A team of astronomers recently made the remarkable discovery of two galaxies colliding behind our Milky Way. The discovery is groundbreaking as it's the closest collision of star systems that has ever been found. The team, led by the University of Hong Kong's Prof. Quentin Parker and University of Manchester's Prof. Albert Zijlstra, has published their study in Monthly Notices of the Royal Astronomical Society.

The two galaxies are 30 million light years away, which is said to be relatively close to our system. The newly discovered galaxy, which has been named "Kathryn's Wheel" as homage to both the well-known firework that it resembles and to Prof. Zijlstra's wife, is seven times closer than any galaxy remotely similar to it and 40 times closer than the "Cartwheel" galaxy.

Systems like "Kathryn's Wheel" are said to be quite unique and are the result of "bulls-eye" collisions between two galaxies that have the same mass. The shock waves that come from the impact compress the pool of gas in each galaxy and start the development of new stars. This, in turn, creates the amazing ring of extreme emission and lights up a solar system the same way that a Catherine wheel firework would.

This discovery is crucial for while it's been proven that galaxies expand through collisions, the event is rarely seen as it occurs. And the chance of catching a bull's-eye collision that's currently happening is even rarer.

The galaxy was discovered during a special wide field survey of the Southern Milky Way while researchers were sifting through survey images while looking for the remains of dying stars in the Milky Way. The members of the research team were surprised when they saw the glorious cosmic ring behind the Milky Way in the constellation of Ara (the Altar).

According to Professor Parker, "Kathryn's Wheel" is close enough to our solar system to make it a prime candidate for more detailed studies.

"The ring is also quite low in mass - a few thousand million Suns, or less than 1% of the Milky Way - so our discovery shows that collision rings can form around much smaller galaxies than we thought," he added.

Meanwhile, Professor Zijlstra is thrilled with the discovery as it's not every day that one gets "to name any objects in the sky." He said that naming the new galaxy "Kathryn's Wheel" is appropriate since it does resemble the firework. And naming it after his wife also follows the tradition of naming objects in space after love ones.