G. G,
as John said, Cartgen allows just about any catalog to be generated for
CdC. I suppose if you wanted it badly enough you could start working on
it :-)
I don't think CdC online resources are generally meant for large Vizier
catalogs but I might well be wrong about that. I thought it was aimed at
frequently changing data like asteroids and comets.
Sander
G. G. wrote:
>
>
> While looking at the list of catalogs at Vizier site, I stumbled into
> NOMAD catalog. It looks like the best catalog (currently) for
> astrometric and photometric data. I was wondering if in the future
> version of CDC an access to this catalog can be added in the "Online
> resources".
>
> Also, does anyone know how to download a catalog from Vizier site? I
> looked and looked, but could not figure it out.
>
> By the way here is the description of NOMAD catalog:
>
> Description:
> The Naval Observatory Merged Astrometric Dataset (NOMAD)
> contains astrometric and photometric data for over 1 billion stars
> derived from the Hipparcos (I/239), Tycho-2 (I/259), UCAC2 (I/289),
> and USNO-B1.0 (I/284) catalogs for astrometry and optical hotometry,
> supplemented by 2MASS (II/246) near-infrared photometry. For each
> unique star the "best" astrometric and photometric data are chosen
> from the source catalogs and merged into a single dataset. A sequence
> of priorities is followed and NOMAD contains flags to identify the
> source catalogs and gives cross-reference identifications. This
> first release of NOMAD is not a compiled catalog; that is, if a star
> is identified in more than 1 of the above mentioned catalogs, only
> 1 catalog entry is chosen.
> Thus the local and global systematic errors of the various
> source catalogs will be present in this version of NOMAD. All source
> catalogs astrometric data are on the International Celestial
> Reference System within the limitations of the source catalogs.
>
