1775: "The Signal Einstein Thought We Might Never Hear"

Interesting Things with JC #1775: "The Signal Einstein Thought We Might Never Hear" – Two LIGO detectors register the same gravitational-wave signal seven milliseconds apart as two black holes merge 1.3 billion light-years away. The signal lasts about two-tenths of a second, while the instruments measure changes smaller than the width of a proton after decades of attempts failed to detect one.