A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Peter Hakel
Date: 2021 Nov 14, 10:30 -0800
I remember having this discussion here on NavList several years ago, when I first found myself adding an ad hoc term to the SHA of this star (I think it was +0.4’ the first time, now it is +0.9’), and other NavListers offered explanations (maybe Paul Hirose and/or Antoine Couette - sorry, I don’t have time to dig through the archives right now). Maybe the proper motion of R.K. indeed has a significant nonlinear component. Interestingly enough, though, its declination does not need to be “fixed” like this at this time.
Anyway, perhaps other tools such as yours or Astron will implement a more accurate model for R.K.’s proper motion. I lean toward leaving it in aries_stars.xls as it is as long as it’s still “good enough” for navigation purposes for the upcoming year. Sirius looks OK so far.
From: Frank Reed
Date: 2021 Nov 14, 09:05 -0800