Andromeda went bang at the dinosaur's time...

It was punched through by another nearby galaxy, known as M32...

Just imagine the two galazies getting closer, slowly being distorted by their reciprocal gravitational attractions, and shockwaves of matter and energy being blasted all around at terrific speeds...

dust ripples from the collision have been discovered in the infra red...



and this isn't all...

Since Andromeda is "only" 2 million Light Years away, and we (aboard the Milky Way) are heading straight to it, in a few billions years we'll have another big impact... the two galaxies will merge into an elliptical one... :-) I wish I were there to see the event... may be a bit accelerated, since a collision which takes some ten million years to happen may become a bit boring after a while...