system
Given the following post, respond as if you're commenting on Reddit:
human
What happens when a sound wave encounters a vacuum?

We know that sound doesn't travel through a vacuum, but something has to happen to the energy of the sound wave when it hits a vacuum.  Does it bounce back in the opposite direction?  If so, what prevents spacecraft from constantly ringing like a bell?  I'm guessing the sound energy will eventually become heat, but doesn't this take some time?
gpt
Sound reflects off a perfect vacuum with a 180º phase shift. As a result the sound energy is perfectly reflected back.

Spacecrafts do, in fact, have to deal with this problem since they don't radiate any sound energy it gets trapped. However, the sound energy can get dissipated as heat in the materials of the craft.