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From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: Sunrise/ sunset times
Message-ID: <C5x7q8.8Kv@zoo.toronto.edu>
Date: Fri, 23 Apr 1993 05:10:52 GMT
References: <1993Apr21.141824.23536@cbis.ece.drexel.edu> <1r6f3a$2ai@news.umbc.edu>
Organization: U of Toronto Zoology
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In article <1r6f3a$2ai@news.umbc.edu> rouben@math9.math.umbc.edu (Rouben Rostamian) writes:
>>Hello. I am looking for a program (or algorithm) that can be used
>>to compute sunrise and sunset times.
>
>Here is a computation I did a long time ago that computes the length
>of the daylight.  You should be able to convert the information here
>to sunrise and sunset times.

Sorry, not so -- the changes in sunrise and sunset times are not
quite synchronized.  For example, neither the earliest sunrise nor the
latest sunset comes on the longest day of the year.

You can derive day length from sunrise and sunset times, but not
vice-versa.