Sigma Ceta was one of the eight Satrapies of the Cetagandan Empire. It might also have been called Ola Three (Ola III), or perhaps it connected to a planet or system of that name.
Like the other planets of the Empire, Sigma Ceta was ruled by a satrap and planetary consort. Its former governor, the haut Ilsum Kety, was the mastermind behind a treasonous plot to involve Cetaganda in a war with Barrayar while furthering his own ambitions. He was forcibly retired, and a new governor installed. Its planetary consort was the haut Nadina.
- Cetaganda chapters 7,8,12,13,14