Universe's dark matter, 3D map from the Hubble Cosmic Evolution Survey (COSMOS). This survey mapped the location of normal (baryonic) matter (R980/222) and dark matter (R980/223) in a region of the sky. This 3D map traces the change in dark matter from the early universe (right) to the present day (left), which is more clumpy. Dark matter is a form of matter thought to comprise the bulk of the mass of the universe. Its presence can be inferred from the gravitational distortion of normal matter and light. This was the largest ever survey undertaken with the Hubble Space Telescope. This region of the sky is in the constellation Sextens. The results were published in January 2007.