See what the grim darkness of the future holds for the Warhammer 40,000 universe in the realm of video games.
Dark matter is hidden from our view making it difficult to study. Despite making up roughly 80 percent of all matter, we can't see it, touch it, or directly detect it with any of our instruments. It doesn't emit, absorb, or reflect light, making it completely invisible, and we only know it exists because of its gravitational effects on visible matter. The idea was first proposed by Fritz Zwicky in 1933 whilst studying the Coma Cluster. He noticed that the galaxies in this group were moving far too quickly to be held together by gravity alone.

