Comet 67P 'song' captured by Rosetta spacecraft

The European Space Agency has released this audio of the "song" coming from comet67P/Churyumov-Gerasimenko. The recording was made by the Rosetta spacecraft as it approached the comet.

The ESA says the sound seems to comefrom oscillations in the magnetic field around the comet, but exactly how the noise is being produced remains a mystery.

The "song" has a frequency of40-50 millihertz, which is far below the normal human hearing range of 20 Hz to20 kHz.

The ESA said the frequency had to be raised by a factor of about 100,000 to make it audible to humans.

• Read more about today's Rosetta mission news, including how drilling has begun