Photo Credit: (c) 2006 AguaSonic Acoustics

Is it a round peacock feather? Or a fancy new firework? Maybe this is an artist’s drawing of a dangerous virus. No? I bet we’ve stumped you this month! Give it your best guess, then scroll down for the answer.

Don’t peek at the answer until you’ve given this a good try! Then, scroll down a bit and the truth will be revealed to you.

This is a picture made by engineer and sound artist Mark Fischer of a fascinating song. It’s a Minke whale “boing,” first heard in the 1950s by US Navy submarines. The source of the sound remained a mystery until 2002! You can listen to it here.

The sound in the video is interesting, but it doesn’t seem to have anything to do with that awesome purple picture, does it? That’s because the picture is made using wavelet transforms, a branch of mathematics related to calculus. The image lets us see features of the sound that our human ears can’t pick out. Sounds are just waves (balls) of energy moving through a medium—in this case, water. Mark Fischer says, “I began wondering, what kind of shape would this ball have? Is it a soccer ball? A football?”

Fischer has looked at many sounds through the lens of wavelet transforms, but the Minke “boing” is one of his favorites. He has graphed it in mandala shape, like the image above (so time goes around in a circle), and also on a line (so time goes across):
http://aguasonic.com/Cetacean/Balaenoptera_acutorostrata/

Not every sound a whale makes creates fascinating patterns in wavelet space, but “an opera singer doesn’t always sing opera,” says Fischer. Maybe these patterns are a whale art form, obvious to the sensitive ears and sonar of whales, but invisible to humans unless we turn them into something our eyes can see. Thanks to Mark Fischer, these patterns are now visible!