Sittuun were a race of grey, bald humanoids from the Battani-045 system.
The Sittuun were grey, bald humanoids with black dotty eyes, no noses, and simple mouths. Their blood was some form of blue-green colour mix, for when they blushed, their cheeks turned turquoise. (PROSE: Night of the Humans)
The Sittuun were quite capable of speaking human languages, but their native tongue could not be spoken or understood by humans. They often used human names for themselves and things in their society as a way of being understandable to their human neighbours. (PROSE: Night of the Humans)
The Sittuun were responsible for the Beagle XXI mission, which sent eleven of their race to Gyre to destroy the planet in order to avoid widespread devastation to nearby systems upon collision with the comet Schuler-Khan. Captain Jamal al-Jehedeh and Lt Baasim al-Jehedeh were of the race, and among the group of eleven on the mission. (PROSE: Night of the Humans)