In 1941, Swiss astronomer Fritz Zwicky discovered what he called “one of the most complicated structures awaiting its explanation on the basis of stellar dynamics.” Enter the Cartwheel Galaxy.

Located a staggering 500 million light-years away in the Sculptor constellation, this ring galaxy is the aftermath of an intergalactic collision – the universe's version of a fender bender. It’s thought that this galaxy was once your standard spiral shape, but was transformed by a head-on “bulls-eye” crash with a smaller companion galaxy. When the smaller galaxy passed through the Cartwheel Galaxy, the force caused a powerful, gravitational shockwave that created a starburst around the centre.

Word on the cosmic street is that the Cartwheel Galaxy is finally starting to recover from the collision and retake its original, spiral form.