The Sailor Quartet, also known as the Asteroid Senshi, appeared only in the manga and musicals. They were four Sailor Senshi who were to awaken as Chibiusa's bodyguards when she took on the role of Sailor Chibi Moon.
They are named after four asteroids in the Solar System. Their names were Sailor Ceres, Sailor Pallas, Sailor Juno, and Sailor Vesta. They slept in Amazon stones until they were prematurely released by Queen Nehellenia of the Dead Moon Circus. She corrupted them and turned them into the Amazoness Quartet: VesVes, PallaPalla, JunJun, and CereCere. When they started regaining their memories, Zirconia sealed them back into the stones. After Nehellenia was defeated, Neo-Queen Serenity, at Sailor Saturn's request, healed the stones, freeing the Quartet who were revealed to be Sailor Senshi.
During the Stars Arc, Sailor Chibi Moon, along with her four Asteroid Senshi went back to the past to fight. When Sailor Moon jumped into the Galaxy Cauldron, Sailor Cosmos returned the Sailor Quartet to slumber to be awakened in their proper time in the 30th Century.
- The Sailor Quartet are led by Sailor Ceres.
- The Amazoness Quartet appeared in the fourth season of the first anime but they weren’t revealed to be Sailor Senshi.