>>10959895Anon, they're called dark because no one is definitely sure what they are, but everyone is pretty sure there's "something" there.
If you walked around blind, and tripped over something, you wouldn't just assume that thing was some bullshit made up by scientists because you can't see it, because it just undoubtably fucked your shit up.
You don't know WHAT it is, but you know it's SOMETHING.
Galaxies behave like they have more mass than we can see, the mass we can't see is called dark matter.
If you assume there is some kind of matter that doesn't interact with the electromagnetic spectrum but does interact with gravity, so you'd look for places where gravity lensing is happening where there doesn't seem to be enough baryonic matter to do it. If you find that, then you're left to surmise that dark matter is more fact than fiction.
The real bitch is trying to figure out just what it is.
