[Kstars-devel] Star catalogs (was Popup menu usability)

[Khudyakov Alexey]

On Thursday 05 March 2009 16:20:39 Médéric Boquien wrote:
> Le Thursday 05 March 2009 05:44:44 Khudyakov Alexey, vous avez écrit :
> > One thing I dislike in current catalog handling is cheating about
> > spectral class.
>
> It is not cheating. It is inferring from the available data.
>
My point is that such inferring is bad. Maybe cheating is not right word.
It wasn't measured. It's kind of "We think that it's correct", not "We 
measured it (and think that is done correctly)". Moreover Akarsh says that in 
some cases it was guesswork. One cannot rely on such data. B-V itself would 
be more useful. 

> > Tycho2 doesn't provide spectral class information (GSC and USNO
> > too). But in details dialog it has spectral class like 'F?'. Derived from
> > B-V presumably. Not a nice thing to do.
>
> Do you have any better idea? We won't get the spectra of 100 million stars
> anytime soon. Even gaia will provide spectra only for a tiny fraction of
> them. The colour is a relatively good indicator of the spectral type. Far
> from perfect but still the best in our case.
>
In fact yes. Do not provide unavailable data at all. (-: