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Time delay of speech to travel from moon to earth

  1. Mar 12, 2009 #1
    So if I'm on the moon is there a delay with the communication to earth?

    What is the speed of sound over satellites verses copper wires?

    Anyone know?, this has been on my mind.

  2. jcsd
  3. Mar 13, 2009 #2
    k what ever u are communicating on will travel at the speed of light
    so it will take about 2.56 seconds for that signal to reach earth.
  4. Mar 13, 2009 #3
    Sound needs matter to travel through. Since the Moon and Earth are separated by the vacuum of space no sound can travel. Hence the saying "in space no one can here you scream". Any communications from Earth to the Moon will be done by sending a electromagnetic signal representing the data (radio, microwave, etc), which travel at the speed of light. Wikipedia tells me that "The average distance from the Earth to the Moon is about 1.282 light-seconds."
  5. Mar 13, 2009 #4
    is the vacuum of space really a vacuum or is it the higgs field.
  6. Mar 2, 2011 #5
    The proper saying is, "In space, no one can hear you scream unless it is the battle cry of a United States Marine Corps Space Aviator!" - R. Lee Ermey, from Space: Above and Beyond.
  7. Mar 2, 2011 #6


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    A Vacuum is defined as an absence of matter. Higgs field has nothing to do with it. And while space is NOT a perfect vacuum, it is about as perfect as you can get. The density of matter in space varies depending on how close you are to stars, planets, nebulas, ETC. Inter galactic space (Space between galaxies) is supposedly the best vacuum possible I believe.
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