From waves breaking to wind rushing through tree branches, the world around us produces all kinds of music. Still, few sounds manage to match the otherworldly drone of the Mojave Desert’s sand dunes.
The deep booming sounds made by the dunes in Death Valley and the Mojave Desert have been observed for centuries. But recently, Caltech mechanical engineering professor Melany Hunt and a group of researchers decided to study and record the music of the dunes, to better understand the way sound waves move through the sand.
Their study, published in the journal Physics of Fluid, centers on the “booms and burps” caused by avalanching sand. Futurity explains that, when sand is initially disturbed and begins to move, it produces short bursts of sound at different amplitudes. Eventually, those irregular “burps” transform into a single droning note “that resembles a pure note from a musical instrument.”
In addition to observing the naturally occurring sounds made by the dunes, the researchers also discovered that they could trigger the sounds on their own. Futurity explains, “To their surprise, Hunt and her colleagues also learned that by providing an impulse on the surface of the massive mound of sand—a simple hammer blow on a plate, for example—they could trigger the natural resonance within the dune.”
“We had never before observed this in the literature,” Hunt told Futurity. To hear the strange booms and burps of the pre-dawn dunes for yourself, check out Futurity's article.