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After supernova explosion sound is created...

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  1. Jun 22, 2015 #1
    After supernova explosion sound is created... so what happens to that sound??
     
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  3. Jun 22, 2015 #2

    Borg

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    Sound has to have a medium to travel through like air or water. There is no medium in space for sound to travel through so there is no sound. I.E. in space, no one can hear you scream.
     
  4. Jun 22, 2015 #3

    marcus

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    You and I owe our existence in part to the shock-waves in the interstellar medium created by supernova explosions.

    They temporarily compress clouds of gas which can trigger star formation.

    In a large star-forming region the explosion of one supernova can start a chain reaction of supernovas. the shock waves compress, several other stars form, some of which are massive enough to eventually go supernova themselves, they in turn make waves in the interstellar gas and plasma...
     
  5. Jun 22, 2015 #4

    marcus

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    Subrata Paul you ask a very good question, what happens to the sound?
    I think the answer is: what usually happens to sound. It travels. And its energy spreads out until it fades into background noise and becomes undetectable.

    An important part of cosmology is calculating the SPEED OF SOUND in space at various times like around year 370,000
    when the CMB originated because the speed of sound helps to determine the size of the acoustic waves that we see frozen in the CMB. the sound waves, called acoustic waves, are shown in density fluctuations which we detect as temperature fluctuations in the CMB.

    How big the frozen sound waves look in the sky (their angular size) helps us know how far away the "surface of last scattering" was at that time in the past, and to deduce how far away it is now.

    The speed of sound can be calculated if one knows the temperature of the medium. I'm not sure but I think dark matter is involved so the dark matter density may enter in. For a cloud of ordinary matter it would depend mostly on the temperature---maybe the mean free path too. Have to look this up.

    Anyway it is an important thing in cosmology, and there are ways cosmologists use to calculate the speed of sound based on known conditions at various times in the past. But basically the answer to your question is "the sound travels and spreads out, and in some conditions it can trigger more star-formation"
     
  6. Jun 22, 2015 #5

    Chronos

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    In a supernova, there is a phenomenon called bow shock, which is a pressure wave carried by matter expelled during the detonation. In that sense it is the 'sound of a supernova in the same way baryonic acoustical oscillations are the sound of the big bang.
     
  7. Jun 23, 2015 #6

    Ken G

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    One key difference is that the supernova ejecta are moving faster than the speed of sound in the interstellar medium for quite a long time after the supernova, so "hearing" a supernova would be a bit like hearing a sonic boom-- you don't hear anything until the shock hits you and rattles you.
     
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