NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Obscure Nautical Almanac star
From: Sean C
Date: 2021 Jan 2, 23:14 -0800
From: Sean C
Date: 2021 Jan 2, 23:14 -0800
Frank,
You wrote:
"Speaking of beta Hydri... Stellarium users, have a look at the data for this star. It looks to me as if the proper motion data is incorrect. It's not really "close" but then again it's "in the same ballpark" as what I believe would be the correct numbers. Any thoughts?"
For β Hyi, Simbad gives a proper motion of +2219.54 mas/yr in R.A. and +324.09 mas/yr in dec.
The FK5 catalogue gives +1003.785µ / +323.7µ.
My experience with making an almanac leads me to believe the FK5 numbers. But ... no matter which numbers you use, that is relatively fast.
I haven't tested it in Stellarium yet. I will post anything relevant I might find. If the numbers Robin quoted are correct, then I believe Stellarium is off.
Regards,
Sean C.
