Distant quasar illuminates a filament of the cosmic web

(University of California - Santa Cruz) Astronomers have discovered a distant quasar illuminating a vast nebula of diffuse gas, revealing for the first time part of the network of filaments thought to connect galaxies in a cosmic web. Using the 10-meter Keck I Telescope at the W. M. Keck Observatory in Hawaii, researchers at University of California at Santa Cruz detected a very large, luminous nebula of gas extending about 2 million light-years across intergalactic space.