“Pickering’s Harem” – The Untold Story Of The Women Who Mapped Our Galaxy

In the early 20th century, Harvard – and the field of science as a whole – was dominated by men. However, one team of women provided they key to our modern conception of the galaxy, thanks to their cataloguing of tens of thousands of stars. An all-new episode of COSMOS: A Spacetime Odyssey tells the story of this groundbreaking all-female team, whose legacy has gone woefully unrecognized by history.


Beginning in 1877, Harvard astronomer Edward Charles Pickering hired a team of skilled women to process astronautical data, contributing to his mission to map the cosmos. The director of the Harvard Observatory, Pickering believed that photographs of the stars captured by the observatory held the key to understanding the universe. Strapped for manpower to examine all the observatory’s photographic data, he made a choice unprecedented in the scientific community: hiring an all-women team to analyze the results.

Disparaged by Harvard’s scientific community as “Pickering’s harem,” the team of talented women in fact performed meaningful work in mapping and categorizing types of stars, helping Pickering publish a catalogue of over 10,000 star classifications. Their work came at a time when women were fighting for equality in science and higher education when traditional systems of power still questioned their intellectual equality. In 1869, Harvard President Charles W. Eliot dismissed the idea of Harvard educating women, saying in a speech, “The world knows next to nothing about the natural mental capacities of the female sex.” In the decades that would follow, Pickering’s team would challenge Eliot’s discriminatory notions on his own turf.


Despite their important contributions to science, the team of women who worked for Pickering were still treated as lesser than their male counterparts. Pickering formed the team of women in 1881 after he fired his male assistant, who’d proven unable to keep up with the star catalogue’s demands, and replaced him with his maid, Williamina Fleming. The team’s women earned 25 to 50 cents an hour for their work, roughly half of a man’s wages at the time for similar clerical work.

Despite the low pay, long hours and tedious, repetitive tasks, the team’s work laid important scientific foundations still utilized today. Annie Jump Cannon, the leader of the team, catalogued a quarter of a million stars with the team, discovering that the stars fell into a continuous sequence according to spectral line patterns. After a bout of scarlet fever left her without hearing, Cannon went on to study at Wellesley College to pursue her childhood passion of astronomy, later transferring to Harvard’s women’s university Radcliffe College to work on Pickering’s team.


It took Cannon decades to classify the hundreds of thousands of stars according to the scheme that she devised. This system she used to distinguish these spectra from one another laid the framework for scientists’ contemporary classification of stars. Unfortunately, Cannon’s classification system does not even bear her name – it’s called the “Harvard” system instead.

Learn more about discoveries by revolutionary female scientists on tonight’s COSMOS: A Spacetime Odyssey at 9P.


  1. […] Original post: “Pickering's Harem” – The Untold Story Of The Women Who Mapped … […]

  2. Margarita
    May 7, 2014, 2:53 am

    A splendid story that needs to be told and told again. Fleming’s handwritten journal is available at Harvard library and the library will email one a PDF facsimile copy at no cost.
    This is the url http://ocp.hul.harvard.edu/ww/fleming.html
    It is very much worth reading, learning about her life bringing up her son as a single mother, doing the family laundry on her one day a week off work, and her passion for spectra.

    One thing I would note about this article is that the repetitive animated gifs are mightily and irritatingly distracting. Can they be removed? Or set so that they have to be clicked on to play.

  3. Ruth
    May 30, 2014, 11:11 am

    Thanks, Margarita for the link! I saw most of this NATGEO show and was a tad disappointed Willamina Paton Fleming wasn’t mentioned more — she’s my great, great aunt!

    Fascinating story.

  4. Melanie
    Louisville, KY
    January 12, 2015, 1:13 am

    Why are the women referred to as Pickering’s Harem? We are celebrating brilliant women in science while referring to them as a man’s sexual property, wives, or concubines. I don’t think that is appropriate. Why not refer to them as a team in the title as they are named in the article?

  5. […] “Pickering’s Harem” – The Untold Story Of The Women Who Mapped Our Galaxy | National Geographic […]

  6. Kchov
    Seattle WA
    February 26, 2016, 3:44 pm

    Those animations are from a SCI show episode.