“Harvard Computers”的意思、由来-开放百科全书

The Harvard Observatory, under the direction of Edward Charles Pickering (1877 to 1919) and, following his death in 1919, Annie Jump Cannon^[1] had a number of women working as skilled workers to process astronomical data. "The women were challenged to make sense of these patterns by devising a scheme for sorting the stars into categories. Annie Jump Cannon’s success at this activity made her famous in her own lifetime, and she produced a stellar classification system that is still in use today. Antonia Maury discerned in the spectra a way to assess the relative sizes of stars, and Henrietta Leavitt showed how the cyclic changes of certain variable stars could serve as distance markers in space."^[2] Among these women were Williamina Fleming, Annie Jump Cannon, Henrietta Swan Leavitt, Florence Cushman and Antonia Maury. Although these women started primarily as calculators, they often rose to contribute to the astronomical field, and even publish in their own names. This staff came to be known as the Harvard Computers.

History

Although Pickering believed that gathering data at astronomical observatories was not the most appropriate work, it seems that several factors contributed to his decision to hire women instead of men.^[3] Among them was the fact that men were paid much more than women, so he could employ more staff with the same budget. This was relevant in a time when the amount of astronomical data was surpassing the capacity of the Observatories to process it.^[4] Although some of Pickering's female staff were astronomy graduates, their wages were similar to those of unskilled workers. They usually earned between 25 and 50 cents per hour, more than a factory worker but less than a clerical one.^[5] In describing the dedication and efficiency with which the Harvard Computers, including Florence, undertook this effort, Edward Pickering said, "a loss of one minute in the reduction of each estimate would delay the publication of the entire work by the equivalent of the time of one assistant for two years."^[6]

The women were often tasked with measuring the brightness, position, and color of stars.^[7] The work included such tasks as classifying stars by comparing the photographs to known catalogs and reducing the photographs while accounting for things like atmospheric refraction in order to render the clearest possible image. Fleming herself described the work as “so nearly alike that there will be little to describe outside ordinary routine work of measurement, examination of photographs, and of work involved in the reduction of these observations”.^[7] At times women offered to work at the observatory for free in order to gain experience in a field that was difficult to get into.^[8]

Notable members

Mary Anna Palmer Draper

Williamina Fleming

Antonia Maury

Anna Winlock

Some of the first women who were hired to work as computers had familial connections to the Harvard Observatory’s male staff. For instance, Anna Winlock, one of the first of the Harvard Computers, was the daughter of Joseph Winlock, the third director of the observatory and Pickering’s immediate predecessor.^[11] Anna Winlock joined the observatory in 1875 to assist in supporting her family after her father's unexpected passing. Within a year, three other women joined the staff: Selina Bond, Rhoda Sauders, and a third, who was likely a relative of an assistant astronomer.^[12]

Annie Cannon

Pickering decided to hire Annie Jump Cannon, a graduate of Wellesley College, to classify the southern stars. While at Wellesley, she took astronomy courses from one of Pickering's star students, Sarah Frances Whiting.^[3] Astronomy became a big part of her life, and helped her grieve her mother's passing.^[3] She became the first female assistant to study variable stars at night.^[3] She studied the "light curve" of variable stars which could help suggest the type and causation of variation.^[3] Cannon considered merging the classification systems developed by Fleming and Maury rather than inventing a brand new one, and developed the Harvard Classification Scheme, which is the basis of the today's familiar O-B-A-F-G-K-M system. She also categorized the variable stars into tables so they could be identified and compared more easily.^[3] These systems connect the color of stars to their temperature.

Annie Cannon is one of the more famous of the computers of her group. She was the first female scientist to be recognized for many awards and titles in her field of study. She was the first woman to receive an honorary doctorate from the University of Oxford and the Henry Draper Medal from the National Academy of Sciences, and the first female officer in the American Astronomical Society. Cannon went on to establish her own Annie Jump Cannon Award for women in postdoctoral work.

Henrietta Leavitt

Henrietta Swan Leavitt arrived at the observatory in 1893. She had experience through her college studies, traveling abroad, and teaching. In academia, Leavitt excelled in mathematics courses at Cambridge.^[3] When she began working at the observatory she was tasked with measuring star brightness through photometry.^[3] She found hundreds of new variable stars after starting to analyze the Great Nebula in Orion. Her work proved successful and was expanded to study the variables of the entire sky with Annie Cannon and Evelyn Leland.^[3] With her experience in photometry, Leavitt used her skills to compare stars in different exposures. While doing this, she discovered that some stars have the same intrinsic brightness (no matter their distance from Earth). This discovery led to her developing a direct way to calculate a star's distance from earth using the period of Cepheid variable stars and their intrinsic brightness.^[13] This discovery, in turn, led to the modern understanding of the true size of the universe, and Cepheid variables are still an essential tool for the measurement of cosmological distance.

Sadly, Leavitt does not receive as much credit as she deserves. Pickering published her work with his name on it. The legacy she left allowed future scientists to make further discoveries in space. Astronomer Edwin Hubble used Leavitt's information to calculate the distance of the nearest galaxy to the earth, the Andromeda Galaxy. This led to the realization that there are even more galaxies than previously thought.

Florence Cushman

Florence Cushman (1860-1940) was an American astronomer at the Harvard College Observatory who worked on the Henry Draper Catalogue.

Florence was born in Boston, Massachusetts in 1860 and received her early education at Charlestown High School, where she graduated in 1877. In 1888, she began work at the Harvard College Observatory as an employee of Edward Pickering. Her classifications of stellar spectra contributed to Henry Draper Catalogue between 1918 and 1934.^[14] She stayed as an astronomer at the Observatory until 1937 and died in 1940 at the age of 80.^[15]

Florence Cushman worked at the Harvard College Observatory from 1918 to 1937. Over the course of her nearly fifty-year career, she employed the objective prism method to analyze, classify, and catalog the optical spectra of hundreds of thousands of stars. In the 19th century, the photographic revolution enabled more detailed analysis of the night sky than had been possible with solely eye-based observations. In order to obtain optical spectra for measurement, male astronomers at the Harvard College Observatory expose glass plates on which the astronomical images were captured at night. During the daytime, female assistants like Florence analyzed the resultant spectra by reducing values, computing magnitudes, and cataloging their findings.^[16] She is credited with determining the positions and magnitudes of the stars listed in the 1918 edition of the Henry Draper Catalogue,^[17] which featured the spectra of roughly 222,000 stars.

See also

References

1. ^{{Cite web|url=https://www.sciencefriday.com/segments/the-female-astronomers-who-captured-the-stars/|title=The Female Astronomers Who Captured the Stars|last=|first=|date=|website=|archive-url=|archive-date=|dead-url=|access-date=}}
2. ^{{Cite web|url=https://www.theatlantic.com/science/archive/2016/12/the-women-computers-who-measured-the-stars/509231/|title=The Women 'Computers' Who Revolutionized Astronomy|last=Woodman|first=Jenny|date=2016-12-02|website=The Atlantic|language=en-US|access-date=2019-03-16}}
3. ^¹²³⁴⁵⁶⁷⁸⁹¹⁰¹¹¹²¹³¹⁴¹⁵¹⁶¹⁷{{cite book|title=The Glass Universe|last=Sobel|first=Dava|date=2016|publisher=Viking|isbn=9780698148697|pages=xii}}
4. ^{{cite book|title=Women Scientists in America|last=Rossiter|first=Margaret W.|date=2006|publisher=JHU Press|isbn=978-0801857119|volume=I}}{{page needed|date=January 2017}}
5. ^{{cite book|title=Miss Leavitt's Stars|last=Johnson|first=George|date=2006|publisher=W. W. Norton|isbn=978-0393328561}} {{page needed|date=January 2017}}
6. ^{{Cite book|url=https://www.worldcat.org/oclc/972263666|title=The Glass Universe : How the Ladies of the Harvard Observatory Took the Measure of the Stars|last=Dava,|first=Sobel,|isbn=0143111345|location=New York|oclc=972263666}}
7. ^¹²Geiling, Natasha. [https://www.smithsonianmag.com/history/the-women-who-mapped-the-universe-and-still-couldnt-get-any-respect-9287444/?no-ist "The Women Who Mapped the Universe And Still Couldn’t Get Any Respect"], Smithsonian.com, 18 September 2013. Retrieved on 12 October 2017.
8. ^{{cite book|title=The Glass Universe|last=Sobel|first=Dava|date=2016|publisher=Viking|isbn=9780698148697|pages=xii}}
9. ^{{Cite journal|last=Hoffleit|first=E. Dorrit|date=2002-12-01|title=Pioneering Women in the Spectral Classification of Stars|journal=Physics in Perspective|language=en|volume=4|issue=4|pages=370–398|doi=10.1007/s000160200001|issn=1422-6944|bibcode=2002PhP.....4..370H}}
10. ^{{Cite journal|last=Nelson|first=Sue|date=2008-09-03|title=The Harvard computers|url=http://www.nature.com/articles/455036a|journal=Nature|language=En|volume=455|issue=7209|pages=36–37|doi=10.1038/455036a|pmid=18769425|bibcode=2008Natur.455...36N}}
11. ^{{cite book|title=The Glass Universe|last=Sobel|first=Dava|date=2016|publisher=Viking|isbn=9780698148697|pages=9}}
12. ^{{cite book|last1=Grier|first1=David Alan|title=When Computers Were Human|date=2008|publisher=Princeton University Press|isbn=9781400849369|page=82}}
13. ^{{cite journal|last=Leavitt|first=Henrietta S.|last2=Pickering|first2=Edward C.|year=1912|title=Periods of 25 Variable Stars in the Small Magellanic Cloud|journal=Harvard College Observatory Circular|volume=173|issue=|pages=1–3|bibcode=1912HarCi.173....1L|doi=}}
14. ^{{Cite journal|last=Spradley|first=Joseph|date=1990|title=Women in the Stars|url=https://aapt.scitation.org/doi/pdf/10.1119/1.2343078|journal=American association of physics teachers|volume=|pages=|via=}}
15. ^{{cite encyclopedia|title=Cushman, Florence|encyclopedia=Women in science : antiquity through the nineteenth century : a biographical dictionary with annotated bibliography|publisher=MIT Press|location=Cambridge, Mass.|last=Ogilvie|first=Marilyn Bailey|date=1986|edition=Reprinted|page=181|isbn=9780262650380}}
16. ^{{Cite web|url=http://altbibl.io/gazette/computersatwork/|title=Computers at Work: Astronomical labor at the HCO at the turn of the century|last=|first=|date=|website=|archive-url=|archive-date=|dead-url=|access-date=}}
17. ^Cannon, Annie J.; Pickering, Edward C. (1918) "The Henry Draper Catalogue". Annals of Harvard College Observatory.; hours 0 to 3, 91 (1918), Bibcode: 1918AnHar..91....1C; hours 4 to 6, 92 (1918), Bibcode: 1918AnHar..92....1C; hours 7 to 8, 93 (1919), Bibcode: 1919AnHar..93....1C; hours 9 to 11, 94 (1919), Bibcode: 1919AnHar..94....1C; hours 12 to 14, 95 (1920), Bibcode: 1920AnHar..95....1C; hours 15 to 16, 96 (1921), Bibcode: 1921AnHar..96....1C; hours 17 to 18, 97 (1922), Bibcode: 1922AnHar..97....1C; hours 19 to 20, 98 (1923), Bibcode: 1923AnHar..98....1C; hours 21 to 23, 99 (1924), Bibcode: 1924AnHar..99....1C.