I made each Princess her own unique name so I decided to to the same for their (theoretical) mothers! We see Princess Serenity’s mother (also named Serenity) so I’ve always liked to imagine the other planets each have their own Queen, it’s just that the Moon Queen rules over them all. I also like to imagine that these Queens used to be the first Serenity’s guardians at one point, just like the Inners watch over Princess Serenity. :P
Unlike with the Princesses, I decided to give each Queen a mythological name.
Queen Athena, Ruler of Mercury
Athena isn’t related to Mercury/Hermes, but Sailor Mercury is the Solider of Intelligence and Wisdom and I imagine the inhabitants of Mercury place a high value on both of these. So their Queen is named after the Goddess of Wisdom.
Queen Anat, Ruler of Mars
Anat is an important Semitic war goddess. I have a feeling that all of the Martian queens are named after war deities.
Queen Hippolyta, Ruler of Jupiter
Hippolyta was the Queen of the mythological all-female warrior race, the Amazons. The Amazons were widely known for both their strength and their femininity, just like Makoto. I assume her mother is likely the same (and maybe this is even a trait for all Jovians) so I gave her the name of the Amazon Queen.
Queen Aphrodite, Ruler of Venus
Self-explanatory, Aphrodite is the Greek Equivalent of Venus. Not terribly creative but it suits her well! :P
Queen Proserpina, Ruler of Pluto
Proserpina is the Latin equivalent of Persephone, Queen of the Underworld. Pretty self-explanatory.
Queen Theia, Ruler of Uranus
Theia was a Titaness, goddess of sight and the shining light of the clear blue sky.
Queen Amphitrite, Ruler of Neptune
Amphitrite was the wife of Poseidon (Neptune) in myth and an important sea goddess.
Queen Morana, Ruler of Saturn
Morana is a Slavic goddess associated with seasonal agrarian rites based on the idea of death and rebirth of the nature. She is associated with death and winter and often described as the goddess of death. All of this ties in heavily with Sailor Saturn and her role.