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Acoustics of Space?

  1. Jul 2, 2011 #1
    The other night I was laying in bed thinking about how we might contact another civilization or at least listen in on one. I then began thinking about the acoustics of space- which I know nothing about. I went to school for audio production so am familiar with acoustics in general but am curious to how they work in space with different types of waves.

    Does gravity have an effect on waves as they travel through space?

    If so would it be possible to anticipate orbits/positions of objects in space in order to bend waves in a particular direction?

    I know that with acoustics here on earth design is everything, if a room is poorly designed there will be poor sound quality and in some instances no sound at all even with very loud music playing-- does this work the same way in space?

    Is it possible that there are many signals floating around that we just don't see/hear because of where we're positioned?

    I would assume that the acoustics of a solar system, galactic plane, and galaxy would all work quite differently... can anyone elaborate on this thought?

    What do you think the best way to effectively communicate with another civilization would be? I would think it best to daisy chain satellites from earth to the edge of our solar system and beyond if possible to ensure we're picking up everything there is.

    Please give me some feedback, all science and opinion is welcome!
  2. jcsd
  3. Jul 2, 2011 #2
    To answer your first question, gravity bends electromagnetic waves as they travel through space. Although EM waves travel in straight paths through space, gravity is essentially the bending of space-time, so the path of the wave is bent as well.
  4. Jul 2, 2011 #3


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    There is no "acoustics" in the vacuum of space. Acoustics is all about sound waves in air. No air, no acoustics.
  5. Jul 2, 2011 #4
    Uh, there are density waves-- Shock waves in gas clouds, even the spiral arms of galaxies.

    Snag is these are at such low pressures and long wavelengths that their hypothetical data rate would make Boomers' ELF look like my home network's Cat-6 cabling...
  6. Jul 2, 2011 #5
    I had a similar thought considered whether or not free electrons, or zero-point vacuum energy would respond to resonance as electrons have an odd-wave like behavior. It was an interesting thought but one I doubt to be acceptable.
  7. Jul 3, 2011 #6

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    In the sense that stever19 was using the term "acoustics" this is true. In the sense that physicists use the term, it is false. Space is not a pure vacuum. The interstellar medium does support sound waves and shock waves, just not wavelengths or frequencies that the lay person would think of as sound. The shock waves in particular are currently believed to be a critical aspect of the star formation process.
  8. Jul 3, 2011 #7
    I think my analogy to music in a room got everyone to thinking about sound waves.

    I really mean any type of wave. Light Waves, Radio Waves, Etc. I know we could never hear in space as we do on earth and I am aware waves would move much differently that we experience them to move here on earth.

    So what about other types of waves... will gravity have an effect on those? I know nothing escapes a black hole, even light- theoretically. BUT... What if a light wave comes within a certain distance of a black hole OR any super massive object--- could that objects gravity bend the light in another direction--- or bend the "wave" in another direction? so I.E. We on earth would, if not for a black hole, would see the light from a star but because of the positioning the black hole's gravity bends the light in another direction so we on earth never see it? -- is this possible? if not with light with any other type of wave?
  9. Jul 3, 2011 #8


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    Yes, the curvature of spaces causes them their path to curve and also to gain or lose energy (change frequency/wavelength) depending on the path between the emitting source and the receiving source. Going up from a gravity well reduces the energy and increases the wavelength, while going down into a gravity well does the opposite.

    Yes as long as you know the full effects of gravity for between you and the receiver. For example, I could send a signal to someone opposite of me around a black hole by sending it in a precise direction and using the black hole to bend the signal around to the receiver.

    Kind of. It's more of what's between you and the receiver. You can't send a visual wavelength laser through a large dust cloud, but you can send a radio signal through. It's really about the integrity of the signal upon receipt. Kind of like when you start getting out of range of a radio station. You can still hear it at first, but the signal degrades and the quality worsens until its nothing but static.

    Absolutely. A radio signal sent from say an alien planet could be missed by us because of interference, signal blockage, we aren't in the right direction, etc.

    I don't really know what you mean by this.

    If you want to talk about ONLY the quality of the communication, sure. However the expense required would be much much greater than simply sending radio signals through space which would have nearly the same, if not the same effect.

    Light only falls into a black hole if it passes through the Event Horizon. This isn't some special physical boundary, but merely the point furthest away from the BH that light cannot escape the gravitational pull. To make a crude analogy, a spaceship flying at 10% the speed of light would have a much larger "Event Horizon" for itself and would fall into the BH from a much greater distance than light would.

    Because of the way black holes affect light, they don't "block" most things. The light that would have been travelling in a different direction and not towards us is bent by the BH and is eventually picked up by us. Look up Gravitational Lensing for this effect.
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