Moon question

The cosmos at our fingertips.
Post Reply
starsurfer
Stellar Cartographer
Posts: 5306
Joined: Thu Mar 15, 2012 7:25 pm

Moon question

Post by starsurfer » Mon Jul 16, 2018 11:54 am

Can you hear sound on the moon?

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18805
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: Moon question

Post by neufer » Mon Jul 16, 2018 12:51 pm

Click to play embedded YouTube video.
starsurfer wrote: Mon Jul 16, 2018 11:54 am
Can you hear sound on the moon?
Through the ground, perhaps, ...very poorly.
Art Neuendorffer

User avatar
Chris Peterson
Abominable Snowman
Posts: 18112
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA
Contact:

Re: Moon question

Post by Chris Peterson » Mon Jul 16, 2018 2:11 pm

starsurfer wrote: Mon Jul 16, 2018 11:54 am Can you hear sound on the moon?
There is a lunar atmosphere, so there are sound waves. Far below the human detection threshold, I'm sure. And I don't recommend removing your helmet to test that!
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com

User avatar
neufer
Vacationer at Tralfamadore
Posts: 18805
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: Moon question

Post by neufer » Mon Jul 16, 2018 3:06 pm

Chris Peterson wrote: Mon Jul 16, 2018 2:11 pm
starsurfer wrote: Mon Jul 16, 2018 11:54 am
Can you hear sound on the moon?
There is a lunar atmosphere, so there are sound waves.
Far below the human detection threshold, I'm sure. And I don't recommend removing your helmet to test that!
Note that the (noble gas: argon/neon/helium) lunar atmospheric pressure is only ~3×10−12 hPa
such that the gas mean free path is approximately equal to the diameter of the Moon itself :!:

Under such circumstances an audio speaker can still generate pulses of gas atoms; however:
  • 1) the pulses will only propagate at the fastest speed of the speaker diaphragm motion,

    2) while the pulse structure will rapidly degrade at roughly the nominal speed of sound
    • (due to random gas particle motion).
Art Neuendorffer

Post Reply