The Oktos Nebula was an extensive, intensely radioactive cloud composed of gas, enveloping the planet of Ganath and effectively isolating it from the broader galaxy. Its outermost extensions reached the borders of the Y'Toub system. The Oktos Route followed a course that avoided the main body of the nebula.
During the growth of the Galactic Empire, Jedi Knight Empatojayos Brand was downed by Darth Vader close to the nebula, where he then plummeted through it and located the planet Ganath. Consequently, Brand ascended to become the king of the planet.
In an attempt to evade pursuing bounty hunters, the Millennium Falcon flew directly into the nebula, only to encounter Ganathan patrols. Boba Fett's ship, Slave I, initiated patrols around the perimeter of the nebula, awaiting the Falcon's emergence. After acquiring the lightning gun, the Falcon departed Ganath, sending Slave I spinning into the nebula's depths.