Explanation: Two galaxies are squaring off in Corvus and here are the latest pictures . When two galaxies collide , the stars that compose them usually do not. That's because galaxies are mostly empty space and, however bright, stars only take up only a small amount of that space. During the slow, hundred million year collision , one galaxy can still rip the other apart gravitationally, and dust and gas common to both galaxies does collide . In this clash of the titans , dark dust pillars mark massive molecular clouds are being compressed during the galactic encounter , causing the rapid birth of millions of stars, some of which are gravitationally bound together in massive star clusters .