Star Catalog

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The FreeFlyer Star Catalog (ffstars.dat, ffstars_high.dat) is a file format native to FreeFlyer that can be used for specifying star data. FreeFlyer provides two star catalog files that you can choose from. The built-in star catalogs were generated using the Yale Bright Star Catalog, 5th Revised Edition. The default star catalog, ffstars.dat, contains the 5080 brightest stars, and ffstars_high.dat contains the 9096 brightest stars.


You can access the attributes of the built-in stars using the global Stars object. You can also specify your own star catalog file to use with FreeFlyer. See the Stars Guide for more information.



A FreeFlyer Star Catalog contains one data record for each star. Each data record contains the star’s ID, its name, its MJ2000 Earth Equator unit position vector, its visual magnitude and its color.



An example of a FreeFlyer Star Catalog containing 3 stars is shown below:


0, Sirius, -0.188802505, 0.94597451, -0.263601630, -1.4, 16777215

1, Canopus, -0.065218447, 0.62177455, -0.780476106, -0.7, 13434879

2, Rigil, -0.393229544, -0.32878623, -0.858644358, 0.0, 11796479


The star with ID = 0 is named Sirius, has a unit position vector of (-0.188, 0.945, -0.263), a visual magnitude of –1.4, and a color whose base 10 representation 16777215. See the Color Reference for more information.