Moon question

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starsurfer
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Moon question

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

Can you hear sound on the moon?

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neufer
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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

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Chris Peterson
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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

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Cloudbait Observatory
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neufer
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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