Al Dhanab is an "artificial world," location of a Bene Gesserit creche and "one of the original Sisterhood safe planets." A "planet of constant testing," it is considered "an equivalent of Salusa Secundus" and in some ways "worse than Dune." The environment is characterized by "high cliffs and dry gorges, hot winds and frigid winds, little moisture and too much." At some point the Sisterhood considers converting the whole planet into a no-chamber, but ultimately abandons the plan due to the prohibitive energy requirements. In the real world, Al Dhanab is the traditional star name for Gamma Gruis.
Read more about this topic: List Of Dune Planets