In astronomy, The Great Debate, also called the Shapley - Curtis Debate was an influential debate between the astronomers Harlow Shapley and Heber Curtis which concerned the nature of spiral nebulae and the size of the universe. Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study Harlow Shapley ( November 2 1885 &ndash October 20 1972) was an American Astronomer. Heber Doust Curtis ( June 27 1872 – January 9 1942) was an American Astronomer. A spiral galaxy is a Galaxy belonging to one of the three main classes of galaxy originally described by Edwin Hubble in his 1936 work “The Realm of the A nebula (from Latin: "mist" pl nebulae or nebulæ, with ligature or nebulas) is an Interstellar cloud of The Universe is defined as everything that Physically Exists: the entirety of Space and Time, all forms of Matter, Energy The basic issue under debate was whether distant nebulae were relatively small and lay within our own galaxy or whether they were large, independent galaxies. A galaxy is a massive gravitationally bound system consisting of Stars an Interstellar medium of gas and dust, and Dark matter The debate took place on 26 April 1920 in the Baird auditorium of the Smithsonian Museum of Natural History. Events 1467 - The miraculous image in Our Lady of Good Counsel appear in Genazzano, Italy. Year 1920 ( MCMXX) was a Leap year starting on Thursday (link will display 1920 of the Gregorian calendar The Smithsonian Institution (smɪθsoʊnɪən is an educational and research institute and associated Museum complex administered and funded by the Government of The National Museum of Natural History is a Natural history Museum administered by the Smithsonian Institution, located on the National 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 Curtis in the May 1921 issue of the Bulletin of the National Research Council. Year 1921 ( MCMXXI) was a Common year starting on Saturday (link will display full 1921 calendar of the Gregorian calendar The National Research Council (NRC of the USA is the working arm of the United States National Academy of Sciences and the United States National Academy of The published papers each included counter arguments to the position advocated by the other scientist at the 1920 meeting. A scientist, in the broadest sense refers to any person that engages in a systematic activity to acquire Knowledge or an individual that engages in such practices
Shapley was arguing in favor of the Milky Way as the entirety of the universe. The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias sometimes referred to simply He believed galaxies such as Andromeda and the Spiral Nebulae were simply part of the Milky Way. The Andromeda Galaxy (ænˈdrɒmədə also known as Messier 31, M31, or NGC 224; often referred to as the Great Andromeda He could back up this claim by citing relative sizes—if Andromeda and such were not part of the Milky Way, then the distance to it be in the order of 108 light years—a span most astronomers would not accept. A light-year or light year (symbol ly) is a unit of Length, equal to just under ten trillion Kilometres As defined by Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study Adriaan van Maanen was also providing evidence to Shapley's argument. Adriaan van Maanen ( March 31 1884, Sneek &ndash January 26 1946, Pasadena) was a Dutch - American Maanen was a well respected astronomer of the time who said he had observed Andromeda rotating. If Andromeda was in fact a distinct galaxy and could be observed to be rotating, there would clearly be a violation of the universal speed limit, the speed of light.
Curtis on the other side contended that Andromeda and other such nebulae were separate galaxies, or "Island universes". He showed that there were more novae in Andromeda than in the Milky Way. A supernova (plural supernovae or supernovas) is a stellar Explosion. From this he could ask why there were more novae in one small section of the galaxy than the others. This led to supporting Andromeda as a separate galaxy with its own signature age and rate of novae occurrences. He also cited dark lanes present in other galaxies similar to the dust clouds found in our own galaxy and massive doppler shifts found in other galaxies. The Doppler effect (or Doppler shift) named after Christian Doppler, is the change in Frequency and Wavelength of a Wave for
Curtis stated that if van Maanen's observation of Andromeda rotating were correct, he himself would have been wrong about the scale of the universe and that the Milky Way would fully encompass it. It later became apparent that van Maanen's observations were completely false—one can not actually see Andromeda rotate during a human lifespan. Life expectancy is the average number of years of life remaining at a given age It is now known that the Milky Way is only one of hundreds of billions of galaxies in the visible universe, proving Curtis the more accurate party in the debate in that respect. In Big Bang Cosmology, the observable universe is the region of space bounded by a Sphere, centered on the observer that is small enough that 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 (Curtis' galaxy was centered on the Sun, while Shapley correctly placed the Sun in the outer regions on the galaxy). [1]
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The Universe is defined as everything that Physically Exists: the entirety of Space and Time, all forms of Matter, Energy A galaxy is a massive gravitationally bound system consisting of Stars an Interstellar medium of gas and dust, and Dark matter The Andromeda Galaxy (ænˈdrɒmədə also known as Messier 31, M31, or NGC 224; often referred to as the Great Andromeda The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Γαλαξίας (Galaxias sometimes referred to simply Astronomy (from the Greek words astron (ἄστρον "star" and nomos (νόμος "law" is the scientific study The National Aeronautics and Space Administration ( NASA, ˈnæsə is an agency of the United States government, responsible for the nation's public space programDapyx Software network: MP3 Explorer | Ebook Manager | Zenithic