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Unfortunately, LIGO encountered the 1/1,000,000 almost as soon as it was powered on and they've been waiting for another one like it. Probabilities are funny things ...

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I don’t understand this comment... It’s true that the first event occurred after only two days but ligo have 11 events over two running periods at this point.

https://en.m.wikipedia.org/wiki/List_of_gravitational_wave_o...

I was under the impression from an interview that the first event that LIGO caught was held up so long before release because it was such a stupidly rare occurrence.

Even as there are eleven observed events so far, that is from 2 trillion galaxies in the observable universe [1]. So at 100 billion stars per galaxy [2] a guesstimate is that we are talking about 200 billion trillion stars. Seems even divided by eleven it seems pretty rare. (Not sure if the detector can “see” all those stars though.)

[1] https://en.m.wikipedia.org/wiki/Observable_universe

[2] https://www.livescience.com/56634-how-many-stars-are-in-the-...

What does 1/1000000 even mean? One every million seconds, every million minutes, every million years?

It means "outcome with low prior probability". Just that and nothing more. Seriously.

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