Numero Uno was a ringed planet located in Galaxy Zelta. It was the homeworld of the Unoites.
History and specifics
The natives had been driven from the planet's surface as a result of toxicity from the rings. As a result, they were forced to end their war which had lasted for centuries. When the USS Enterprise explored the planet, the inhabitants (who had relocated to two satellites orbiting the planet) tricked the Enterprise crew into removing the rings. However, the Enterprise crew then forced them to end their war. (TOS comic: "The Ghost Planet")
Notes
Numero Uno on Italian means Number one.