Part of cosmos' missing matter is found

PARIS, May 6 (UPI) -- The European Space Agency says its orbiting X-ray observatory XMM-Newton has uncovered part of the missing matter in the universe.

Scientists say all matter in the universe is distributed in a cosmic web-like structure. At dense nodes of the cosmic web are clusters of galaxies. Astronomers suspected the low-density gas permeates the filaments of that cosmic web.

An international team of astronomers, using XMM-Newton were observing a pair of galaxy clusters about 2.3 billion light-years from Earth when they saw a bridge of hot gas connecting the clusters.

"The hot gas that we see in this bridge or filament is probably the hottest and densest part of the diffuse gas in the cosmic web, believed to constitute about half the baryonic matter in the universe," said Norbert Werner of the Netherlands Institute for Space Research and leader of the research team.

"This is only the beginning," added Werner. "To understand the distribution of the matter within the cosmic web, we have to … ultimately launch a dedicated space observatory to observe the cosmic web with a much higher sensitivity than possible with current missions."