If sound can’t travel in space, where does the energy go?


I understand that there’s no medium in space for the waves to travel through, but what happens to the energy?

In: Physics

Sound comes from vibrations. When something vibrates, it in turn “pushes” into whatever is next to it, what we call the medium. If there is no medium, there is nothing to push against, and whatever vibration is happening would just die down on its own as normal due to its own mass of whatever is vibrating. The energy that would normally be dissipated would just go into letting the source of the “sound” vibrate longer, although the difference is probably very small to notice without specialized equipment.

Ultimately, the vibrations wind up as heat inside the spacecraft. Which then radiates away … at the speed at which a thermos bottle loses heat.