6 ms·

Whistler (Radio)

• bondarchuk 6y ago
  Just found this yt channel which has audio of whistlers from various space missions: https://www.youtube.com/user/VoyagerPWS/ https://www.youtube.com/user/VoyagerPWS/
• dvh 6y ago
  So this is 1kHz radio wave (300km wave length), I didn't know they can get that low, what is theoretical limit? One of my favorite explanation of how the now-debunked em-drive supposed to work was that it produces radio waves with such a long wavelengths that it doesn't fit observable universe and that makes it push in one direction.
  • 6581 6y ago
    > So this is 1kHz radio wave (300km wave length), I didn't know they can get that low, what is theoretical limit? The theoretical limit is the size of the universe. For practical purposes, this is about the lowest: https://en.m.wikipedia.org/wiki/Extremely_low_frequency https://en.m.wikipedia.org/wiki/Extremely_low_frequency
    • hn3333 6y ago
      Interesting, clicked a bit further and found out that submarines use VLF communication, however it's one way only: "Submarines carry only a VLF reception aerial and do not respond on such low frequencies, so a ground-to-submarine VLF broadcast is always a one-way broadcast, originating on the ground and received aboard the boat." https://en.m.wikipedia.org/wiki/Communication_with_submarines https://en.m.wikipedia.org/wiki/Communication_with_submarine...
      • PoachedSausage 6y ago
        Have a look at the photos of the Rugby VLF Transmitter to see why it is not practical to put one on a sub: https://www.subbrit.org.uk/sites/rugby-radio/ https://www.subbrit.org.uk/sites/rugby-radio/
  • oh_sigh 6y ago
    How would the wave know how big the observable universe is?
• timthorn 6y ago
  The British Antarctic Survey has collaborated with a musician to create a work incorporating these and other Sounds of Space: https://www.bas.ac.uk/project/sounds-of-space/ https://www.bas.ac.uk/project/sounds-of-space/