celestial body vs space satellite

celestial body

noun
  • A natural object which is located outside of Earth's atmosphere, such as a comet, an asteroid, the Moon, a planet, the Sun, or a star. 

space satellite

noun
  • A crewed or robotic spacecraft designed to orbit the Earth 

How often have the words celestial body and space satellite occurred in a corpus of books? (source: Google Ngram Viewer )