[Kstars-devel] Wrong epoch in stars data

[Akarsh Simha]

> Sorry to keep pestering about this, but I think the problem is serious.
> 
> Main stars coordinates in kstars are expressed in J1991.25 and not
> J2000, and are interpreted as they were expressed in J2000. You can
> verify this easily with the "calculator" and match the results with HIP
> data (Sirius A: http://vizier.u-strasbg.fr/viz-bin/VizieR-S?HIP%
> 2032349).
> 
> I can provide data in J2000 based on textual stars.dat as provided with
> kstars distribution, but I don't have time and knowledge enough to
> regenerate the db used by the application.
> 
> Please note, ALL data from HIP are in J1991.25 so the position of nearly
> all the main stars kstar is actually wrong.

Hi Massimiliano,

I agree this is a serious problem! So could you tell me if only
Hipparcos is affected, or is the entire USNO NOMAD on J1991.25? If I
remember correctly, we had a separate Erik Hog Tycho-2 catalog, and
Jason did a cross-match against Tycho-2 to separate out Tycho-2 from
NOMAD.

So it's unlikely that only Hipparcos stars are affected. I'd
appreciate if you could shed some more light on the problem. It should
be easy to change the epoch of the catalog.

Regards
Akarsh