What is dark matter? Even for astrophysicists, it's a question that remains unanswered. These invisible particles make up most of the matter in the universe and about a quarter of the universe as a whole. They are thought to be the cosmic glue that binds the universe together, but we still don't know what kind of particle they are. Finding the answer to that question could provide us with an unprecedented understanding of the past, present and future of our known universe.
