Zhe Ikiyuyu owned a moon that orbited around Ouloumos and was connected with it by a space elevator.
Zhe used the moon as a creative retreat for artists, writers and students. She also hosted parties that the Tenth Doctor remembered with delight.
He brought Gabby Gonzalez to this moon to meet Zhe, by which time Zhe was in stasis for about a hundred years and the moon was under the control of her apprentice. (COMIC: The Arts in Space)