Born: 15 September 1857, United States
Died: 4 Janaury 1904
Country most active: United States
Also known as: NA
The following bio was written by Emma Rosen, author of On This Day She Made History: 366 Days With Women Who Shaped the World and This Day In Human Ingenuity & Discovery: 366 Days of Scientific Milestones with Women in the Spotlight, and has been republished with permission.
Anna Winlock was a distinguished American astronomer and a notable member of the pioneering female computer group known as “the Harvard Computers.” Her significant achievements include creating a comprehensive star catalog of the polar regions and making substantial contributions to asteroid research, particularly regarding 433 Eros and 475 Ocllo.
Following her father’s passing, Winlock sought employment at the Harvard College Observatory to support her mother and four siblings. She specialized in the reduction of extensive, previously unprocessed astronomical observations left incomplete by her father. Despite initial financial constraints, she accepted a position at the observatory for twenty-five cents per hour, demonstrating her dedication to astronomical computations.
Within a year, Winlock was joined by three other women at the observatory, collectively known as “Pickering’s Harem.” Despite their remarkable contributions and the quality of their work, they faced criticism for low wages and demanding tasks. Winlock’s commitment to advancing women in astronomy remained steadfast, setting an example of equal capability between genders.
Throughout her thirty-year tenure at the Harvard College Observatory, Winlock engaged in various projects. Her most significant undertaking involved the reduction and computation of meridian circle observations, particularly within the “Cambridge Zone” of a global star catalog project initiated by her father. Over two decades, her team’s work significantly contributed to the Astronomische Gesellschaft Katalog, a valuable resource for numerous observatories worldwide. Additionally, Winlock supervised the creation of the Observatory Annals, a compilation of tables providing variable star positions in clusters, spanning 38 volumes.
This biography of Anna Winlock was sourced from the Harvard Plate Stacks website on January 14, 2024. It was written by Elizabeth Coquillette, Curatorial Assistant at the Harvard Plate Stacks, in 2022. Please note that this information may have been updated since it was added to our database; for the most current information, check their website at https://platestacks.cfa.harvard.edu.
Anna Winlock (1857-1904) was the one of the first paid female staff member of the Harvard College Observatory, and she worked at the Observatory for 28 years from 1875-1903. She is best known for her extensive computation work with meridian circle observations and asteroid orbits.
Winlock dedicated her first 21 years at the observatory to working with observations from the meridian circle instrument that had been installed in 1870 by her father Joseph Winlock, then the director of the HCO.1 Harvard had joined with several foreign observatories on a project to prepare a comprehensive star catalog for the northern sky from the first to ninth magnitudes, and Miss Winlock performed a large portion of the calculations for the Cambridge zone of the project.2 The results were published in phases between 1891-1896, and Winlock’s dedication to the project allowed Harvard to be one of the first of the collaborating observatories to publish its portion of the project.3
After completing the meridian circle project, Winlock went on to assist Williamina Fleming, the leader of the women computers, with her work on the asteroid Eros, the first near-Earth object ever discovered.4 Eros has attracted significant scientific attention from its discovery in 1898 to the present day, including becoming in 2001 the first asteroid ever landed on by a spacecraft.5 Fleming, Winlock, and other HCO women provided important early computations about its orbit and predicted future movements.6
Winlock gained substantial media attention in 1901 when she and Dr. Simon Newcom published their joint work computing the path and elliptical elements of a newly discovered asteroid, Ocllo, finding that it had the least circular orbit of any asteroid yet known.7 The inclusion of a woman astronomer in the Ocllo announcement prompted newspaper articles throughout the country that discussed the importance of women’s contributions to astronomy in the past and present.8
Winlock was the daughter of Joseph Winlock, who was the third director of the Harvard College Observatory from 1866-1875, and Mary Isabella Lane Winlock. As a child, Winlock was very interested in her father’s work, and at the age of 12, she accompanied him on an expedition to Kentucky to see the 1869 solar eclipse.9 She graduated from high school at around the same time as her father’s sudden death in June 1875, and she joined the HCO shortly after.10 Anna was the eldest of the Winlock family’s six children, and her younger sister Louisa followed in her footsteps and began working at the observatory in 1886.11 While at the HCO, Winlock was viewed among both her male and female colleagues as patient, devoted, unpretentious, and uniquely talented in mathematics.12 After her death in 1904, she was interred in the Winlock family plot at the Mount Auburn Cemetery in Cambridge, MA.13
Works cited
1-Mary E. Byrd, “Anna Winlock,” Popular Astronomy (1904): 256.
2-Marilyn Ogilvie and Joy Harvey, The Biographical Dictionary of Women in Science: Pioneering Lives From Ancient Times to the Mid-20th Century (London: Routledge, 2000), 1389.
3- Byrd, “Anna Winlock,” 256.
4-Solon I. Bailey, The History and Work of Harvard Observatory, 1839 to 1927; an outline of the origin, development, and researches of the Astronomical observatory of Harvard College together with brief biographies of its leading members (New York: McGraw-Hill, 1931), 111.
5-“Asteroids > 433 Eros,” NASA Science: Solar System Exploration, June 29, 2021; James Falese and David Sliski,“Asteroid 433 Eros, Part 3.” Galactic Gazette blog, Center for Astrophysics: Harvard & Smithsonian, October 20, 2013.
6-Paul Murdin, Rock Legends: The Asteroids and Their Discoverers (New York: Springer, 2016).
7-“The New Asteroid: Elliptical Elements Computed From Photograph Taken in Peru Last Summer,” New York Times, Nov. 16, 1901; “Camera Reveals New Asteroid: Phenomena of Solar Satellite Recently Photographed at Arequipa,” The Washington Post, Nov. 16, 1901; “Her Camera Caught Asteroid: Woman Astronomer Offers a Surprise to Scientists Which Interests Them,” Brooklyn Daily Eagle, Nov. 15, 1901.
8-“Disciples of Hypatia: Women Engage in Astronomical Pursuits: America Has Many Who Observe, Classify, and Compute,” New York Tribune, Nov. 24, 1901; “Women and Stars: Many of the Fair Sex Skilled in Observations,” The Topeka Daily Herald, Jan. 8, 1902; “Women As Astronomers,” The Nashville American, Dec. 22, 1901; “Women Engaged in Astronomy: Good Work Done By Them Home and Abroad: Progress in the Science,” The Washington Times, Dec. 1, 1901.
9-Byrd, “Anna Winlock,” 255.
10-Ogilvie and Harvey, The Biographical Dictionary of Women in Science, 1388.
11- “Anna Winlock (1857-1904),” Find A Grave, accessed May 19, 2022; Paul A. Haley, “Williamina Fleming and the Harvard College Observatory.” The Antiquarian Astronomer: Journal of the Society for the History of Astronomy, no. 17 (June 2017): 7.
12- Byrd, “Anna Winlock,” 257-258; “Disciples of Hypatia.”
13-“Anna Winlock (1857-1904),” Find A Grave