luminosity vs starlight

luminosity

noun
  • the rate at which a star radiates energy in all directions 

  • the state of being luminous, or a luminous object; brilliance or radiance 

  • the ratio of luminous flux to radiant flux at the same wavelength; the luminosity factor 

starlight

noun
  • Light emitted from stars other than the Sun. 

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