If you've never heard a sand dune rumble, listen up. Marco Polo in the 13 th Century said the singing sands -- which he ascribed to evil desert spirits -- "at times fill the air with the sounds of all ...

"And it's a sound that's very similar to kind of the tones you'd get on a cello." Melany Hunt, a mechanical engineer at Caltech. The dunes sing when sand avalanches down the side, "which would then be ...

In a few places on Earth, sand "sings" as it falls down dunes, making a low droning sound that lies within the bottom half of a cello's musical range. For centuries the eerie humming in deserts ...

A long time ago, some time around the 13th century, as Venetian merchant and explorer Marco Polo crossed the Gobi Desert, he thought he heard the voices of restless spirits. Polo has been recorded as ...