Battle of the Rishi moon

"Get a message to the fleet! We have to warn&mdash;"

- Sergeant O'Niner, to his rookie soldiers

During the Clone Wars, a battle took place at the Rishi moon, the site of the Galactic Republic's outpost known as Rishi Station. The Separatist Alliance infiltrated the outpost and intended to keep Rishi Station's all-clear signal active in order to succeed in a surprise attack on Kamino, home of the Republic's cloning facilities. The Republic clone troopers stationed at Rishi Station were forced to destroy the outpost to deactivate the all-clear signal, warning the Republic of the impending attack fleet and forcing the Separatists to withdraw from the orbit of the moon.

Behind the scenes
According to Pablo Hidalgo's internal chronology, where standard months are named "January" through "December", and standard years counted so that 0 BBY begins in "May 1977", the battle took place on "September 25, 1955", placing the event in the fifth month of 22 BBY.