Astral - pertaining to the Astral Realm, but does not necessarily mean ethereal, immortal, or divine
Ethereal - from the Astral Realm and is more mystical/magical, but does not necessarily mean immortal
Immortal - can be from the Astral Realm or Spiritual Realm, and typically is connected to the power or magic derived from, or associated with, Immortal beings
Divine - can be from the Astral Realm or Spiritual Realm, and is more spiritual than mystical or magical