Sort of.

We have a lot of data that requires something like dark matter to exist. There’s a bunch of matter, and it moves in a way that requires way more matter than what we can see. We can detect gravitational effects pretty much everywhere that greatly exceed what we’d expect from the matter we detect. We can detect this so well that we have intergalactic maps of where this extra matter must be.

We just… don’t know what it is. We’ve basically ruled out all the stuff that we know about. And problematically, everything at small scales like what we deal with in the solar system seems within what we’d expect with normal matter. But when we look farther out, stuff acts like there’s way more gravity than there otherwise should be.