Author

Topic: Sun rising angle

John

posted March 22, 2021 02:15 PM
I have been reading Emergency Navigation (2nd edition) and I have a question concerning the Sun rising angle table 61 on page 80
I understand the basics of amplitude and the method of determining it (for any date as described in fig 6.3). So if I’m using a latitude of 50 deg N then Max Amplitude is 38 as per fig 6.5 and then on 11 Nov (say) then the amplitude will be about 26 degs. That is the sun will rise at 26 deg south of east 116 deg from north
If I understand table 61, I enter a latitude of 50 deg (N) at the left and an amplitude of 30 deg along the top and thus get a rising angle of 34 deg Why are there values for rising angle greater than the max amplitude for a particular latitude? That is a rising angle of 24 deg for a amplitude of 50 deg and a lat of 50 deg Is there a formula for calculating the values in table 6.1?
From: UK


John

posted March 22, 2021 02:20 PM
Sorry just realised posted in wrong forum
From: UK


David Burch

posted March 22, 2021 03:06 PM
Thats OK. I will move this to Emergency Nav and we go from there.
From: Starpath, Seattle, WA


