what sorts of sounds do dark matter make

Question: what sorts of sounds do dark matter make
- Keywords:
  dark matter,
  gravity,
  sound,
  space
Asked by to Roberto on 13 Jun 2014. This question was also asked by .
- Roberto Trotta answered on 13 Jun 2014:
  
  Dark matter is invisible and silent, so it doesn’t really give out sounds. Besides, space is (almost) empty, so sound waves do not travel in space (that’s why most Sci-Fi movies are wrong: when you hear the spaceship swish by!)
  
  But we can look at the way galaxies are distributed in the Universe, and this also tells us something about how the (invisible) dark matter is distributed. It turns out that the distribution of galaxies (and of dark matter) has got the “shape” of sound waves imprinted on it, coming from the very early Universe (when the Universe was very small and a hot plasma, and sounds could propagate through it, differently from today).
  
  So if we could hear the Dark Matter sound, ie the sound associated with the waves imprinted on the dark matter in the sky, it would be a veeeeery low bassoon tone! Its wavelength is about 300 million light years long! (the deepest sound you can actually hear has a wavelength of just 10 meters or so)

Question: what sorts of sounds do dark matter make