Even worse than two galaxies colliding is the collision of clusters of galaxies -- huge arrays of galaxies held together by the force of gravity. This is a photo from Hubble's web site. It shows the aftermath of just such a collision. Here is their description:
"A powerful collision of galaxy clusters has been captured by NASA's Hubble Space Telescope and Chandra X-ray Observatory. The observations of the cluster known as MACS J0025.4-1222 indicate that a titanic collision has separated the dark from ordinary matter and provide an independent confirmation of a similar effect detected previously in a target dubbed the Bullet Cluster."
It's all about the dark and normal matter separation -- which is wildly important; don't get me wrong. But the possible toll on life is never even considered because we're busy making believe that we're the only intelligent life in the universe. This is a colossally idiotic notion. No one will ever convince me that numerous intelligent civilizations weren't destroyed in this and similar collisions. What a colossal waste of evolution's work! It truly is an uncaring universe.
It's not a reach to assume that many life-bearing planets within these clusters collided with planets or suns or other debris. At best, they were turned into molten rock and the civilizations on the surface were subsumed into the planet itself, never to be heard from or known again. They might as well have disappeared into a black hole.
An uncaring universe, indeed. More reason to be overjoyed with our luck as we find ourselves in a peaceful neck of the woods. We are truly blessed -- by chance. But what of those civilizations? I often think of them as I fall asleep at night, and I pay them mental tribute. We will never know them and that is so sad.
