On Mars, the speed of sound depends on its pitch. All sound travels slower through Mars’ air compared with Earth’s. But the higher-pitched clacks of a laser zapping rocks travels slightly faster in ...

That additional information could boost performance of passive sonar and echolocation systems for detecting and tracking adversaries in the ocean, medical imaging devices, seismic surveying systems ...

A research team at City University of Hong Kong (CityU) has discovered a new type of sound wave: the airborne sound wave vibrates transversely and carries both rotation and orbital angular momentum ...