NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2022 Dec 24, 12:13 -0800
K McGraph
You wrote: I'm making a celestial globe and wondering if there is a source of gores based on the standard navigational stars. I can make some from a standard star chart but could be a bit challenging.
That would be an interesting project. If you designed a standard 10-degree gore, you could print off 36. Now then mathematicians; could you draw the sides with large radius compasses, or would you need to construct a ‘true shape of section’ using old fashioned tech drawing? Heaven forbids, you might even try cosine declination, x=1/2cos.dec. The latter might not be a bad idea, because you could leave the declination lines on very faintly, which would aid drawing the stars on your globe.
Post-Christmas, you might find an unwanted Earth globe in a charity shop for a few £s’/$s to stick the gores on. I seem to remember there are vintage globemaking videos on You Tube. I was going to paint my spare globe matt white and guess where to draw the stars, but this might be a better idea.
Now then programming ‘buffs’; there’s a chocolate orange for the first person to produce a programme in ‘Excel’ that will draw a few strips of gore in the fashion I’ve shown below. Sorry if I’ve drawn it inside out; I’m only an air navigator. The radius of globe and the number of gores need to be variable, and there are bonus marks if you toss a few stars in as well. (Ignore where I wrote Aries. I started at SHA=0, Right Ascention=24hours, but then I couldn't find many stars in that area of the sky, so I renumbered the SHA/RA (with difficulty as you'll note).) DaveP
