Although technology has developed massively over the last 20 years, we could never have expected that we would be able to listen to the sound of a black hole. However, the clever boffins at NASA have managed to record it for us, and they've published it in a format humans can hear.
"But wait", you might cry, "how would sound travel in a vacuum? Didn't Alien teach us in space no one can hear you scream?" Luckily the scientists at NASA can explain that to us: "A galaxy cluster has so much gas that we've picked up actual sound. Here it's amplified, and mixed with other data, to hear a black hole,"
The data, and the sound, were recorded by the Chandra X-Ray Observatory, a space telescope launched from the Columbia space shuttle in 1999. The galaxy they've been watching is Perseus which you can see in the northern sky. Although the sound was collected some time ago, NASA released it for Black Hole Week in May.
So how did they make this discovery? Here's what NASA said: "Astronomers discovered that pressure waves sent out by the black hole caused ripples in the cluster's hot gas that could be translated into a note — one that humans cannot hear some 57 octaves below middle C."
The sound is surprisingly sinister, but it's awesome as it gives us a new perception of the universe. It doesn't always have to be that way, though. NASA has captured the "music" of another black hole. This one is at the centre of the Messier Galaxy, which is more than 50 million light-years away. Unlike the black hole in Perseus, this track includes data from Chandra, the Hubble Telescope and ALMA (Atacama Large Millimeter Array) based in Chile.
It's truly remarkable that we have technology that records data from so far away. It's even more amazing that NASA can interpret it in a way that we can all understand. It's unlikely that man will be able to reach these galaxies in our lifetime, but these sounds make these galaxies seem just a little nearer and more familiar.