We all saw the historical landing of Rosetta’s Philae on comet 67P/Churyumov-Gerasimenko; we saw the pictures. But how does he sound? Here you can listen to him.
The European Space Agency (ESA) was surprised by the comet’s sound, inaudible for human ears as it has a frequency of 40 to 50 milihertz. What you can hear are vibrations from the magnetic field of the comet, here amplified by factor 10,000. The sound is probably caused by neutrons (particles without electric charge) coming from the comet which acquires negative or positive charge in space (a process called ionization).