A thought about the Milky Way
The Milky Way is our own galaxy. What exactly is it?
According to astronomers it is a Super-sized Black Hole somewhere in the center. Everything rotates around that center. We are at least on the second or third such rotation around the center.
The center sucks stars into it as they approach the black hole. Thus the center becomes denser as time goes on. The outer legs show signs of running cold creating an exceptional amount of matter.
All of this rotation must be a product of huge gravitational wells within the black hole. In other words the black hole is rotating.
That rotation does not really make sense unless the black hole itself is orbiting an even bigger black hole somewhere in space. Somewhere there must be an even bigger black hole that all the galaxies are rotating around. No one knows how big a gravitational pull would be necessary to make that happen.
Which brings up another question: How big a black hole can space contain? Is there a limit to the size of a big hole? At what point do you reach this critical size if there is one? What happens at critical mass?
What happens to the matter thrown off by the spin? Does it reach orbit status and gradually come back within range of the Center Hole? Or does it gradually get attracted by Stars within the legs of the galaxy? The black areas between the legs might hold huge amounts of cold matter. As the stars rotate around the core then they pick up all sorts of smaller and older debris.
This brings up the next question: What if one of these bodies floated into the gravity of the Sun? Would we gain another planet around the Sun? Space is very big. It might only happen once in a very great while. Could that be how Venus came to be where it is in our Solar System?
Or how about the many moons around the outer planets. Where did they originate from?
All of this depends on the answers we discover in the next few years as our instruments get better and better in observing the known universe. That is why we need to fund them.