Half the universe's missing matter has just been finally found


Half the universe's missing matter has just been finally found

However, the result doesn't account for all the visible matter that should be there, and about 90 percent of it seems to be missing.

The new study confirmed that the missing ordinary matter can be discovered in the form of filaments of these diffuse gasses, which link the galaxies.

Scientists believe most of the universe-about 70 percent-is made up of dark energy, the mystery force thought to be driving its expansion. Baryonic matter - part of what we contemplate "normal matter" in the universe -constitutes everything we are accustomed with, the stars, planets, the chair you are sitting on, the device you are using to read this, and you.

Hideki Tanimura is from the Institute of Space Astrophysics in Orsay; France led one of the teams.

The teams' work focused on the universe's ordinary matter, matter composed of protons, neutrons and electrons, as opposed to mysterious dark matter, which make up most of the known universe. The other team, from the University of Edinburgh, concluded that the figure was about six times the average density.

The reason behind this invisibility is that these baryonic matters very small and are not dense enough to block starlight or hot enough to provide a signature. Both teams of researchers used the Sunyaev-Zel'dovich effect concept and used data on pairs of galaxies taken from catalogs in the Sloan Digital Sky Survey.

As the light travels, some of it scatters off the electrons in the gas, leaving a dim patch in the cosmic microwave background - remnants from the birth of the cosmos. Since the tendrils of gas between galaxies are so diffuse, the dim blotches they cause are far too slight to be seen directly on Plancks map.

Both groups found confirmation that the gas in the areas they were studying were dense enough to form filaments, "definitive" evidence they existed between the galaxies.

"We expect some differences because we are looking at filaments at different distances", says Tanimura. "Everybody sort of knows that it has to be there", said Professor Kraft, "but this is the first time that somebody - two different groups, no less - has come up with a definitive detection". He said the studies go "a long way" in showing that many of our fundamental ideas about space appear to be right.