Scientists have found «missing» half of the matter of the Universe

An international team of astronomers says it has probably found «the missing» half of the Universe’s baryonic matter.

This issue has been of concern to the scientific community for many years. It is believed that the share of ordinary matter is about 15% of the total mass of the Universe. However, in their attempts to quantify it, scientists could not find about half of the of this matter among stars, galaxies, and other space objects.

A team of astronomers has discovered that the diffuse hydrogen gas that surrounds most galaxies is much more abundant than thought. Scientists claim that this gas is so widespread that it may make up the rest of the ordinary matter of the Universe.

As part of the study, astronomers used a spectroscope dark energy (DESI) at the Kitt Peak National Observatory in Arizona, as well as data obtained by the Atacama Telescope in Chile. Observations with DESI allowed astronomers to compile images of about 7 million galaxies to measure the faint effects of ionized hydrogen gas halos at the edges of galaxies. These halos are too faint to be detected using conventional methods.

Instead, the scientists measured how much the gas obscured, or vice versa, brightened the relic radiation. Astronomers found that clouds of ionized hydrogen created almost invisible threads between galaxies. If they span most of the galaxies in the Universe, this could explain the previously undiscovered the rest of the ordinary matter. 

This discovery may also affect current theories about the activity of black holes. Supermassive black holes at the center of most galaxies were thought to eject gas jets only in the early stages of their evolution. However, the discovery of large clouds of diffuse hydrogen gas may indicate that they can fuel black hole activity.

Song of ice and fire in reality: physicists discover a new quantum state of matter

The results of the study are published on the preprint server arXiv

Source: LiveScience