Special columns of identifiers and celestial coordinates

The TST format has the following additional rules for special columns containing identifiers and celestial coordinates.

1. By default, the first three columns in the table are: an identifier (that is, an object name), Right Ascension and Declination. These columns are usually called Id, ra and dec respectively.

2. If the first three columns of the table are not an identifier, Right Ascension and Declination then the TST should contain the following three parameters:

   id_col
   ra_col
   dec_col

   The value of each parameter should be the number of the appropriate column or, if there is no such column, -1. The column number is the sequence number of the column in the list of column names, starting counting at zero.

3. The Right Ascension and the Declination are either both in decimal degrees or the Right Ascension is in sexagesimal hours and the Declination is in sexagesimal degrees. If sexagesimal notation is used then a colon (`:') is used as the sexagesimal separator.

4. The equinox and epoch are specified using parameters equinox and epoch respectively. The default value if the equinox and epoch are not specified is J2000.0.