[fitsbits] FITS astrometry formats

[Steve Allen]

On Fri 2004-08-20T18:19:35 +0200, Walter Jaffe hath writ:
> I want to store all this in FITS bintable formats, with the current IAU
> standards (descended from the Jaffe/Cotton document) as a starting point.
> In addition I want to store emphemerides, geodeitic information... that
> has been used in the reduction.

Putting aside the use of pre-existing astronomical nomenclature, which
is certainly a good thing, this sounds like an application where there
could be many different tables with various interrelationships.

We have had good experience using the notions of relational databases
when designing the table formats.  We have applied the normalization
notions found in database texts such as the one by Codd and Date.  In
most cases we have tried to create table schemata which follow the
Third Normal Form.  We find that the normalization is far preferable
to the kinds of empty fields or duplicated fields which tend to occur
in single "flat" table schemata.

Our tables have various primary and foreign key relationships with
each other.  The entire content such FITS files can be ingested
directly into a database or extracted directly from a database by SQL
commands.


--
Steve Allen          UCO/Lick Observatory       Santa Cruz, CA 95064
sla at ucolick.org      Voice: +1 831 459 3046     http://www.ucolick.org/~sla
PGP: 1024/E46978C5   F6 78 D1 10 62 94 8F 2E    49 89 0E FE 26 B4 14 93