The Brim is an area of peripheral planets, not populous enough to participate in the Assembly. The planets on the other side of the currentstream have numbers instead of names.
One of those planets is called P1104. Yma Zetsyvis has some familiarity with it, though Shotet are forbidden from associating with any fringe planets to avoid associating the Shotet nation with such other low-level groups.
Ast is from a Brim planet.