More than a kilometer underground, in what used to be a gold mine, inside a tank filled with tons of liquid xenon, “something” struck the nucleus of an atom. The tiny collision left an unusual energy signature that researchers are still unable to explain, but the scientists behind the experiment believe this could be the most convincing physical evidence of dark matter to date.
\n\nDark matter is one of the most important and elusive substances in astrophysics. Though it makes up about 85 percent of the matter in the universe, we can’t observe it directly because it doesn’t interact with light or much else. Most of the evidence for its existence comes from its gravitational effects, the mass of dark matter having tugged on the atoms of the early universe to form stars, galaxies, and the vast web of intergalactic structures visible today.
\n\nBut the enigma of dark matter is complex. Scientists don’t even know what it is made of, whether it’s a single type of particle or an entire set of particles that interact with one another in ways we do not yet understand. The most fantastical explanations even suggest that it consists of black holes. One of the…
Original source: https://www.wired.com/
