A question came to me all of a sudden, that I could have asked myself many years ago: how did you choose the names of the stars of the Cetagnada Empire? Of course the simple answer "any random greek letters as is usual for naming stars in any constellation" seemed sufficient to me, for years.
But suddenly I realized something: except for Mu, all the others you actually name (Eta, Rho, Xi, Sigma - the othar three are never named) are names of elementary particles in Gell-Mann's "Eightfold Way". Also, Eta is the capital of the Eight-Stars Cetaganda Empire, and Eta is the only particle among those whose names you used, that sits at the center of one octet (namely, the scalar meson octet).
As for Mu, it is a historical fact that Yukawa predicted the existence of a particle, later found and called Pi (and that belongs to the Gell-Mann's Eightfold way), but when the first ever artificial subatomic particle was discovered and called Mu, it was thought for some time to be Yukawa's one. So if you did not want a "Pi(e) in the Sky", changing the name into Mu made some kind of sense, because of this original confusion.
Did I guess correctly, or do I see too much in your naming scheme?
If I am right, we now know the name of the three other stars of the Empire: Phi Ceta, Omega Ceta and Lambda Ceta. Indeed these are the only remaining greek-letter names of particles that sit in octets (except that there would be a problem of precedence with Eta Ceta, since all three also sit at the center of some octet)!
Human is as human does....Animals don't weep, Nine
LMB, The Labyrinth