}}</ref> It is thought that this dark matter dictates the structure of the Universe on the grandest of scales. Dark matter gravitationally attracts [[baryon]]ic matter,<ref>Baryonic matter is matter as we know it.</ref> and it is this 'normal' matter that astronomers see forming long, thin walls of super-galactic clusters. | }}</ref> It is thought that this dark matter dictates the structure of the Universe on the grandest of scales. Dark matter gravitationally attracts [[baryon]]ic matter,<ref>Baryonic matter is matter as we know it.</ref> and it is this 'normal' matter that astronomers see forming long, thin walls of super-galactic clusters. |