Inverted snub dodecadodecahedron

The inverted snub dodecadodecahedron or isdid, is a uniform polyhedron. It consists of 60 snub triangles, 12 pentagrams, and 12 pentagons. Three triangles, 1 pentagon, and one pentagram meeting at each vertex. It can be constructed by alternation of the quasitruncated dodecadodecahedron and then setting all edge lengths to be equal.

Measures
The circumradius of the inverted snub dodecadodecahedron with unit edge length is a real root of: $$64x^8-192x^6+180x^4-65x^2+8$$