tarso'imei lujvo

s1 is a/the galaxy (default is the Milky Way)

Cf. tarci, so'imei, sostartai, tarboi, tarci'e, "galki" (which is a gismu and does not reference stars specifically).

In notes:

x1 = tai1 is a constellation of stars x2 = tar1 (set, quantity, region), according to standard x3.
b1 is a globular cluster consisting of stars with properties t2.
c1 is a solar/stellar system based on star(s) t1 (default is the Solar System) with stellar properties t2 with components c3 displaying c4 (ka).
tarm1 tartai tarc2.
x1 [mass of properties describing skills, technological advances] is a civilization of x2 (mass of persons) manifesting Type x3 (number) on the Kardashev scale of technological advancement according to standard/particular scale/definition x4.