Athega is the name given to a collection of eleven CR90 corvettes. These vessels were part of the Rebel Alliance Fleet. During the Galactic Civil War, these ships were ambushed near the Athega system. They had a small fighter screen when they were attacked by TIE Avengers, Assault Gunboats, and the Victory-class Star Destroyer called Aggressor.
The space battle portrayed in this mission, and the ships involved, are considered C-canon. However, the results of the battle are determined by the player's choices, making the final outcome uncertain. Without further information considered canon, it's safe to say the battle didn't cause any permanent changes, like the destruction of a ship.