National Solar Observatory/Sacramento Peak
Filament

       Bigger  Smaller

Types: Universe     ---- Filament   ---- Superclusters

Size:  2000 Mpc/h   ---- 100 Mpc/h  ---- 50 Mpc/h

Earth: (Universe)   ---- (Filament) ---- Local Supercluster

On length scales of about 50 - 100 Mpc/h the galaxies in the Universe appear concentrated in elongated structures called "filaments" which seem to form an interconnected network on the interfaces between voids. Local large-scale concentrations of galaxies in filaments are called superclusters.

The image shows a computer simulation of what the universe may currently look like on very large scales. The displayed cube measures 170 Mpc/h (with h assumed equal to 0.5). The density of the gas is indicated by its color in the image: high-density gas (density up to 100 times the average) is shown as red and opaque, while low-density gas is shown as blue and transparent.

The model assumed in the calculations is the cold + hot dark matter (CHDM) or mixed dark matter (MDM) model. Galaxy formation is not included in the model, but it seems reasonable to assume that the galaxy density would be highest where the gas density is highest, too. For more information and movies about the simulation, see at http://zeus.ncsa.uiuc.edu:8080/chdm_script.html.

[LS 6 January 1998]