NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Testing sextant arc error
From: David Pike
Date: 2017 Jan 17, 06:07 -0800
From: David Pike
Date: 2017 Jan 17, 06:07 -0800
I’ve been thinking how one might calibrate the arc of a DIY sextant while living inland without specialised equipment. Is there anywhere on the www a list of the angular difference on the celestial sphere between the 57 navigational stars, or would you have to start off with up-to-date SHA and declination and do the spherical trig? Not my favourite cup of tea. I am aware that you would have to choose your stars to minimise differences in refraction.
Another possible solution would be to compare horizontal angles of ground features with those measured with a real sextant of known good quality, but the features would need to be quite a way away for repeatability. DaveP
