Astronomers used 69 fast radio bursts as cosmic backlights to complete the clearest census yet of the universe’s missing ordinary matter, finding that roughly 76% resides as extremely diffuse ionized gas in the vast spaces between galaxies — while only 9% remains inside galaxies as stars and gas.
The universe’s “missing matter” was never thought to have vanished. Cosmologists could infer how much ordinary, atom-building matter…
