“This research is a great example of collaboration between telescopes, and creates a new benchmark for how to spot the light coming from the faint filaments of the cosmic web,” adds Norbert Schartel, ESA XMM-Newton Project Scientist.“More fundamentally, it reinforces our standard model of the cosmos and validates decades of simulations: it seems that the ‘missing’ matter may truly be lurking in hard-to-see threads woven across the Universe.”Piecing together an accurate picture of the cosmic web is the domain of . Launched in 2023, is exploring this web’s structure and history. The mission is also digging deep into the nature of – neither of which have ever been observed, despite accounting for a whopping 95% of the Universe – and working with other dark Universe detectives to solve some of the biggest and longest-standing cosmic mysteries. , The filament is made up of hot intergalactic gas (shown in mottled black-yellow), a type of ‘ordinary matter’ that has proven really difficult for astronomers to find. “For the first time, our results closely match what we see in our leading model of the cosmos – something that’s not happened before,” says lead researcher , 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 .