The Unicode website, surprisingly enough, is the place to look for
information on what's in Unicode. On the very front page of
http://www.unicode.org there is a link labelled "where is my character"
which takes you to a bunch of charts, or to an alphabetical list. Two
clicks later, I have printed out a chart showing all the astrological
symbols available in Unicode range 2600 - 26FF "Miscellaneous symbols"

Answers to the other questions raised are, of course, currently being
discussed by (inter alia) the TEI Work Group on character encoding
issues, whose working drafts are available at
http://www.tei-c.org.uk/Activities/CE/





On Thu, 2003-06-05 at 21:16, Julia Flanders wrote:
> We are encoding a text that contains pharmacological and astrological
> characters (e.g. the signs for Venus, Earth, Mercury; the Rx sign;
> others that I don't recognize).
>
> 1. Does anyone know if these are covered by any ISO entity set? if
> so, which one and where can I find it?
> 2. Does anyone know if these are included in Unicode? if so, which set?
> 3. If neither of the above, does anyone know of an existing set of
> home-made entities that are already in use so we can avoid
> reinventing them?
>
> Many thanks for your help--
>
> Julia
>