sunset and sunrise time

[Namba Takaya <takayanamba7@xxxxxxxxxxx>]

Dir Sir

Are there any ways to know theoretical sunset and sunrise
time of any location and orbit of the sun also? 

It must be silly question. However,
I have been traveling and I realized the much difference
of lighting time as the latitudes are different. So I wish
to know how different there are among locations which must
be important for the difference of marine productivity in
latitude.

Best Regards,

Takaya Namba
 

Best Regards

Takaya Namba

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