I've read several articles online that state that our galaxy will collide with a neighboring galaxy in the future, but there is no evidence about it happening.


After reading a few articles on the topic, I started to wonder:

  • When will it happen?
  • Which galaxy will collide with our own?
  • Is it even going to happen?

(your post should answer all three)

It's a scary but oddly interesting theory, and a little enlightenment would be much appreciated! :)

Not a duplicate--

I'm asking if the possibility that any galaxy will collide with our own, not just one.

  • $\begingroup$ It's a scary Not unless you expect to live an extraordinarily long time. :-) $\endgroup$ – StephenG Feb 7 '18 at 20:02
  • $\begingroup$ Even if some sort of humans were alive when the merger took place, the distance between stars is so great that the likelihood of any particular system being affected is so small as to be negligible, though their night sky would look much different. $\endgroup$ – BillDOe Feb 7 '18 at 20:47
  • $\begingroup$ Is it even going to happen? Yes. Galaxies collide all the time. Smaller dwarf galaxies have collided with the Milkyway in the past and will again. It's not a "theory" in layman's terms so much as an evidenced backed (I hate to use the word certainty), but it's pretty darn close to a certainty. $\endgroup$ – userLTK Feb 7 '18 at 23:22
  • 1
    $\begingroup$ We have some smaller dwarf galaxies around us, they will collide. Then there is the Andromeda galaxy, also it will collide. Nothing catastrophal will happen - the stars are very small, compared to the distance between them. Imagine a raspberry in Richmond and another in Washington DC. So far away are the stars, compared to their size. Today, in our region, stars are roughly 2-6 light year away from their nearest neighbor, after the merging (and not collision) they will be 1-3 light year away. The Voyager space probe, the most far human-made object, is around 0.001 light year away from us... $\endgroup$ – peterh - Reinstate Monica Feb 7 '18 at 23:35
  • $\begingroup$ The whole process will last some hundred million years long. After that, we will have a single, bigger, not so well-looking galaxy, like this: whillyard.com/science-pages/images/ngc-4449-irregular.jpg $\endgroup$ – peterh - Reinstate Monica Feb 7 '18 at 23:37

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