Lightening Concert History

The name was given because the sound slowly decreases in frequency over about 7 minutes. The sound was detected at 15°S 115°W. It was recorded using an autonomous hydrophone array. The sound has been picked up several times each year since 1997. One of the hypotheses on the origin of the sound is moving ice in Antarctica. Sound spectrograms of friction closely resemble the spectrogram of the Slow Down. This suggests the source of the sound could be a friction phenomenon of ice rubbing over land.