XPost: sci.physics, sci.physics.electromag   
   From: gah@ugcs.caltech.edu   
      
   In sci.physics.electromag Skywise  wrote:   
      
   (snip, I wrote)   
   >> I believe that 'appears' is important above. How bright something   
   >> appears depends in some sense on the average over the whole   
   >> field of view, and some on the peak. Even more, it could depend   
   >> on which part of the eye it was on.   
      
   > I am reminded of a question that helps put some perspective on   
   > the concept of albedo in astronomy.   
      
   > Which is brighter? A black cat under the sun during the day? Or   
   > a sheet of white copy paper under the full moon at night?   
      
   Also, as was only discovered recently (in astronomy terms,   
   or about 10 years ago), a full moon is brighter than one would   
   expect from a non-full moon. That is, it reflects more back in   
   the direction of the sun.   
      
   -- glen   
      
   --- SoupGate-Win32 v1.05   
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