The ESO's 'Very Large Telescope' Captures Two Galaxies Undergoing a Very Close Encounter
But a pair of galaxies recently photographed by the Very Large Telescope in Chile (which is operated by the European Southern Observatory) may be a rarer instance of galaxies brushing against each other without a definitive collision and eventual merger at the end. Hopefully, at least - astronomers aren't entirely sure what the galaxies NGC 5426 and NGC 5427 are going to do just yet.
These two galaxies, collectively known as a cosmic event called Arp 271, are locked in a gravitational embrace that's about 130,000 lightyears in length and about 110 million lightyears away from us. See it below:
Last photo from #VIMOS before decommissioning: two interacting galaxies. Active on VLT for 16 years, VIMOS collected spectra of galaxies, showing how they formed, grew, and evolved. Credit: @ESO /Juan Carlos Muñoz https://t.co/ZxEzJmr2LH pic.twitter.com/S4bklkJHHH— ESO (@ESO) May 21, 2018
While it is possible that they'll simply pass each other by without getting sucked into each other's gravity permanently, they won't be exactly the same if they do separate. Some tails of the galaxies have already been ripped off to form a connecting tissue of cosmic dust and materials between the two, and they'll likely both look a little distorted after the fact.
On the other hand, if the two galaxies of Arp 271 do end up colliding, they'll likely end up merging into a single galaxy that will also look slightly distorted even if its shape remains otherwise normal. They may actually have already began merging by now, since we'll always be 110 million lightyears behind their progress just because of how long it takes light to reach us.
This image also has other significance - while the Very Large Telescope is still busy watching the stars, this is the last photo it took using its VIMOS tool (short for "VIsible Multi-Object Spectrograph"). Instead of focusing on a single object, VIMOS could capture multiple galaxies in detail simultaneously, but it was finally decommissioned on March 24, 2018, and this final photo was released a few months afterward.
We may never know if Arp 271 will end up in a mass collision, but hopefully not. We don't want them to end up like us when the Milky Way and Andromeda galaxies eventually crash into each other.