empyrean vs heavens

empyrean

noun
  • The region of pure light and fire; the highest heaven, where the pure element of fire was supposed by the ancients to exist: the same as the ether, the ninth heaven according to ancient astronomy, and Dante's poem. 

adj
  • Of the sky or the heavens; celestially refined. 

heavens

noun
  • The distant sky of the sun, moon, and stars. 

intj
  • An expression of surprise, contempt, outrage, disgust, boredom, or frustration. 

How often have the words empyrean and heavens occurred in a corpus of books? (source: Google Ngram Viewer )