Hubble Photographs 'Cartwheel Galaxy' Created From Violent Galactic Collision
In the meantime, we can see the results of other galaxies crashing into each other. Which is what the Hubble Space Telescope recently did when it captured a photo of ESO 350-40, which is more creatively nicknamed the "Cartwheel Galaxy".
If you're curious why it got that nickname, this is why:
#HubbleFriday The cartwheel shape of this galaxy is the result of a violent galactic collision. A smaller galaxy passed right through a large disk galaxy and produced shock waves that swept up gas and dust and sparked regions of intense star formation: https://t.co/pTNAK6kVcd pic.twitter.com/C3Mx3uK3bk— Hubble (@NASAHubble) January 19, 2018
At some point in the Cartwheel Galaxy's past, between 100 and 200 million years ago, a small galaxy and a much larger galaxy violently smacked into each other. The enormous outer ring, which is roughly 1.5 times the size of the Milky Way, was formed from the shockwaves of that collision, and stretched out into the blue areas of intense star formation that you can see above.
Those blue areas of composed of very young stars, so the collision effectively created a sort of stellar nursery when the gas, dust and other cosmic matter got scattered outward.
If it was any closer, it might be easier to find, but being 500 million lightyears away means that we need special equipment for a clear view of a galaxy that's 150,000 lightyears in diameter. It lies in the middle of the Sculptor constellation, if you want to have a general idea of where in the night sky it lies.
The photo itself dates back some time, but NASA and the ESA (who jointly operate the Hubble telescope) decided to re-release it after touching up the image, making a lot more details visible than ever before.
In about four billion years from now, a galactic collision will be happening much closer to home, when the Andromeda galaxy will violently barge through our own Milky Way. And once the collision begins, simulations of the collision predict that it'll take another six billion years before the merger is complete.
Earth will survive the impact - whether or not we humans will be on it is an entirely different story - so whoever's currently on the planet's surface will get an inside look at the entire cosmic event. It won't look much like the Cartwheel Galaxy, forming a massive but less spectacular spiral shape.
So for now, just enjoy watching this sort of thing from a safe distance. It won't always be that distant.