This is a podcast Extra from Nature.

And this is the sound scientists have been waiting for,

the sound of gravitational waves being picked up by the LIGO detectors.

Reporters Adam Levy and Alexandra Witsy are in Washington, D.C.,

where yesterday, Thursday, the 11th of February, the LIGO team

announced that they had detected gravitational waves.

Yesterday evening after the press conference was over, Alex and Adam sat down to take stock

of the new findings.

Over to you guys.

So I am here in Washington, D.C. with Alex Wittsey.

Hi, Alex. Hello, Adam.

So we've had quite a busy day. What have we been doing?

We've been listening to the first ever direct detection of gravitational waves.

We're here in the National Press Club, and there was a giant press conference this morning

with all the key members from the LIGO collaboration.

That's that machine, one in Washington State and one in

Louisiana that's been hunting gravitational waves, these ripples and space time, which Einstein

predicted and nobody had found directly until today. Now there've been rumors for some time that LIGO

might have found gravitational waves. What changed today?

Yeah, there have been rumors for some time.

Actually, the detection was made all the way back in September.

And aside from a couple of really excited tweets from some physicists who didn't actually have

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