Harlow Shapley
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Shapley used Cepheid variable stars to estimate the size of the Milky Way Galaxy and the Sun's position within it. In 1953 he proposed his "liquid water belt" theory, now known as the concept of a habitable zone. Provided by Wikipedia
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Published: 1933
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 101
42
Published: 1933
Superior document: Annals of the Astronomical Observatory of Harvard College 90,1
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Published: 1938
Superior document: Annals of the astronomical observatory of Harvard College 106,1
44
Published: 1935
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 116
45
Published: 1934
Superior document: Annals of the Astronomical Observatory of Harvard College 90,5
46
Published: 1934
Superior document: Annals of the Astronomical Observatory of Harvard College 90,4
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Published: 1951
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 36
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Published: [1943]
Superior document: Annals of the astronomical observatory of Harvard College 109,11
51
Published: 1937
Superior document: Annals of the astronomical observatory of Harvard College 105