Hi Patrick,
you plan to provide hosting space for these huge files? That's very
generous :) I asked for the UCAC3 catalog so I could write a conversion
program and catgen file for CdC. Clearly if you're already planning to
do that I can just sit back :)
I think the various options you're suggesting are great. I hope you'll
make available the tools needed to splice our own catalogs based on the
DVDs. I suspect the data will be shared at various clubs.
I trust the USNO is a mature organization that can throttle the number
of discs it sends out or put usage restrictions on what people can ask
them for. I said I planned to integrate the catalog into CdC but it's
quite possible they didn't even read that, who knows. Besides, my tax
dollars help pay for it all so I don't feel bad that I received a disk
:) And neither do I feel bad if they send out a few hundred disks to
other interested parties around the world. This is an excellent use of a
few DOD (department of defense) budget dollars. The more this catalog
spreads, the better.
Thanks,
Sander
Patrick Chevalley wrote:
>
>
> Hi,
>
> Yes, UCAC3 is available now but I suggest you not rush to ask a DVD,
> the USNO as probably better thing to do than sending DVD to every
> amateur astronomer on earth.
>
> I not want to add direct access to this DVD from CdC for the many
> reason invoked when I choice to use Catgen for any future catalog in
> CdC V3.
> But I plan to make smaller downloadable version for use with CdC. This
> will be probably more useful for most people here.
>
> This catalog is big, 100 millions stars, it is probably the most
> useful ever produced for the amateur astronomer, so its use on CdC
> need to be carefully planned.
> I want to ask your opinion before to start and provide some small test
> file to be sure all work fine before to upload the big chunks.
>
> Use this tread to discuss about what you want to be include in this
> catalog or what you not want to save space.
> We can also use other tread for specific issues, I start two after
> this message about stars identifiers and photometry.
>
> You can get all the information about the catalog content on this
> page, please read carefully:
> http://ad.usno.navy.mil/ucac/readme_u3.html
> <http://ad.usno.navy.mil/ucac/readme_u3.html>
>
> My first idea is to produce two version, one the most compact as
> possible to produce nice field map. The other more complete with
> identifier and search index but also a bigger download.
> Remember that each character of information we add increase the
> download of 100 MB!
>
> UCAC3 compact :
>
> Include fields:
> RA, DEC, pmRA, pmDEC, Mag : 1.5 GB
> or
> RA, DEC, pmRA, pmDEC, Mag, B-V : 1.7 GB
>
> So it can be tree files of about 500 MB each with South, Equator and
> North downloadable and installable separately.
>
> UCAC3 with ID , index and maybe other need informations :
>
> Include fields:
> ID, RA, DEC, pmRA, pmDEC, Mag, B-V : 2.6 GB
> +
> 100 MB / char, 400 MB / numeric value,
> +
> index size is nbrec * (8 + keylength) : 1.7 GB
>
> Except the index the download can be split in 500 MB to 1 GB parts.
>
> Any idea on this ?
>
> Patrick
>
>
