<p> The program <tt>addstar</tt> may be used to build a DVO-style database from the USNO-B raw catalog, or several other reference catalogs in known formats. In order for <tt>addstar</tt> to find your copy of the USNO-B database, you must set the configuration variable <tt>USNO_B_DIR</tt>. This is found in your <tt>~/.ptolemyrc</tt> file, or you may set it on the command line with the flags <tt>-D USNO_B_DIR (your path)</tt>. The USNO-B data will be loaded into the DVO database defined by your <tt>CATDIR</tt> configuration variable (also in <tt>~/.ptolemyrc</tt>, or override with <tt>-D CATDIR (output)</tt>). The data is actually loaded in two passes: one for blue and one for red. Use the following example commands: </p>

<tt> addstar -D CATDIR catdir.usno.test -D USNO_B_DIR /data/alala.0/elixir/srcdir/refs/usnob -cat USNOB -photcode USNO_RED -region 0 1 0 1</tt>

<tt> addstar -D CATDIR catdir.usno.test -D USNO_B_DIR /data/alala.0/elixir/srcdir/refs/usnob -cat USNOB -photcode USNO_BLUE -region 0 1 0 1</tt>

<p> The <tt>-region</tt> option tells addstar to limit the ingest to the specified region on the sky. The syntax is <tt>-region RAstart RAend DECstart DECend</tt>, where the RA and DEC values are in decimal degrees. The default range is the entire sky, which may take some time (1-2 hours?) to complete.</p>