Astronomers believe that at least 80 percent of the matter in the universe is utterly invisible. Such "dark matter" presumably seeded the formation of galaxies and keeps them clustered together, yet its elusive qualities have long thwarted scientific investigation. Recent reports are beginning to demystify the unseen components of the cosmos.
Giant filaments of gas (gray) pull together under the influence of dark matter in this computer model. Galaxies (dots) form in the densest regions.Photographs courtesy of Benson, Frenk, Baugh, Cole, and Lacey/Caltech
Astronomer Andy Taylor at the Royal Observatory Edinburgh in Scotland studied how the gravitational pull of dark matter bends light from bright galaxies behind it. In this way he was able to trace the dark component around Abell 901/2, a supercluster of 100 galaxies. The results show that the galaxies are bunched within huge clumps of dark matter, which in turn are connected by long, dark filaments.
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