Dark matter is notoriously antisocial, refusing to interact with light and "normal" matter, making it effectively invisible. But what scientists aren't sure about is if dark matter interacts with itself.
If whatever particles make up dark matter do self-interact by colliding, and possibly even annihilating one another, new research suggests that clusters of galaxies could be used as natural dark matter colliders. This dark matter detection method would hinge on two of these vast groupings of galaxies meeting and smashing into each other.
