View source for Williamina Fleming

{{Short description|Scottish astronomer (1857–1911)}}
{{Use dmy dates|date=May 2020}}
{{Use American English|date=February 2019}}<!-- Lived in the US & notable for her work there. -->
{{Infobox scientist
| name              = Williamina Fleming
| image             = Williamina Paton Stevens Fleming circa 1890s.jpg
| image_size        = 200px
| alt               = Black and white portrait photograph of Williamina Paton Stevens Fleming
| caption           = Fleming, c. 1890s
| birth_name        = Williamina Paton Stevens
| birth_date        = {{Birth date|df=y|1857|5|15}}
| birth_place       = [[Dundee]], Scotland
| death_date        = {{death date and age|df=y|1911|5|21|1857|5|15}}
| death_place       = [[Boston]], Massachusetts, United States
| citizenship       = 
| nationality       = Scottish
| field             = [[Astronomy]]
| workplaces        = [[Harvard College Observatory]]
| alma_mater        = None
| doctoral_advisor  = 
| doctoral_students = 
| known_for         = 
| author_abbrev_bot = 
| author_abbrev_zoo = 
| influences        = 
| influenced        = 
| prizes            = 
| religion          = 
| footnotes         = 
| signature         = Signature of Williamina Paton Stevens Fleming (1857–1911).png
}}

'''Williamina Paton Stevens Fleming''' (15 May 1857 – 21 May 1911) was a Scottish [[astronomer]].<ref name=":2">{{Cite web |last=McLauchlan |first=Richard |date=2024-12-28 |title=Meet the most influential Scots you've probably never heard of |url=https://www.thetimes.com/uk/scotland/article/six-of-the-most-influential-scots-youve-probably-never-heard-of-8922ghhwv?utm_source=chatgpt.com&region=global |access-date=2025-01-22 |website=www.thetimes.com |language=en}}</ref> At the [[Harvard College Observatory]], she contributed to the photographic classification of [[stellar spectra]], helping to develop a common designation system for stars. Fleming cataloged more than ten thousand stars, 59 gaseous [[nebula]]e, over 310 [[variable star]]s, and 10 [[nova]]e, among other astronomical phenomena. She is credited with the discovery of the [[Horsehead Nebula]] in 1888, and she was a vocal supporter of women's representation in her field.

==Early life==
Williamina Paton Stevens was born in [[Dundee]], Scotland, at 86 Nethergate,<ref>{{Cite web |title=WilliaminaFleming |url=https://scientificwomen.net/women/fleming-williamina-37 |access-date=2024-06-06 |website=Scientific Women}}</ref> on 15 May 1857 to Mary Walker and Robert Stevens, a carver and gilder. She was one of six children.<ref name="Ewan Innes Reynolds 2006 p. 121">{{cite book |last1=Ewan |first1=Elizabeth |last2=Innes |first2=Sue |last3=Reynolds |first3=Sian |title=The biographical dictionary of Scottish women: from the earliest times to 2004 |location=Edinburgh, Scotland |publisher=Edinburgh University Press |year=2006 |isbn=978-0748626601 |oclc=367680960 |page=121 |url={{Google books|Zs6qBgAAQBAJ|page=121|plainurl=yes}} |access-date=14 February 2019}}</ref> Her younger sister, Johanna Stevens, would also later work at Harvard College Observatory.<ref>{{Cite web |title=Johanna Mackie |url=https://library.cfa.harvard.edu/women-at-hco/johanna-mackie |access-date=2024-03-25 |website=library.cfa.harvard.edu |language=en}}</ref> Starting at the age of fourteen, she went to work as a [[pupil-teacher]]. In 1877, she married James Orr Fleming, an accountant and widower, also of Dundee.<ref name=":0">{{cite web |url=http://ocp.hul.harvard.edu/ww/fleming.html |website=Harvard University Library Open Collections Program|title= Women Working 1800–1930, Williamina Paton Stevens Fleming (1857–1911)|access-date= 28 August 2017|archive-url=https://web.archive.org/web/20180402041723/http://ocp.hul.harvard.edu/ww/fleming.html|archive-date=2 April 2018}} With links to manuscripts and other resources.</ref> The couple had one son, Edward P. Fleming.<ref name="Cannon">{{cite journal |last=Cannon |first=Annie J. |author-link=Annie Jump Cannon |date=June 1911 |title=Williamina Paton Fleming |url=https://zenodo.org/record/1448062 |journal=Science |publication-date=30 June 1911 |volume=33 |issue=861 |pages=987–988 |bibcode=1911Sci....33..987C |doi=10.1126/science.33.861.987 |pmid=17799863}}
</ref>

==Career==
In 1878, aged 21, she and her husband emigrated to Boston, Massachusetts, US.<ref name=":0"/> After her husband abandoned her and her young son, she worked as a maid in the home of Professor [[Edward Charles Pickering]], the director of the [[Harvard College Observatory]] (HCO). Pickering's wife Elizabeth recommended Williamina as having talents beyond custodial and maternal arts, and in 1879, Pickering hired Fleming to conduct part-time administrative work at the observatory.<ref name=":12">{{cite book|title=The Glass Universe|last=Sobel|first=Dava|date=2016|publisher=Viking|isbn=978-0698148697|pages=xii}}</ref>

In 1881, Pickering formally invited Fleming to join the HCO and taught her how to analyze stellar spectra. She became one of the founding members of the [[Harvard Computers]], an all-women cadre of [[human computer]]s hired by Pickering to compute mathematical classifications and edit the observatory's publications.<ref name=":1">{{Cite web |title=Williamina Paton Fleming |url=https://www.projectcontinua.org/williamina-paton-fleming/}}</ref>

[[File:Astronomer Edward Charles Pickering's Harvard computers.jpg|thumb|The [[Harvard Computers]], the group of women computers at the Harvard College Observatory, who worked for the astronomer Edward Charles Pickering. The group included Harvard computer and astronomer [[Henrietta Swan Leavitt]], [[Annie Jump Cannon]], Williamina Fleming, and [[Antonia Maury]].]]

===Henry Draper Catalogue, 1886===
In 1886, [[Mary Anna Draper]], the wealthy widow of astronomer [[Henry Draper]], started the Henry Draper Memorial to fund the HCO's research.<ref>{{cite journal |title=On the Henry Draper Memorial Photographs of Stellar Spectra |last=Barker |first=George F. |year=1887 |url=https://books.google.com/books?id=KcAAAAAAYAAJ |journal=Proceedings of the American Philosophical Society |volume=24 |pages=166–172 }}</ref><ref>{{cite book |last=Ogilvie |first=Marilyn Bailey |year=1986 |title=Women in Science: Antiquity Through the Nineteenth Century: a Biographical Dictionary with Annotated Bibliography |url=https://archive.org/details/womeninscience00mari |url-access=registration |page=[https://archive.org/details/womeninscience00mari/page/75 75] |publisher=MIT Press |isbn=978-0-262-65038-0 }}</ref> In response, the HCO began work on the first [[Henry Draper Catalogue]], a long-term project to obtain the optical spectra of as many stars as possible and to index and classify stars by spectra.<ref>{{Cite journal |bibcode = 1915JRASC...9..203C|title = The Henry Draper Memorial|journal = Journal of the Royal Astronomical Society of Canada|volume = 9|pages = 203|last1 = Cannon|first1 = Annie J.|year = 1915 }}</ref>

Fleming was placed in charge of the Draper Catalogue project.<ref name=":1" /> A disagreement soon developed regarding classifying the stars.<ref name=":12" /> The analysis had been started by Nettie Farrar, but she left a few months later to be married. [[Antonia Maury]] advocated for a complex classification scheme. Fleming, however, wanted a much more simple, straightforward approach.<ref name=Mack1990>{{cite book |last=Mack |first=Pamela |chapter=Straying from their orbits: Women in astronomy in America |editor-first1=G. |editor-last1=Kass-Simon |editor-first2=Patricia |editor-last2=Farnes |editor-first3=Deborah |editor-last3=Nash |year=1990 |title=Women of Science: Righting the Record |location=Bloomington, IN, US |publisher=Indiana University Press |page=[https://archive.org/details/womenofsciencer000kass/page/99 99] |access-date=1 April 2014 |chapter-url=https://books.google.com/books?id=Ez7DCJM57esC |isbn=9780253208132 |oclc=28112853 |url=https://archive.org/details/womenofsciencer000kass/page/99 }}</ref>

The latest Harvard College Observatory images contained photographed spectra of stars that extended into the ultraviolet range, which allowed much more accurate classifications than recording spectra by hand through an instrument at night.<ref name=":12" /> Fleming devised a system for classifying stars according to the relative amount of [[hydrogen]] observed in their [[spectrum|spectra]], known as the Pickering-Fleming system.<ref name=Britannica>{{Britannica | id=209979 }}</ref> Stars showing hydrogen as the most abundant element were classified A; those of hydrogen as the second-most abundant element, B; and so on.

Later, her colleague [[Annie Jump Cannon]] reordered the classification system based on the surface temperature of stars, resulting in the [[Harvard spectral classification]], which is still in use today.<ref name=Geiling2013>{{cite web |url=https://www.smithsonianmag.com/history/the-women-who-mapped-the-universe-and-still-couldnt-get-any-respect-9287444/ |title=The Women Who Mapped the Universe And Still Couldn't Get Any Respect |website=Smithsonian Magazine |date= 18 September 2013  |author=Natasha Geiling |access-date= 19 February 2019}}</ref>

In 1890, the HCO published the first [[Henry Draper Catalogue]] due to years of work by their female computer team, a catalog with more than 10,000 stars classified according to their spectrum. Fleming did the majority of these classifications.<ref>Harvard University. [https://platestacks.cfa.harvard.edu/about-collection "About the Collection"] {{Webarchive|url=https://web.archive.org/web/20191207080617/https://platestacks.cfa.harvard.edu/about-collection |date=7 December 2019 }}, ''[[Harvard.edu]]''.</ref>{{when|date=October 2017}} Fleming also made it possible to go back and compare recorded plates by organizing thousands of photographs by telescope along with other identifying factors.<ref name=":12" /> In 1898, she was appointed Curator of Astronomical Photographs at Harvard, the first woman to hold the position.<ref name=Britannica />

At the 1893 [[World's Fair in Chicago]], Fleming openly advocated for other women in the sciences in her talk "A Field for Woman's Work in Astronomy", where she openly promoted hiring female assistants in astronomy. Her speech suggested she agreed with the prevailing idea that women were inferior but felt that, if given more significant opportunities, they would be able to become equals; in other words, the sex differences in this regard were more culturally constructed than biologically grounded.<ref>{{Cite journal|last=Rossiter|first=Margaret W.|date=1980|title="Women's Work" in Science, 1880–1910|jstor=230118|journal=Isis|volume=71|issue=3|pages=381–398|doi=10.1086/352540|s2cid=143706974}}</ref>

===Notable discoveries===
During her career, Fleming discovered a total of 59 gaseous [[nebula]]e, over 310 [[variable star]]s, and 10 [[nova]]e.<ref name=":0"/> This includes the [[Horsehead Nebula]] and [[V Persei]].
[[File:Delegates to the Fourth Conference International Union for Cooperation in Solar Research at Mount Wilson Observatory.jpg|thumb|Fleming, center right, at the Fourth Conference International Union for Cooperation in Solar Research at [[Mount Wilson Observatory]], 1910|350x350px]]

In 1888, Fleming discovered the [[Horsehead Nebula]]<ref name="Cannon" /> on a telescope-[[photogrammetry]] plate made by astronomer [[W. H. Pickering]], brother of E.C. Pickering. She described the bright nebula (later known as [[IC 434]]) as having "a semicircular indentation 5 minutes in diameter 30 minutes south of [[Zeta Orionis]]". Subsequent professional publications neglected to give credit to Fleming for the discovery. The first [[Dreyer Index Catalogue]] omitted Fleming's name from the list of contributors, having then discovered sky objects at Harvard, attributing the entire work merely to "Pickering". However, by the time the second Dreyer Index Catalogue was published in 1908, Fleming and her female colleagues at the HCO were sufficiently well-known and received proper credit for their discoveries.

Fleming is also credited with the discovery of the first [[white dwarf]]:{{Dubious|date=August 2025|reason=Conflicting information with [[White dwarf]]}}

{{quote
|text=The first person who knew of the existence of white dwarfs was Mrs. Fleming; the next two, an hour or two later, Professor E. C. Pickering and I. With characteristic generosity, Pickering had volunteered to have the spectra of the stars which I had observed for parallax looked up on the Harvard plates. All those of faint absolute magnitude turned out to be of class G or later. Moved with curiosity I asked him about the companion of 40 Eridani. Characteristically, again, he telephoned to Mrs. Fleming who reported within an hour or so, that it was of Class A. 
|author=Henry Norris Russell<ref>{{Cite journal|last=Russell|first=Henry Norris|date=June 1944|title=Notes on white dwarfs and small companions|journal=The Astronomical Journal|volume=51|pages=13|bibcode=1944AJ.....51...13R|doi=10.1086/105780|doi-access=free}}</ref>
}}

In 1910, Fleming published her discovery of white dwarf stars.<ref name=":0" /> Her other notable publications include ''A Photographic Study of Variable Stars'' (1907), a list of 222 [[variable star]]s she had discovered; and ''Spectra and Photographic Magnitudes of Stars in Standard Regions'' (1911).

She became a US citizen in 1907.<ref>{{Cite web |title=Williamina Fleming |url=https://www.lindahall.org/about/news/scientist-of-the-day/williamina-fleming |access-date=2022-12-17 |website=The Linda Hall Library |language=en-US}}</ref>

She died of pneumonia in Boston on 21 May 1911,<ref name="Cannon"/><ref name=":0" /><ref>{{Cite web|url=https://scientificwomen.net/women/fleming-williamina-37|title=Williamina&nbsp;FLEMING|website=scientificwomen.net}}</ref> aged 54.

==Honors==
* Member of the [[Astronomical and Astrophysical Society of America]] and the Astronomical Society of France<ref name="Cannon"/>
* Honorary member of the [[Royal Astronomical Society]] of London in 1906, the first American woman to be elected<ref name=":0" />
* Guadalupe Almendaro Medal by the {{Interlanguage link multi|Astronomical Society of Mexico|es|3=Sociedad Astronómica de México|vertical-align=sup}}<ref>{{Cite web |title=Inicio {{!}} Sociedad Astronomica de México AC |url=https://www.sociedadastronomicademexico.org/ |access-date=2024-03-20 |website=Sociedad Astronómica |language=es}}</ref> for her discovery of new stars 
* Honorary fellow in astronomy of [[Wellesley College]]
* Commemorated on the Dundee Women's Trail<ref>{{cite web | title=Williamina Fleming | website=Dundee Women's Trail | date=December 7, 2020 | url=https://www.dundeewomenstrail.org.uk/womens-trail/williamina-fleming/ | access-date=December 13, 2024}}</ref>

==Legacy==
* The [[Fleming (crater)|Fleming]] [[lunar crater]] was jointly named after her and (not closely related) [[Alexander Fleming]]
* The asteroid [[5747 Williamina]] is named after her.<ref>{{Cite web |url=https://www.iau.org/static/publications/wgsbn-bulletins/wgsbn-bulletin-2201.pdf |title=IAU, WGSBN Bulletin, vol. 2, n. 1, 17 January 2022 |access-date=28 January 2022 |archive-date=29 December 2024 |archive-url=https://web.archive.org/web/20241229225415/https://www.iau.org/static/publications/wgsbn-bulletins/wgsbn-bulletin-2201.pdf |url-status=dead }}</ref>
* [[Kathryn Lasky]] published a book in 2021 about Fleming illustrated by Julianna Swaney called "She Caught the Light: Williamina Stevens Fleming: Astronomer" aimed at young people.<ref>{{Cite book |title=She Caught the Light: Williamina Stevens Fleming: Astronomer |isbn=978-0-06-284930-4 |language=en}}</ref>
In 2015, Lindsay Smith Zrull, curator of Harvard's Plate Stacks collection, was working to catalog and digitize the astronomical plates for [[Digital Access to a Sky Century @ Harvard]] (DASCH) and discovered about 118 boxes, each containing 20 to 30 notebooks, from women computers and early Harvard astronomers. Smith Zrull realized that the 2,500+ volumes were outside the scope of her work with DASCH but wanted to see the material preserved and made accessible. Smith Zrull contacted librarians at the [[Harvard–Smithsonian Center for Astrophysics]].{{Citation needed|date=August 2025}} 

In response, the Wolbach Library launched Project PHaEDRA (Preserving Harvard's Early Data and Research in Astronomy).<ref name=phaedra>{{cite web |url=https://www.bbc.co.uk/news/world-us-canada-40879870 |title=Unearthing the legacy of Harvard's female 'computers'|website=BBC News |date=28 August 2017  |author=Alex Newman |access-date= 28 August 2017}}</ref> Daina Bouquin, Wolbach's Head Librarian, explained that the objective is to enable full-text search of the research: "If you search for Williamina Fleming, you're not going to just find a mention of her in a publication where she wasn't the author of her work. You're going to find her work."{{Citation needed|date=August 2025}}

In July 2017, the Wolbach Library at the [[Harvard–Smithsonian Center for Astrophysics|Center for Astrophysics {{!}} Harvard & Smithsonian]] unveiled a display showcasing Fleming's work,<ref>{{cite web |url=http://altbibl.io/gazette/the-first-computer-williamina-fleming-and-the-horsehead-nebula/ |website=Galactic Gazette |title=The First Computer: Williamina Fleming and the Horsehead Nebula |author=Alex McGrath |access-date=15 September 2017 |date=3 July 2017 |archive-url=https://web.archive.org/web/20190929142207/http://altbibl.io/gazette/the-first-computer-williamina-fleming-and-the-horsehead-nebula/ |archive-date=29 September 2019 |url-status=dead }}</ref> including the log book containing the Horsehead Nebula discovery.<ref name=phaedra/> The library has dozens of volumes of Fleming's work in its PHaEDRA collection.<ref>{{cite web |url=http://oasis.lib.harvard.edu/oasis/deliver/deepLink?_collection=oasis&uniqueId=wol00001 |website=Harvard Library |title=Harvard College Observatory observations, logs, instrument readings, and calculations: an inventory |access-date=28 August 2017 |archive-url=https://web.archive.org/web/20170828233220/http://oasis.lib.harvard.edu/oasis/deliver/deepLink?_collection=oasis&uniqueId=wol00001 |archive-date=28 August 2017 |url-status=dead }}</ref>

{{As of|2017|8}}, about 200 of over 2,500 volumes had been transcribed. The task is expected to take years to complete fully. Some of the notebooks are listed via the Smithsonian Digital Volunteers Web site, which encourages volunteers to transcribe them.<ref>{{cite web |url=https://transcription.si.edu/browse?filter=owner:11 |title=Center for Astrophysics {{!}} Harvard & Smithsonian: Browse Projects |website=Smithsonian Digital Volunteers |access-date= 28 August 2017}}</ref>

==References==
{{reflist}}

==Further reading==
{{refbegin}}
*{{cite book|last1=Sobel|first1=Dava|title=The Glass Universe: How the Ladies of the Harvard Observatory Took the Measure of the Stars|date=2016|publisher=Penguin|isbn=978-0670016952}}
*{{cite book|last1=Shearer|first1=Benjamin|title=Notable women in the physical sciences : a biographical dictionary|date=1997|publisher=Greenwood Press|location=Westport, Conn. [u.a.]|isbn=978-0313293030|edition=1. publ.|url-access=registration|url=https://archive.org/details/isbn_9780313293030}}
{{refend}}

==External links==
{{Sister project links|wikt=no |commons=Category:Williamina Fleming |b=no |n=no |q=no |s=Author:Williamina Paton Stevens Fleming |v=no |species=no| voy=no |d=Q284180}}
* Waldee, S. R.; Hazen, M. L. (November 1990). ''The discovery of early photographs of the Horsehead nebula.'' Publications of the Astronomical Society of the Pacific. 102: 1337 {{bibcode|1990PASP..102.1337W}} {{doi|10.1086/132771}}
* [http://freescruz.com/~4cygni/horsehead/B33-19thC_4.htm The Horsehead Nebula in the 19th Century, by Waldee] ([https://web.archive.org/web/20150106052626/http://freescruz.com/~4cygni/horsehead/B33-19thC_4.htm archived])
* Cannon, Annie J. (November 1911). ''Williamina Paton Fleming.'' The Astrophysical Journal. 34: 314. {{Bibcode|1911ApJ....34..314C}} {{doi|10.1086/141894}}
* [https://astrosociety.org/education-outreach/resource-guides/women-in-astronomy-an-introductory-resource-guide.html Bibliography] from the [[Astronomical Society of the Pacific]]
* [http://www.projectcontinua.org/williamina-paton-fleming/ Project Continua: Biography of Williamina Paton Fleming] Project Continua is a web-based multimedia resource dedicated to the creation and preservation of women's intellectual history from the earliest surviving evidence into the 21st century.
* Birth and Marriage details from [https://www.scotlandspeople.gov.uk/ ScotlandsPeople] : Statutory Birth Record 282/02/0700; Statutory Marriage Record 282/03/0098

===Obituaries===
* {{cite journal |title=Obituary Notice : Honorary Member : Fleming, Williamina Paton |page=261 |journal=Monthly Notices of the Royal Astronomical Society |volume=72 |ref={{sfnref |Monthly Notices of the Royal Astronomical Society 1912MNRAS..72..261}} |isbn=978-1330116579 |issn=0035-8711 |oclc=1055557530 |bibcode=1912MNRAS..72..261. |year=1912 |doi=10.1093/mnras/72.4.261 |doi-access=free }}

{{Authority control}}

{{DEFAULTSORT:Fleming, Williamina}}
[[Category:1857 births]]
[[Category:1911 deaths]]
[[Category:American women astronomers]]
[[Category:Harvard Computers]]
[[Category:Harvard University staff]]
[[Category:Horsehead Nebula]]
[[Category:Scientists from Dundee]]
[[Category:Scottish astronomers]]
[[Category:Scottish emigrants to the United States]]
[[Category:19th-century Scottish women scientists]]
[[Category:20th-century Scottish women scientists]]
[[Category:Discoverers of astronomical objects]]