galaxy.”
The galaxies will lock horns in a couple billion years when their central supermassive black holes converge. Watch the simulation from The New York Times, via NASA and the European Southern Observatory, here.
The situation may sound a little odd to those of us who are aware that in general, with the universe expanding, galaxies are spreading farther and farther away from each other over time. However, in our own neighborhood, mutual gravity constrains them. When the Milky Way and Andromeda finally meet, the stars will rearrange themselves and form a new mega-galactic union. The celestial fireworks should be amazing.
The universe could even experience a threefer, as the Triangulum Galaxy (M33, the third largest and brightest galaxy of the Local Group) will likely join in this event.
Although we’re confirmed apocaloptimists here at PlanetSave, we cannot sum up the situation better than the elegant Times:
“The bad news is that we will be dead. Earth will have been boiled and sterilized eons earlier as the sun brightens. The good news is that the collision will be a fiesta of new stars forming as that disruptive gravity collapses and then condenses clouds of gas and dust. New worlds, another chance. Maybe.”