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
Written by Elizabeth Coquillette, 2022
Anna Winlock used a few terms to describe her profession on city and federal documents. On the 1880 Federal Census, and on City Directories between 1881 and 1896, She uses “Asst. at Observatory” (Assistant). On the 1900 Federal Census, and on her death certificate, “Computer” is listed.
For questions on any particular Women Astronomical Computer’s titles please consult their bio page. If no terminology information is listed, feel free to email us!
Selected Publications:
Rogers, William A. and Anna Winlock. “A Catalogue of 130 Polar Stars for the Epoch of 1875 Resulting from All the Available Observations Made between 1860 and 1885 and Reduced to the System of the Catalogue of Publication 14 of the Astronomische Gesellschaft.” Memoirs of the American Academy of Arts and Science no. 2 (1886): 227-299. doi: 10.2307/25058053
Rogers, William A., Anna Winlock, and Edward C. Pickering. “Journal of the zone observations of stars between 49d 50’ and 55d 10’ of north declination in 1855.0 and observed with the meridian circle during the years 1875 to 1885.” Annals of Harvard College Observatory vol. 36 (1896): 1-299.
Winlock, Anna. Absolute Work: Meridian Circle Obs. 1879-1881. 1879. [1879phae.proj..438W] Cambridge, MA: John G. Wolbach Library, Harvard College Observatory. Project PHaEDRA. Harvard College Observatory observations, logs, instrument readings, and calculations. Transcript (accessed May 19, 2022).
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↩