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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
How to pre-calculate for negative altitudes?
From: Tony Oz
Date: 2017 Oct 23, 06:13 -0700
From: Tony Oz
Date: 2017 Oct 23, 06:13 -0700
Hello!
The Pol{ [ cos(Lat1) · tan(Lat2) - sin(Lat1) · cos(λ2 - λ1) ] , [sin(λ2 - λ1) ] } formula is now my favourite, thanks to Robin Stuart!
But as Lars Bergman has warned me - this works only for above-the-horizon altitudes.
Which formula gives the negative altitudes as well? I want to re-create the sunrise/sunset table with the proper -0°51' Hc.
Thank you in advance.
Regards,
Tony
