Re: Day's lenght

[Brian Whatcott <betwys@DIRECTVINTERNET.COM>]

For a solid answer and more to this technical question
which was in no way trivial, Peter Smith's post nicely
fitted the bill. May there be many more like it tomorrow,
and all next year long on this superlative list, and some
others like Navigation-L;  Rete, Phys-L, Sextants,
Webhead-L.

Happy New Year
Brian W.

At 01:08 PM 12/31/02, Peter Smith, you wrote:
> Pierre Boucher [mailto:pboucher@LAVOILE.COM] asked:
> > Does anybody know of a formula that would compute for a given
> > latitude and a given date the day's length ie. how many hours
> > from sunrise to sunset?
>
> For a web page that performs the calculation (and whose source you can
> steal code from), see the NOAA page at
> <http://www.srrb.noaa.gov/highlights/sunrise/sunrise.html> .
> It has pointers to other Sun calculators and discussions of the formulae
> and corrections.
>
> Juergen Giesen has a nice explanation of the geometry of the problem at
> <http://www.jgiesen.de/astro/solarday.htm> . The page also points to other
> pages which contain Java applets to perform this and related calculation.
>
> However, this being a group emphasizing traditional methods, you should
> look at <http://www.uwsp.edu/physastr/rislove/astrolabe/suncrss.htm> ,
> which shows how to solve the problem using an astrolabe.
>
>  -- Peter

Brian Whatcott
  Altus OK                      Eureka!