Dark Matter (Also called Aether, Glitch Matter, or Fragments of Creation) is a form of matter making up 85% of the universe. While at first, it's existence was only implied based on astronomical observations, it's existence was proven to humanity in 2176 with the discovery of Aethons. This particle is what is known to scientists as a WIMP (Weakly Interacting Massive Particle) as it is only affected by gravity and none of the other four fundamental forces.
Dark Matter is incapable of coalescing into astronomical bodies under known physics. This is mostly due to the fact that these particles do not interact with any forces besides gravity. When they accelerate towards a body, they merely fly through it. Aethons lack the means to form solid objects.
Detection
Since Aethons do not emit or absorb electromagnetic radiation, there is no way to observe them with the naked eye. The most common way to detect these particles is with ultra-sensitive gravity wave detectors, as these particles have a very low mass. The first of these ultra-sensitive detectors need to be placed in interplanetary space in order to detect these particles, as even a human within a mile of the detector would alter the results.
As time went on, however, the sensors were able to "filter" all of the noise interference to allow for these detectors to exist on planets. Currently, these detectors are used on various harvesting ships to detect pockets of the substance.
Uses
Dark Matter is used mostly for creating artificial gravity. This is done by encasing it in a warp bubble. Dark Matter is usually fed into black holes to increase their mass, essentially allowing for things such as Birch Planets or Penrose Spheres to be much larger than what would usually possible.
Directly using it as a source of gravity rather than feeding it into a black hole is less common, but still used. This method, however, requires the Dark Matter to be kept in a warp bubble constantly. This is expensive and not as practical as a black hole, so this is less commonly used.