The day before Rosetta’s Philae lander made history by landing on the surface of the comet, ESA released an audio clip of Comet 67P/Churyumov-Gerasimenko singing.
I know what you’re thinking…sound waves can’t travel through space! And you, my friends, are correct. What you hear is not an audio recording, it is a translation of variations in the magnetic field around the comet, due to interactions between 67P/C-G and solar wind. These variations resulted in frequencies between 40 to 50 millihertz, about 10,000 times lower than can be detected by humans. ESA scientists altered the frequency of the comet’s song into human hearing range, and discovered it was a series of clicks that change tone.
“This is exciting because it is completely new to us. We did not expect this and we are still working to understand the physics of what is happening,” RPC principal investigator Karl-Heinz Glaßmeier said on the Rosetta Blog.
Click below to stream the audio recording: