Re: Rays of Sunshine

[Robert Cohen <Robert.Cohen@PO-BOX.ESU.EDU>]

Try <http://ww2010.atmos.uiuc.edu/(Gh)/guides/mtr/opt/air/crp.rxml>.

P.S. You don't say exactly what the problem is.  Is it that the rays
appear to diverge from the sun instead of being parallel?  If so, the
word "crepuscular" in the phenomenon name is a hint - they appear
in the evening (or morning) when the sun is relatively low in the
sky - hence the rays are coming toward you.
____________________________________________________
Robert Cohen; 570-422-3428; www.esu.edu/~bbq
East Stroudsburg University; E. Stroudsburg, PA 18301


> -----Original Message-----
> From: Roger Haar [mailto:haar@PHYSICS.ARIZONA.EDU] 
> Sent: Monday, August 18, 2003 11:20 AM
> To: PHYS-L@lists.nau.edu
> Subject: Rays of Sunshine
>
>
> Hi,
>
>         Here is something for which I have not been able
> to think up a proper explaination.
>
>         On a partly cloudy day, one often sees DIVERGING
> rays of sunshine, something like the Japanese flag
> or the Arizona flag.  I think these rays are
> visible because of scattering in the atmosphere
> and they appear to diverge from the sun.  But for
> most of their path rays of light coming from the
> sun are in outerspace and are scattered very
> little.
>
>         At first thought the solution is that the
> sunlight passes through a hole in a more distant
> cloud and is heavily scattered into a broad range
> of angles.  This scattered light then passes
> through holes in nearer clouds to produce the
> rays.  The problem with this is the rays would
> appear to diverge from the hole in the first cloud
> rather than the sun.
>
>         Any thoughts.
>
> Thanks
> Roger Haar