Star Wars Encyclopedia of Starfighters and Other Vehicles.Aftermath: Empire's End (First appearance, simultaneous with Aftermath: Empire's End audiobook).Aftermath: Life Debt (First mentioned, simultaneous with Aftermath: Life Debt audiobook).In Aftermath: Life Debt, the ship was confirmed to be Sheev Palpatine's command ship.

However, the ship being referred to has since been confirmed to be the Executor. The Eclipse was first mentioned in the junior novelization of Star Wars: Episode VI Return of the Jedi by Tom Angleberger. Sloane intended to board the Eclipse and rebuild the Empire. After Brendol spotted the Eclipse, Sloane ordered the Sentinel piloting the Imperialis to bring the ship in and rejoin with the others. The New Republic defeated the Empire at the Battle of Jakku, and Sloane, together with Commandant Brendol Hux, his son Armitage, and a cadre of child soldiers, boarded the Imperialis and traveled to the Unknown Regions of the galaxy, where they discovered the Eclipse. During the Battle of Jakku, after former Grand Admiral Rae Sloane defeated her former ally, Counselor to the Empire Gallius Rax, she was instructed by Rax before he died to take a replica of the Imperialis, find the Eclipse and reform the Empire. It was believed to have been destroyed by a fleet of New Republic vessels with Ackbar's flagship, Home One, firing the ship-killing shot by the year 5 ABY. At one point during its service, the Eclipse bombarded a celestial body along with three Imperial-class Star Destroyers. In the report, Ackbar mentioned the Eclipse, noting that it was rumored to be the flagship of Emperor Palpatine, which turned out to be accurate. Sometime after the Arrth-Eno Mission undertaken by the Rebel Alliance during the Galactic Civil War, Rebel Alliance Admiral Gial Ackbar wrote a report to Commander-in-Chief Mon Mothma regarding the Executor-class Star Dreadnought. It's time to rejoin with those who came before.' вЂ•Brendol Hux, and Rae Sloane upon seeing the Eclipse

The eclipse super star destroyer