NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2022 Feb 16, 08:56 -0800
Pär Leijonhufvud
You talked of keeping records. This is what the medieval monks did for the stars, but they had to get up several times in the night anyway, and there was less light pollution. I think the Moon’s horns might be a harder problem from temperate latitudes. There are only so many nights per month you could use, even if the sky wasn’t obscured. I think the results might be all over the place, because at first sight, there are so many variables. The attached drawing using a Wikipedia diagram as a base shows them. The word ‘lunatic’ wasn’t dreamt up for nothing.
I think if I was starting a set of ‘star pointer’ observations, I’d start with where the line through Orion’s Sword crossed my southern horizon. There would be fewer variables to explain away and a significant difference between two observers’ latitudes might be used to advantage.
However, if you wished to remain with the Moon’s Horns, a useful experiment might be to first compare outdoor readings with ones from ‘Stellarium’. Then having proved the picture of the Moon on Stellarium was reliable, you could use Stellarium to test the entire range of possible hour angles and ages of the Moon vs time of year, and latitude.
Re time: did you hear about the traveller who was crossing a field of cows when he came upon an old farmer. “Excuse me, but please can you tell me what time it is?”, asked the traveller. The old farmer walked over to the nearest cow, lifted its tail, and after a moment’s hesitation said, “Half past four”. “That’s marvellous” said the traveller “How on earth did you manage that? Well, said the old farmer “Over yonder is t’church clock”. DaveP