fixed orbit

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A fixed orbit is the concept, in atomic physics, where an electron is considered to remain in a specific orbit, at a fixed distance from an atom's nucleus, for a particular energy level.{{cite web | access-date=2019-10-03 | url=https://history.aip.org/history/exhibits/heisenberg/p05c.htm | title=Student Years, 1920–1927: The Old Quantum Theory | series=Werner Heisenberg and the Uncertainty Principle | url-status=dead | website=American Institute of Physics | archive-date=2019-10-03 | archive-url=https://web.archive.org/web/20191003092800/https://history.aip.org/history/exhibits/heisenberg/p05c.htm }}{{cite book | first1=Steven S. | first2=Donald J. | last1=Zumdahl | url=https://books.google.com/books?id=2KR0sYkqSPkC | title=Introductory Chemistry: A Foundation | publisher=Cengage Learning | last2=DeCoste | year=2007 | isbn=978-0-618-80327-9}}

The concept was promoted by quantum physicist Niels Bohr c. 1913.{{cite web | access-date=2019-10-03 | archive-date=2003-01-17 | archive-url=https://web.archive.org/web/20030117180003/http://www.fordhamprep.org/gcurran/sho/sho/lessons/lesson32.htm | url=http://www.fordhamprep.org/gcurran/sho/sho/lessons/lesson32.htm | title=Lesson 3-2 The Development of the Atomic Model | date=2001 | last=Curran | first=Gregory L | url-status=dead | website=fordhamprep.org }}{{cite web | access-date=2019-10-03 | url=http://www.brooklyn.cuny.edu/bc/ahp/LAD/C3/C3_elecPos_02.html | title=The Quantum Atom – BIOdotEDU | date=2003 | last=Blamire | first=John | website=www.brooklyn.cuny.edu}}

The idea of the fixed orbit is considered a major component of the Bohr model (or Bohr theory).