sound in space

[maitri]

is it possible to produce sound in space? if so, how?

[Manticore]

No.

[Lord Antares]

Simply put, sound is just a displacement of particles. When you clap, you send a shockwave of motion through the air and the particles move one another in all directions, and this movement is heard as sound in your ears. The more particles there are, the greater the motion. For example, the speed of sound is more than 4 times as fast in water than it is in air, simply because water is much denser (contains more particles per unit of distance^3) than air.

That being said, space is very rare. There are not enough particles to make a sound. So I guess it depends on whether you ask if it makes a sound to our ears if there is such motion which makes a sound. It would be no to the former, but particle propagation works just as it does in other mediums. It's just that there's too little particles and they are too far apart to make a sound for us.

[Strange]

1 hour ago, Lord Antares said:

It's just that there's too little particles and they are too far apart to make a sound for us.

As I understand it, they are too far apart to even sustain a sound wave. 

[Area54]

Accretion discs?

[Itoero]

5 hours ago, maitri said:

is it possible to produce sound in space? if so, how?

I think it depends on the transmission medium. On earth-like planets you might be able to hear yourself clapping your hands.  

[Strange]

22 minutes ago, Itoero said:

 On earth-like planets you might be able to hear yourself clapping your hands.  

That is not "in space" is it?

[swansont]

You can probably flip this and ask what minimum gas density (or pressure) do you need to transmit sound.

 

[John Cuthber]

Not sure but I suspect  that, if the mean free path is bigger than the wavelength it's not clear how you can have a "wave"

[maitri]

is it possible that a specific range of em waves in space are converted to sound waves suitable for our ears? just like a specific range provides visible light?

[Area54]

How do you envisage this conversion occurring? We can accomplish the feat on Earth with a radio receiver, suitably designed, and loudspeakers, but it is difficult to imagine the chance formation of an equivalent device in space.

[hoola]

If an audio frequency gravity wave from a GW transmitter, or being near a merging black hole (chirp), either of which might jiggle the bones in your ears...in which case space itself is the medium of transmission.

Edited August 27, 2017 by hoola

[swansont]

5 hours ago, hoola said:

If an audio frequency gravity wave from a GW transmitter, or being near a merging black hole (chirp), either of which might jiggle the bones in your ears...in which case space itself is the medium of transmission.

It would "jiggle" the rest of your head, too. 

[hoola]

yes, but since the bones of the ear are vastly more sensitive to this jiggling than anything else in your head, sound should be perceived....kind of a "headbanger" experience, familiar to concert goers. I am thinking that since gwaves are quadrapole in nature, that the perceived sound would be affected, perhaps in a "chorus" like fashion, in guitar effects speak..

Edited August 27, 2017 by hoola

[swansont]

6 hours ago, hoola said:

yes, but since the bones of the ear are vastly more sensitive to this jiggling than anything else in your head, sound should be perceived....kind of a "headbanger" experience, familiar to concert goers. I am thinking that since gwaves are quadrapole in nature, that the perceived sound would be affected, perhaps in a "chorus" like fashion, in guitar effects speak..

That's when air is doing the jiggling. 

[hoola]

 Even if the ear doesn't directly pick up the sound, the air in your spacesuit would, although a high gain hearing aid might be needed. The major medium of transmission would still be space.

Edited August 27, 2017 by hoola

[Airbrush]

Does that mean that a sound will be louder on Venus with it's atmospheric pressure 100x Earth, and softer on Mars with atmospheric density of 0.01x Earth?  Would sound on Venus be 100x100=10,000 times as loud as on Mars?

Edited August 27, 2017 by Airbrush

[hoola]

yes, sound on venus would be implosively loud, and then explosively loud on mars...seriously, I presume that any gravity wave experiments are done in space, since there are no bh's on either planet, and if for no other reason than to rule out atmospheric transmission from the tests of gwave transmitters...the jokey nature of your response indicates that you think that gw tranmissions are nonsensical. We have no complete understanding of the phenomena, or even if it is fundamental. Lately it seems to have a probability boost from the recent talk of gravitation as an emergent phenomena. If it is emergent, that seems we have a better chance of interceding in it's workings...

Edited August 27, 2017 by hoola

[maitri]

On ‎27‎/‎08‎/‎2017 at 11:01 AM, Area54 said:

How do you envisage this conversion occurring? We can accomplish the feat on Earth with a radio receiver, suitably designed, and loudspeakers, but it is difficult to imagine the chance formation of an equivalent device in space.

What about the satellites we send to other planets? in a recent video of the Cassini there was an audio while it showed Saturn's aurora . so it could be possible for the satellite to convert the inaudible waves to sound waves of our range..

[Strange]

1 hour ago, maitri said:

What about the satellites we send to other planets? in a recent video of the Cassini there was an audio while it showed Saturn's aurora . so it could be possible for the satellite to convert the inaudible waves to sound waves of our range..

I would guess that was the radio signals from the aurora - like static on a radio. 

Or it may have just been a sound effect added for dramatic effect. 

[Area54]

7 hours ago, maitri said:

What about the satellites we send to other planets? in a recent video of the Cassini there was an audio while it showed Saturn's aurora . so it could be possible for the satellite to convert the inaudible waves to sound waves of our range..

So, a microphone, radio transmitter, receiver, loudspeaker. Sure. However, it looks like I have misunderstood your original question, which I thought was about producing sound in space, not producing sound back on Earth from em waves generated in space. For that I come back to protoplanetary accretion discs I mentioned earlier, which I suspect will be dense enough, in part, to transmit sound waves.

[Airbrush]

On ‎8‎/‎27‎/‎2017 at 3:32 PM, hoola said:

yes, sound on venus would be implosively loud, and then explosively loud on mars...

Does anyone know how much louder a sound would be on Venus than on Earth?

[Airbrush]

"We are confident of our calculations; we have been rigorous in our use of physics taking into account atmospheres, pressure and fluid dynamics. On Venus, the pitch of your voice would become much deeper. That is because the planet's dense atmosphere means that the vocal cords vibrate more slowly through this 'gassy soup'.

"However, the speed of sound in the atmosphere on Venus is much faster than it is on Earth, and this tricks the way our brain interprets the size of a speaker (presumably an evolutionary trait that allowed our ancestors to work out whether an animal call in the night was something that was small enough to eat or so big as to be dangerous). When we hear a voice from Venus, we think the speaker is small, but with a deep bass voice. On Venus, humans sound like bass Smurfs."

https://io9.gizmodo.com/5898514/what-would-your-voice-sound-like-on-venus

No mention of the human voice sounding louder.  Sounds under water on Earth don't sound much louder than sounds in air, sound just travel faster and farther.

[hoola]

I was joking about the " implosive" sound on venus....(as your head implodes)...or eardrums that explode outwards on mars.... the serious point I was trying to make was that if you were orbiting a merging black hole, the space you reside in would be "fluctuated" by the chirp of the merger and ringdown and you might hear it ( if at a close but safe distance) by the fact that the ears would as any material object be stimulated.

Edited September 8, 2017 by hoola

[Mordred]

If you were close enough for your ears to perceive a GW wave you would not be at a safe distance from a BH merger.