The planet Rossak was the fifth planet in the star system HD95424. It was the fourth stop of Zensunni Wanderers during their forced migration times. Fifth planet of Alces Minor (Alpha Crateris)

In 10191 AG, the Lady Jessica experienced memories of Rossak when she underwent the spice agony on Arrakis. During the ceremony, Jessica successfully changed the Water of Life poison, thus unlocking her Other memories. It was during the induced trance that she recalled moments, through Other Memory, of the original Zensunni Wanderers on the planet Poritrin, as well as Zensunni women taking awareness spectrum narcotics that unlocked genetic memory for the first time.

The Fremen of Arrakis would recall the raiders pursuing them on Rossak, through courtyards lush with greenery. This recollection would normally take place during a ceremony, along with the raids on Poritrin and Bela Tegeuse.

Sources: Dune,

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