[Kstars-devel] Re: Fwd: Fwd: star catalog

[Akarsh Simha]

Hi Noel

> Tycho2 catalogue data is based on observations by the ESA Hipparcos satellite 
> from 1989 to 1993 (Erik H?g article) and proper motions included in the 
> catalogue are derived from these observations and other 143 catalogues. So, 
> the original data are copyright of the ESA Hipparcos mission, not USNO nor 
> NASA, and the 'cooked' data are copyright H?g et al (or their institutions, 
> namely CUO, USNO, ARI and ESO).
> > 
> > AFAIK, we used data from the NASA ADC, whose policies are here:
> > http://web.archive.org/web/20070303235508/http://adc.astro.umd.edu/adc/ques
> > tions_feedback.html#policies1 for Tycho-2 and that's what deepstars.dat was
> > built out of.
> 
> I can not access ADC, but I suposse CDS's Readme is the same since 
> http://cdsweb.u-strasbg.fr/hipparcos.html says ADC is a mirror of CDS. Since 
> there is no relevant info in the Readme, this should imply one of
> a) ADC has no permission to publish Tycho2 as PD
> b) ADC has permission (either explicit or implicit) to publish Tycho2 as PD
> 
> Assuming the second means that at some point, ESA and H?g give their 
> copyrights out.
> > 
> > The Tycho-2 catalog itself was available there, and since it was hosted by
> > the ADC,
> > http://web.archive.org/web/20060908122029/adc.astro.umd.edu/cgi-bin/adc/ca
> > t.pl?/catalogs/1/1259/ the policy must be applicable to Tycho-2 as well.
> 
> True, but read my last sentences

Yes, the terms look flaky. I wonder if they really keep in mind that
astronomy programs might want to use it, and they should have clear
terms and conditions.

Yes, the ADC is now down. But that was, according to Jason, the source
from where he downloaded the files.

If we need further proof, we could write to Cartes du Ciel and
Stellarium. I think both of them use that. And here's Cartes
distributing Tycho-2 data in a downloadable package:
http://www.stargazing.net/astropc/oldversion/download.html

While of course, these are not legal support, if anything, it gives me
more confidence in believing that ADC was not shut down because of
copyright violation or something.


> > So maybe we should say "(c) Erik H??g et al.", but then mention
> > "Public Domain according to <NASA ADC citation>"?
> 
> I think that would be the way, but mentioning ESA too

Yes!

> > When USNO's data was obtained, Jason matched the Tycho-2 stars were
> > matched against the NASA ADC Tycho-2, and got rid of them from the
> > USNO, and sent me the rest of the USNO data for creating the binary
> > files. So for the USNO catalog (USNO-NOMAD-1e8.dat), the mail I just
> > forwarded applies.
> 
> Good news :) but that menas (being scary) that Tycho2 data was used in the 
> compilation of KStars' USNO... better don't think on that

I don't understand the implications. You mean that, in the event that
Tycho-2 is not really public domain, then USNO can't be public domain
either because we used that data to build USNO? But considering that
the data is not included, is that a problem? It's just selective
removal, but none of the Tycho-2 data is in USNO.

> > > That is, should I cite H?g or ESA or just USNO? I must confess I'm a bit
> > > lost, since the Tycho2 name suggests citing H?g and ESA.
> > 
> > I think we should cite H??g and ESA, but mention that it is public
> > domain by NASA ADC citation.
> 
> Agree

Okay!

> So let's do this this way:
> 
> Files: deepstars.dat
> Copyright: 2008 Akarsh Simha <kstars-devel at kde.org>, Jason Harris <kstars-
> devel at kde.org>
> X-Original-Data-Copyright: 2000 E. H?g, C. Fabricius, V.V. Makarov, S. Urban, 
> T. Corbin, G. Wycoff, U. Bastian, P. Schwekendiek, and A. Wicenec
>                            1997 ESA (Hipparcos mission)
> X-Reference: Astron. Astrophys. 355.2, P L19-L22 (2000) :
>              The Tycho-2 Catalogue of the 2.5 Million Brightest Stars.
> X-Original-Data-License: Public Domain (as data has been retrieved by Authors 
> from NASA ADC whose policy is PD, as stated in 
> http://web.archive.org/web/20060908122029/adc.astro.umd.edu/cgi-
> bin/adc/cat.pl?/catalogs/1/1259/)
> License: GPL
> 
> Hope it is true and ok for everybody this way

This looks perfect to me!

Is there someone you know, whom we can consult on this matter, to see
if this is absolutely clear? I could write to developers of Stellarium
and the author of Cartes if required, and see what they have to say
about Tycho-2.

Regards
Akarsh