Date: 20 November 2012
Satellite: Planck
Depicts: Numerical simulation of the cosmic web
Copyright: Image courtesy of Klaus Dolag, Universitäts-Sternwarte München, Ludwig-Maximilians-Universität München, Germany

This image shows how matter in the Universe is arranged on very large scales, forming a wispy network of clusters, filaments and voids known as the cosmic web. This image was extracted from a numerical simulation of the formation and evolution of cosmic structure.

The colour scale indicates the density of gas in the cosmic web: blue indicates regions where the density is lower than average, whereas white and red correspond to increasingly denser structures. Galaxy clusters form at the densest knots in this network, where filaments intersect.

The temperature of gas is higher in the denser portions of the cosmic web, ranging from about a million K in the blue regions to tens of millions of K in the white regions and hundreds of millions of K in the red regions.

The image shows a portion of the cosmic web that spans almost 900 millions of light-years across.