It is not the moon, but half moon—the crescent moon—above the head, not hair
of Lord Shiva. Half moon symbolizes timelessness that self-perpetuates the
moon. Head symbolizes the phase (Charan), specifically metaphysical or lunar
phase. Lord Shiva is the timelessness phase. He is the perfect goal for a
sentient entity to be conscious that it is an entity whose conscious energy is the
origin of life, and the blessing to fulfill all wishes.