Re: Sat track photo

Mon, 27 Sep 1999 00:16:54 -0400

I received these 2 comments:

Jean-François Guay wrote:
> JAY RESPLER wrote:
> > No one answered, can a refractor give diffraction patterns?
> Yes, a refractor produce a diffraction patterns but it will be concentrics circles around
> stars not spikes

 From: Fred Burger <>
>No, a refractor itself will not produce any linear diffraction
>patterns, since there is nothing in the light path except the
>circular entrance aperture. 

They confirm by belief that the refractor that took the photo would not
cause a diffraction pattern. 

Also, aren't the trails going exactly w-e, and n-s?  They are not going
left-right, up-down.  It would be odd for something causing a pattern to be
offset from the vertical of the camera just enough to be aligned exactly
with the equator.

I think it has to be explained how this refractor could have caused a
diffraction pattern that looks like the photo. Otherwise we're back to 
figuring which sats they are.

Jay Respler
   Satellite Tracker * Early Typewriter Collector
           Freehold, New Jersey