In <199710060134.WAA10077@platon.itacom.com.py>, on 10/05/97 at 09:31 PM, Alberto Smulders said: >Hi everybody !!! >I know this is off-topic, but it's the only list which is alive I see... >Does anybody know where to find an algorithm to calculate sunrise and >sunset data for a given geographical location ? We need it for our >greenhouse automation software. >Thanks !!! >Albert Smulders >InSAD - Encarnacion, Paraguay >insad@itacom.com.py Check out Peter Duffet-Smith's book Practical Astronomy with your Calculator. It has all you need in an easy step by step approach. Unfortunately there are a fair amount of sine/cosines and arctangents involved. Cheers, Micke ----------------------------------------------------------------- mj@isy.liu.se Michael Josefsson, MSEE Linkvping University Join the RC5 contest with your idle CPU cycles!!!! See http://rc5.distributed.net -----------------------------------------------------------------