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: 1948
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 24
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Published: 1934
Superior document: Annals of the astronomical observatory of Harvard College 88,4
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Published: 1949
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 29
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Published: 1953
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 50
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Published: 1933
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 90
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Published: 1929
Superior document: Studies of the galactic center 4
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Published: 1937
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 140
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Published: 1928
Superior document: Studies of the galactic center 3
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Published: 1951
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series II 37
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Published: 1933
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 102
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Published: 1939
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 158
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Published: 1939
Superior document: Galactic and extragalactic studies 1
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Published: 1938
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 154
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Published: 1939
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 187
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Published: 1944
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 255
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Published: 1933
Superior document: Reprints / The Astronomical Observatory of Harvard College : Series I 81
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