Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Observing light from distance

  1. Feb 21, 2009 #1
    Which visible light frequency i.e red, yellow , green etc can be seen from greatest distance? and why?
     
  2. jcsd
  3. Feb 21, 2009 #2

    Danger

    User Avatar
    Gold Member

    Welcome to PF, U2_wa.
    The answer to your question is primarily dependent upon who or what is doing the observing. Different sensors have different ranges of sensitivity to various frequencies.
     
  4. Feb 21, 2009 #3
    Yellow. I believe that's the human eyes' most sensitivity to "color"
     
  5. Feb 21, 2009 #4

    Nabeshin

    User Avatar
    Science Advisor

    Human eye sensitivity is actually peaked in the green, ~550nm.
     
  6. Feb 22, 2009 #5
    Thanks. I learn something new each day, especially here at PF!
     
  7. Jan 3, 2012 #6
    Some people perceive 550 nm as a greenish yellow/yellowish green.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook