When two galaxies collide, astronomers witness a frenzy of star formation creating what are known as "starburst galaxies." Although this is known, it's a little counter-intuitive; during galactic mergers, the swirling interstellar gases are so turbulent that star formation should be switched off. So what's going on?
VIDEO: We've Simulated The ENTIRE Universe
Using two of Europe's most powerful supercomputers, French astrophysicists simulated 300,000 light-years of interstellar gas inside a Milky Way-like galaxy (on the TGCC Curie supercomputer in France) and a volume of gas, 600,000 million light-years wide, inside two merging galaxies (on the SuperMUC supercomputer in Germany). Committing millions of hours of computational time, the simulation replicated the random motions of gas inside the galactic disks, resolving chaotic features fractions of a light-year across.