Heber Doust Curtis26 April 1920
Uses spiral nebulae including Andromeda in the Great Debate, arguing that they are external galaxies rather than small objects inside the Milky Way.
United States · Science / Astronomy. Chronological records rendered directly from the World History Database.
Uses spiral nebulae including Andromeda in the Great Debate, arguing that they are external galaxies rather than small objects inside the Milky Way.
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