When we think of celestial threats to our planet, we usually think of big asteroids and comets, and maybe the odd gamma ray burst or supernova. What we probably wouldn’t think of is an entire galaxy bearing down on us, but according to a new study, that’s exactly what’s happening right now. The Large Magellanic Cloud (LMC), a nearby dwarf galaxy, is on a collision course with the Milky Way, but there’s no need to worry just yet – the starry smashup won’t begin for another two billion years or so.
But on closer inspection, astronomers have realized that a third scenario may be more likely. Recent studies have found that the LMC is much more massive than it looks, containing almost twice as much dark matter as was previously thought. That means it’s quickly losing energy, slowing down and being pulled towards the Milky Way.
To predict what happens next, a team led by researchers at Durham University used a supercomputer called Evolution and Assembly of GaLaxies and their Environments (EAGLE). This allows them to build realistic models of galaxies like the Milky Way and the LMC, and smash them together to see what happens.