https://www.esa.int/Science_Exploration/Space_Science/XMM-Newton/The_models_were_right_astronomers_find_missing_matter
>“The models were right”: astronomers find ‘missing’ matter
>Astronomers have discovered a huge filament of hot gas bridging four galaxy clusters. At 10 times as massive as our galaxy, the thread could contain some of the Universe’s ‘missing’ matter, addressing a decades-long mystery.
>The astronomers used the European Space Agency’s XMM-Newton and JAXA’s Suzaku X-ray space telescopes to make the discovery.