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189:, who also argued that the "spiral nebulae" were extragalactic). He showed that there were more novae in Andromeda than in the Milky Way. From this, he could ask why there were more novae in one small section of the galaxy than the other sections of the galaxy, if Andromeda were not a separate galaxy but simply a nebula within Earth's galaxy. This led to supporting Andromeda as a separate galaxy with its own signature age and rate of nova occurrences. Curtis also noted the large
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The two scientists first presented independent technical papers about "The Scale of the
Universe" during the day and then took part in a joint discussion that evening. Much of the lore of the Great Debate grew out of two papers published by Shapley and by Curtis in the May 1921 issue of the
256:, which does indeed temporarily outshine the combined output of an entire galaxy. On other points, the results were mixed (the actual size of the Milky Way is in between the sizes proposed by Shapley and Curtis), or in favor of Shapley (the
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rotating, and that if the
Pinwheel Galaxy were in fact a distinct galaxy and could be observed to be rotating on a timescale of years, its orbital velocity would be enormous and there would be a violation of the universal speed limit, the
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In the aftermath of the public debate, scientists have been able to verify individual pieces of evidence from both astronomers, but on the main point of the existence of other galaxies, Curtis has been proven correct.
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The format of the great debate has been used subsequently to argue the nature of fundamental questions in astronomy. In honor of the first "Great Debate", the
Smithsonian has hosted four more events.
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were simply part of the Milky Way. He backed up this claim by appealing to their relative sizes—if
Andromeda were not part of the Milky Way, then its distance must have been on the order of 10
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in the
Andromeda "nebula" that had briefly outshone the entire nebula, constituting a seemingly impossible output of energy were Andromeda in fact a separate galaxy.
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105:(then thought to be the entire Universe), while Curtis held that they were in fact independent galaxies, implying that they were exceedingly large and distant.
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rotating were correct, he himself would have been wrong about the scale of the
Universe and that the Milky Way would fully encompass it.
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stars, proving that Curtis was correct. It is now known that the Milky Way is only one of as many as an estimated 200 billion (
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was near the center of the galaxy in Curtis's model, while
Shapley correctly placed the Sun in the outer regions of the galaxy).
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113:. The published papers each included counterarguments to the position advocated by the other scientist at the 1920 meeting.
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Curtis, on the other hand, contended that
Andromeda and other such "nebulae" were separate galaxies, or "
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It later became apparent that van Maanen's observations were incorrect—one cannot actually see the
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1920 debate between Harlow
Shapley and Heber Curtis on whether there were other galaxies
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was over whether this was a cloud of gas and dust or a distant galaxy.
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showed that
Andromeda was far outside the Milky Way by measuring
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Gott III, J. R.; et al. (2005). "A Map of the Universe".
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174:. Shapley also backed up his claims with the observation of a
328:. Springer Science & Business Media. pp. 164–165.
351:"Novae in Spiral Nebulae and the Island Universe Theory"
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Measuring the Universe: The Cosmological Distance Ladder
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Publications of the Astronomical Society of the Pacific
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Publications of the Astronomical Society of the Pacific
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Curtis stated that if van Maanen's observation of the
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193:of spiral nebulae that suggested they could not be
185:" (a term invented by the 18th-century philosopher
145:is the entirety of the Universe. He argued that "
30:For other topics known as "great debates", see
505:Christopher J. Conselice; et al. (2016).
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209:found in Earth's own galaxy, explaining the
161:would not accept. Shapley cited the work of
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566:"Two Trillion Galaxies, at the Very Least"
689:(The original publication of the debate.)
673:Bulletin of the National Research Council
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205:present in other galaxies similar to the
111:Bulletin of the National Research Council
698:(Resources related to the debate at the
296:"NRC Transcripts of `Great Debate' Page"
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201:-model universe. In addition, he cited
93:. It concerned the nature of so-called
639:An Introduction to Modern Astrophysics
637:Carroll, B. W.; Ostlie, D. A. (2017).
593:"Why the 'Great Debate' was important"
317:
315:
83:Smithsonian Museum of Natural History
7:
1260:Noisy intermediate-scale quantum era
427:"The Great Debate - 100 years later"
141:Shapley presented the case that the
694:"The Shapley–Curtis Debate in 1920"
667:Shapley, H.; Curtis, H. D. (1921).
564:Fountain, Henry (17 October 2016).
81:, was held on 26 April 1920 at the
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349:Curtis, Heber D. (January 1988).
129:The "Great Spiral Nebula" in the
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1421:Astronomy in the United States
1:
679:(Part 3, Issue 11): 171–217.
425:Evans, Ben (April 25, 2020).
32:Great Debate (disambiguation)
621:"Great Debates in Astronomy"
1182:Cosmic microwave background
669:"The scale of the universe"
601:Goddard Space Flight Center
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643:Cambridge University Press
542:10.3847/0004-637X/830/2/83
157:—a span most contemporary
85:, between the astronomers
29:
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511:The Astrophysical Journal
453:The Astrophysical Journal
413:Carroll & Ostlie 2017
398:Carroll & Ostlie 2017
1411:1920 in Washington, D.C.
172:speed of light in vacuum
1317:Chandrasekhar–Eddington
1243:Golden age of cosmology
1175:On specific discoveries
1123:Lorentz transformations
133:(1902 photograph). The
131:constellation Andromeda
1248:Medieval Islamic world
991:Computational physics
933:Variational principles
860:Electrical engineering
322:Webb, Stephen (1999).
197:to the Milky Way in a
138:
1238:Golden age of physics
1233:Copernican Revolution
195:gravitationally bound
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79:Shapley–Curtis Debate
1396:History of astronomy
1341:Relativity priority
1196:Subatomic particles
1156:Loop quantum gravity
1145:Quantum information
1094:Quantum field theory
894:Gravitational theory
706:Trimble, V. (1995).
228:Later in the 1920s,
97:and the size of the
1305:Scientific disputes
1291:Via Panisperna boys
1192:Gravitational waves
1139:Recent developments
870:Maxwell's equations
729:1995PASP..107.1133T
685:1921BuNRC...2..171S
533:2016ApJ...830...83C
476:2005ApJ...624..463G
367:1988PASP..100....6C
275:Other Great Debates
1406:Physical cosmology
1401:Scientific debates
1350:General relativity
1345:Special relativity
1286:Oxford Calculators
1113:Special relativity
1032:General relativity
817:History of physics
571:The New York Times
163:Adriaan van Maanen
139:
77:, also called the
64:Heber Doust Curtis
1383:
1382:
1357:Transfermium Wars
1276:Harvard Computers
1101:Subatomic physics
1074:Quantum mechanics
1010:Superconductivity
1001:Condensed matter
830:Classical physics
652:978-1-108-42216-1
244:) to 2 trillion (
211:zone of avoidance
191:radial velocities
16:(Redirected from
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1296:Women in physics
1048:Nuclear physics
972:Perpetual motion
906:Material science
850:Electromagnetism
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224:After the debate
183:island universes
103:Milky Way galaxy
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18:The great debate
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945:Spectroscopy
887:Aerodynamics
865:Field theory
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631:Bibliography
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604:. Retrieved
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230:Edwin Hubble
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91:Heber Curtis
78:
75:Great Debate
74:
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51:(1885 –1972)
1205:Higgs boson
207:dust clouds
159:astronomers
155:light years
66:(1872–1942)
1390:Categories
1226:By periods
1044:Geophysics
1016:Cosmology
606:2009-10-16
577:17 October
524:1607.03909
436:2020-09-10
305:2024-03-29
283:References
203:dark lanes
149:" such as
1269:By groups
1253:Astronomy
1089:Molecules
923:Mechanics
838:Astronomy
768:Astronomy
745:122365368
517:(2): 83.
385:0004-6280
254:supernova
151:Andromeda
143:Milky Way
121:Arguments
1375:Category
1200:timeline
1187:Graphene
1149:timeline
1118:timeline
1106:timeline
1079:timeline
1020:timeline
1005:timeline
995:timeline
957:timeline
928:timeline
911:timeline
899:timeline
882:timeline
855:timeline
843:timeline
821:timeline
723:: 1133.
702:website)
551:17424588
99:Universe
1210:Neutron
1067:Weapons
1052:Fission
967:Entropy
754:Portals
725:Bibcode
681:Bibcode
529:Bibcode
492:9654355
472:Bibcode
363:Bibcode
199:Kapteyn
1057:Fusion
962:Energy
940:Optics
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135:Debate
1128:tests
1084:Atoms
1062:Power
1037:tests
780:Space
741:S2CID
711:(PDF)
547:S2CID
519:arXiv
488:S2CID
462:arXiv
361:: 6.
700:NASA
647:ISBN
597:NASA
579:2016
381:ISSN
330:ISBN
176:nova
89:and
73:The
733:doi
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537:doi
515:830
480:doi
458:624
371:doi
359:100
258:Sun
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405:^
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