Do any of the astronomical symbols of non-classical planets have any basis in historical symbols for the deities they are named after? All of them seem to have been assigned in the 19th Century with the exception of Chiron, which hasn't been adopted yet anyway.
Interesting coincidence, the Renaissance magic grimoire, the Goetia, features a symbol exactly like the symbol of Ceres. Scroll down to the "pentagonall figure of Solomon".
