Celestial firework marks nearest galaxy collision

17 agosto 2015

A spectacular galaxy collision has been discovered lurking behind the Milky Way. The closest such system ever found, the galaxy is only 30 million light years away. It has been dubbed «Kathryn’s Wheel» both after the famous firework that it resembles. Such systems are very rare and arise from «bulls-eye» collisions between two galaxies of similar mass. Shockwaves from the collision compress reservoirs of gas in each galaxy and trigger the formation of new stars. This creates a spectacular ring of intense emission, and lights up the system like a Catherine wheel firework on bonfire night.