#astronomer__uranologist__stargazer  a physicist who studies astronomy
  supertype:  physicist  a scientist trained in physics
  instance:  Aristarchus_of_Samos  Friedrich_Wilhelm_Bessel  Nathaniel_Bowditch  Anders_Celsius  Nicolaus_Copernicus  Sir_Arthur_Stanley_Eddington  Eratosthenes  Galileo_Galilei  George_Ellery_Hale  Asaph_Hall  Edmond_Halley  Sir_Frederick_William_Herschel  Sir_John_Frederick_William_Herschel  Hipparchus  Edwin_Powell_Hubble  Sir_William_Huggins  Hypatia  Johannes_Kepler  Samuel_Pierpoint_Langley  Pierre_Simon_de_Laplace  Sir_Alfred_Charles_Bernard_Lovell  Percival_Lowell  Maria_Mitchell  Johann_Muller  Simon_Newcomb  Omar_Khayyam  Jan_Hendrix_Oort  Benjamin_Peirce  Ptolemy  David_Rittenhouse  Giovanni_Virginio_Schiaparelli  Harlow_Shapley  Willem_de_Sitter  Thales_of_Miletus  Clyde_William_Tombaugh
  subtype:  astrophysicist  an astronomer who studies the physical properties of celestial bodies
  subtype:  cosmologist  an astronomer who studies the evolution and space-time relations of the universe
     instance:  Georges_Henri_Lemaitre__Lemaitre__Edouard_Lemaitre

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