https://scitechdaily.com/first-direct-image-of-the-cosmic-web-reveals-the-universes-hidden-highways/
A cosmic filament, 3 million light-years long, has been directly imaged for the first time -- offering a new glimpse into the hidden framework of the Universe!
Matter in intergalactic space is arranged in a vast network of interconnected filaments, known as the cosmic web. Now, after hundreds of hours of observations, an international team of researchers has captured the sharpest-ever image of one of these cosmic filaments. This filament links two actively forming galaxies and dates back to a time when the Universe was only about 2 billion years old.
The Cosmic Web and Dark Matter
Dark matter, which makes up about 85% of all matter in the Universe, plays a crucial role in shaping cosmic structures. Under gravity's influence, it forms a vast, intricate web of filaments. At the intersections of these filaments, the brightest galaxies take shape. This cosmic web serves as the backbone of the Universe, guiding the flow of gas that fuels star formation in galaxies. Studying how this gas moves and interacts could significantly improve our understanding of how galaxies form and evolve.
However, directly observing this intergalactic gas is extremely difficult. Scientists have mainly detected it indirectly -- by measuring how it absorbs light from distant, bright objects. These observations, though valuable, do not clearly reveal how the gas is distributed. Even hydrogen, the most abundant element in the Universe, emits only a very faint glow, making it nearly impossible for previous-generation telescopes to detect this elusive gas.
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