&gt; <i>And then the ringing stopped as the two holes coalesced into a single black hole, a trapdoor in space with the equivalent mass of 62 suns. All in a fifth of a second, Earth time.</i><p>Am I reading this correctly, that shortly after the detector came online we just happened to observe the exact moment a billion years ago that two black holes collided?<p>Was that extremely coincidental? Or do these events happen all the time, and so if it wasn&#x27;t those two black holes it would be two others?