"Cosmic butterfly": The Gemini North telescope captures a spectacular scene created by the collision of two galaxies

The Gemini North telescope in Hawaii has captured a stunning image of two colliding galaxies, located around 180 million light-years from Earth.

The galaxies, known as UGC 12914 and UGC 12915, have been nicknamed the "Taffy Galaxies" due to their twisted and stretched shape, which resembles a piece of candy.

The collision between the galaxies, which began around 25 million years ago, has triggered both star formation and star halting. The mixing of material from two galaxies can give birth to giant molecular clouds that become sites of intense star formation. However, collisions can also create regions where stellar birth is curtailed.

The image captured by the Gemini North telescope shows the galaxies as they recover from their head-on smash and draw away from each other. The region is composed of strands of red and brown hydrogen clumps and molecular gas filaments, which stretch as the galaxies separate.

The intergalactic bridge joining the galaxies is full of the building blocks for star formation, but the birth of stars is halted by violent churning and heating. The high-velocity gas pulled from each galaxy created a massive gas bridge between them with turbulence throughout the bridge, prohibiting the clumping and compression of gas into dense patches needed to birth new stars.

Galaxies collide in a variety of ways 

Galaxies can collide in various ways, resulting in different outcomes. In some cases, the spiral arms of larger galaxies can be drawn towards smaller satellite galaxies, eventually leading to a collision. Alternatively, small galaxies can collide with larger galaxies when their orbits intersect with the larger galaxy's main body, causing significant distortions to both galaxies' structures.

If both colliding galaxies lack the momentum to carry them away from the merger, they will mix and merge. As the clouds of gas in these galaxies interact, the gas can get compressed into dense patches, triggering star formation.

However, head-on collisions like the one seen between UGC 12914 and UGC 12915 in this image are different. Unlike the gradual merging of two "puddles," head-on collisions are more like two cups of water being dashed into the same bowl. For the Taffy Galaxies, this meant the galactic disks and gaseous components of both galaxies violently smashing right into each other, causing a massive injection of energy into the gas, making it highly turbulent.

As UGC 12914 and UGC 12915 recovered from this collision and drew away from each other, high-velocity gas was pulled from each galaxy. This created a massive gas bridge between them with the turbulence of the stellar material throughout this bridge now prohibiting the clumping and compression of gas into dense patches, which are needed to birth new stars.