I cannot get the player to stick here, so...https://www.vox.com/science-and-health/2018/1/8/16822272/black-hole-looks-like-what
We can’t see a black hole yet. But we can “hear” them collide.
When two black holes collide, they unleash a massive wave of gravitation.

Just as sound waves disturb the air to make noise, gravitational waves disturb the fabric of spacetime to push and pull matter as if it existed in a funhouse mirror. If a large gravitational wave passed through you, you’d see one of your arms grow longer than the other. If you were wearing a watch on each wrist, you’d see them tick out of sync.

When two black holes collide, they unleash a massive wave of gravitation. But by the time they reach Earth 1.4 billion years later, those waves have become very faint (like how the ripples from a stone dropped in a pond mellow out the further you get from the stone).

But in the past few years, scientists have been able to listen in on these ripples with LIGO and VIRGO, huge, global experiments that can detect these tiny ripples in spacetime.

Because the waves LIGO detect have a frequency that’s comparable to the range of frequencies we can hear, scientists can pump up the volume and translate them into sound. (Yes, this isn’t exactly what it sounds like, but rather an audio representation of the data. And, yes, the event would have made no noise in the vacuum of space.)

 

I must admit that I'm kinda disapointed, I expected something "bigger" ... ^^

Thanks for the link!

 

Me too, it is just a blip of a sound, but as they mention, the gravity wave has been dissipating over a billion years and we are able to pick up but the faintest of signals. It think that it is pretty amazing that scientists can even work it out at all!

 

I fully agree with you, that's really amazing!