Celestia's Cross Reference Catalogs

Celestia comes with several binary cross reference catalogs which provide the corresponding IDs of stars in several popular star catalogs. The locations of these files are specified in Celestia's configuration file, celestia.cfg.

• "data/hdindex.dat" provides HD (Henry Draper) catalog numbers

• "data/saoxindex.dat" provides SAO (Smithsonian Astronomical Observatory) catalog numbers

• "data/gliesexindex.dat" provides Gliese (Gliese Catalog of Nearby Stars) catalog numbers

With an understanding of their formats, you can replace or extend these catalogs.

Format

All numbers are stored in little-endian format. The format is as follows:

8-byte character string   "CELINDEX"
2-byte unsigned integer   version number = 0x0100

Followed by records of length 8 bytes of the form:

4-byte unsigned integer   Hipparcos catalog number (=0 for Sol)
4-byte unsigned integer   Cross reference number