aud allows to look in the database for any type of data
for a list of stars defined either by a selection made previously, or
by the content of a database file, like for example the list of red giants,
or a list of star numbers defined by the user.Like other commands the various actions are performed according to the options and arguments given on the command line.
One can receive either the existing data requested or the list of stars that do not have the requested data depending on the option used.
The various possibilities offered by the command aud are: