Albert Einstein predicted it in 1916; scientists confirmed it in 2016: Gravitational waves have been detected, an effort backed by "2 detectors, 1,000 scientists, 16 countries, and 25 years," as an introductory video trumpeted at a Thursday morning press conference. "Ladies and gentlemen, we have detected gravitational waves. We did it," said David Reitze, the executive director of the LIGO (Laser Interferometer Gravitational-Wave Observatory) project. He then went into an explainer: "These gravitational waves were produced by two colliding black holes that merged to form a single black hole 1.3 billion years ago" and detected by LIGO on Sept 14, 2015; LIGO's two observatories, in Washington and Louisiana, recorded a signal "nearly simultaneously," said Reitze.
The New York Times reports on what happened in layman's terms: "Conveyed by these gravitational waves, an energy 50 times greater than that of all the stars in the universe put together vibrated a pair of L-shaped antennas" in those observatories. The machinery moved "by 1/1000 of the width of a proton particle. LIGO detected it. Amazing," declares the Guardian. After months of "careful checking, rechecking, analysis ... we've convinced ourselves" of the find, Reitze said. It's a huge accomplishment, but Reitze emphasized that so much of what is exciting about this is where we go from here. "Four hundred years ago, Galileo turned a telescope to the sky and opened the era of modern observational astronomy," he said, adding that today, we, too, open a new scientific era. (Read more gravitational waves stories.)