[vsnet-id 732] (fwd) Re: [AAVSO-DIS] WW HYA

[Taichi Kato <tkato@kusastro.kyoto-u.ac.jp>]

(fwd) Re: [AAVSO-DIS] WW HYA

Date: Mon, 27 Jan 2003 21:27:11 -0700 (MST)
From: Brian Skiff <Brian.Skiff@lowell.edu>
Subject: Re: [vsnet-id 731] Re: [AAVSO-DIS] WW HYA

     One  of the problems with your listings is that nowhere do you actually
say which of the many coordinates you show for an object is the preferred
one.  Also, you seem to using either old catalogues, or possibly the
coordinates seem to be foro _B2000_, not J2000:

>>  GSC4869.534 085746.29 -031654.2 (2000.0) 13.31 0

GSC v1.1:       085746.39 -031654.6
GSC v1.2:       085746.39 -031654.6
GSC-ACT:        085746.38 -031654.3

>>  USNO0825.06674467 085746.308 -031654.31 (2000.0)  8.6 11.3

USNO-A1.0:            085746.309 -031654.31
USNO-A2.0:            085746.341 -031653.98
GSC-2.2:              085746.386 -031654.25
USNO-B1.0:            085746.383 -031654.33

...so it looks as though you are using some 'unknown' version of the GSC
(the original GSC v1.0?), and persist in using USNO-A1.0 even though it has
been superceded _twice_, and possesses substantial systematic errors in
the coordinates inherited from the GSC v1.1.
     Probably the current 'best' position for this star is from the last
Carlsberg meridian circle catalogue, although the differences with GSC-ACT
(probably second best), GSC-2.2, and USNO-B1.0 are small:

CMC 11     8 57 46.37  -03 16 54.4
GSC-ACT    8 57 46.38  -03 16 54.3
GSC-2.2    8 57 46.39  -03 16 54.3
USNO-B1.0  8 57 46.38  -03 16 54.3


\Brian

VSNET Home Page

Return to Daisaku Nogami

---

vsnet-adm@kusastro.kyoto-u.ac.jp