Stumbled upon

Based on what the experts spout in documentary television shows, every galaxy in the universe is moving away from us, and from each other. If that's the case, then how can some galaxies still manage to collide? I don't know enough about astronomy to work this one out.

OC3D

YouTube recommended a Laser Origami video. I watched it and then clicked on this related 3D Printed iPhone Case with Moving Gears! video.

The only thing going through my mind is, "Turn the 4th one right-side up to match the others, you dolt!"

The art of 3D printing is lost by my OCD.