Can we hear any sound on moon?
Maybe.Unlike light, sound is a matter compression wave and requires a medium to propagate through. In our everyday lives, that’s usually air or water (where the faster speed of sound robs us of our spatial locating sense).A suited astronaut in space or on the moon can only hear sounds loud enough to pass from the source, through the ground or other objects, into the suit, and into the air inside and/or his or her body. Of course, spacesuits are noisy, so unless that sound is a freight train or a cannon going off, probably, “no.” But in an enclosed, pressurized cabin, and astronaut will hear normally, just like on Earth.On Mars, the the atmosphere is only a fraction of one percent as dense as on Earth—about the same pressure we would feel at 120,000 feet here, those it’s mostly CO2, so it’s denser than it would otherwise be.Martian air pressure is generally too low to prevent water from boiling even at very low temperature, but sound can still travel through the air. An astronaut might not notice, however. Sounds would fade quickly and appear to come from further away, and a suited astronaut, used to hearing only the suit and its mechanisms and motions, would probably be slightly startled by the occasional intrusion of outside sounds, as might happen for example when striking a rock with a rock hammer or bumping into someone playing disco music dangerously loud inside her suit.If you like space, you might like my free award-winning scifi sampler.