Dark Matter, component of the universe whose presence is discerned from its gravitational attraction rather than its luminosity. Dark matter makes up 30.1 percent of the matter-energy composition of the universe; the rest is dark energy (69.4 percent) and “ordinary” visible matter (0.5 percent).
Dark matter is composed of particles that do not absorb, reflect, or emit light, so they cannot be detected by observing electromagnetic radiation. Dark matter is material that cannot be seen directly.