What it describes is beautiful. A sorely missed distinction leading to a common misconception. Maybe Gustav Holst was right after all?
i didn't think music 'described' anything, in the way a picture or language might be considered to 'represent' a state of affiars. It's the most abstract art, in this sense. Music could be considered beautiful in the way maths is considered beautiful. It is structural and elegant. However music is not completely mathematics or structure emobodied in divisions of tone. A metal tune played on a piano is NOT going to sound as good! There is something textural, which might be emotional, i'm not sure there.
Holst is amazing!