Williamina Fleming: Star of Scotland

This extract is a chapter from the women in STEM anthology, A Passion For Science: Tales of Discovery and Invention.

by Sue Nelson

In 1879 Williamina Paton Stevens Fleming found herself pregnant, unexpectedly alone and far from home. The year before, together with her husband James, she had emigrated from Scotland to the United States. Abandoned in Boston at the age of 23, after just two years of marriage, she faced the prospect of being a single parent in a strange country, with no money and nowhere to live.

It was both an exciting and dangerous time to be in America. Only a few years earlier the Sioux nation had defeated Lt Colonel Custer at the Battle of Little Bighorn. In Deadwood, a travelling buffalo hunter had shot Wild Bill Hickock in the head while playing poker. The Brooklyn Bridge and the Washington Monument were merely works in progress and it would be another 18 years before Boston had its own subway.

There were only 38 states in this relatively new country, but 1879 was special. In a world of dim gaslights, Thomas Edison had invented the first functioning light bulb and, in the same year, Williamina Fleming took her first steps towards shining her own light on the world of astronomy.

Within thirty years of what can only be described as an inauspicious start, Fleming had catalogued over 10,000 stars and had discovered 310 variable stars, 10 novae, 52 nebulae and the hot dense stars known as white dwarfs. Long after her death, when the Hubble Space Telescope unveiled the stunningly beautiful Horsehead Nebula in unprecedented detail, history had already noted that it was Williamina Fleming who had first identified the nebula’s unusual shape.

The Scotch maid

But all that was yet to come. In 1879, when she was probably at her lowest ebb, Fleming applied for a job as a maid and housekeeper at the Harvard College Observatory. As a former schoolteacher from Dundee, this must have been a difficult adjustment, despite the fact that Fleming was one of nine children and had been teaching since the age of 14, while still a pupil, to contribute to the family income. Whether a natural survivor or not, this simple act of necessity was life changing.

The director of the observatory, Edward Pickering, was a professor of astronomy who employed low-paid ‘computers’, primarily men, who examined photographic plates. These plates, each about the size of an old 78 RPM record sleeve, contained images of stars taken from telescopes in Harvard and the southern hemisphere. They appeared as hundreds of fine grey or black spots on transparent glass. On the spectral plates, where starlight had first been split by a prism, the images resemble smudged pencil marks.

The computers examined the captured starlight with magnifying glasses to catalogue the stars’ brightness as well as calculating, or ‘computing’, their positions. In the case of spectral plates, information such as chemical composition, colour and temperature of the stars could be gleaned from each millimetre long spectrographic barcode of information.

At first glance it appears as if Pickering wasn’t overly impressed by what computers did — he apparently declared the work so easy that even his “Scotch maid” could do it. Women were paid less than men at that time, so there was admittedly a financial gain in employing women over men. But I suspect that this disingenuous remark reveals that he knew his intelligent “Scotch maid” was more than a match for his male computers. Why else would he promote his housekeeper to a full-time Harvard Observatory staff member within two years?

Fleming was soon put in charge of hiring the computers and, as she recruited more women, Pickering’s harem took shape. It contained women, like Fleming, with no formal astronomical training who were not expected to think but nevertheless applied intelligence and insight to their work.

Computing was repetitive, painstaking and paid little — even the factory girls at the nearby Lowell mill were paid more — but it offered mental stimulation to those who applied and used their own minds. Women also began arriving at the Harvard Observatory from fledgling women’s colleges. These women were more educated and keen to observe, classify and research the heavens, searching for patterns within the data.

By 1890, a photograph of the computers at work reveals a Victorian-style drawing room filled with women in long dresses, high-necked shirts and long hair coiled upon their heads. Fleming stands upright at the back, petite with dark hair and a tight waist-fitting jacket. Her mentor, Edward Pickering, is in the corner of the room. He may be in charge but it is obvious that the women in the room are her domain.

There are books, mahogany tables, flowered wallpaper and framed pictures on the wall. Several of the women computers look as if they are doing embroidery but on closer inspection these ‘samplers’ are photographic plates. These women are not sewing. They are stargazing.

The Horsehead Nebula

A million or so of these glass plates are still stored at Harvard in brown cardboard sleeves. One of them was taken by Pickering and is numbered B2312. It was on this that, two years after it was taken, Fleming discovered the Horsehead nebula. She described it as “a semicircular indentation 5 minutes in diameter 30 minutes south of Zeta (Orionis).”

Fleming rewarded Pickering’s faith in her intelligence and ability. She established the first photographic standards of magnitude — an important tool for astronomers — that were then used to measure the brightness of variable stars, whose light fluctuated. She also developed a new Pickering-Fleming system to classify stars by their spectra alphabetically, A, B, C and so on, according to the strength of the star’s hydrogen spectral line.

Within a decade she had studied and classified over 10,000 stars — most of those visible to the naked eye — for the Draper Catalogue of Stellar Spectra (1890). The catalogue was funded by Anna Draper, in memory of her late husband Henry Draper, a doctor and amateur astronomer from New York who pioneered the use of photography in astronomy.

Anna established the Henry Draper Memorial to support photographic research and it resulted in the catalogue, which is still in use today. Although Pickering did not name Fleming as co-author, he did credit her work in the book, and she was recognised for her contribution within the astronomical community.

At first Fleming was also uncredited for the Horsehead nebula, as a result of the star index catalogue’s compiler only naming Pickering, but this was amended by the second version years later. Pickering also encouraged the women computers to attend conferences and present papers, allowing them to flourish professionally.

In fact, Pickering’s forward thinking with regard to his women computers must have been anathema to his contemporaries. Much later, in 1901, the director of Yale Observatory, William Elkin, said: “I am thoroughly in favour of employing women as measurers and computers. Not only are women available at smaller salaries than are men, but for routine work they have important advantages. Men are more likely to grow impatient after the novelty of the work has worn off and would be harder to retain for that reason.”

Elkin couldn’t have been more wrong. The novelty for many never did wear off. The computers Fleming hired included Antonia Maury, Henrietta Swan Leavitt and Annie Jump Cannon, all astronomers who each made significant contributions to the field.

Jump Cannon recorded the spectral classification of 300,000 stars. Unlike Fleming, Jump Cannon had studied physics and astronomy both as an undergraduate and graduate at the all-women Wellesley College. She also upgraded and simplified the Pickering-Fleming system of classification from the bluest hottest stars to the coolest red ones.

As a result, the previous alphabetical order had to be rearranged to O, B, A, F, G, K, M. This order is recalled by students even today with the mnemonic Oh Be A Fine Girl and Kiss Me.

The International Astronomical Union eventually adopted this system in 1922 as the definitive way to classify stellar spectra — all made possible by building upon the work by Pickering and Fleming.

Dedicated to the stars

In 1898 Fleming became the first woman curator of the Observatory’s astronomical photographs. Some of the pages from her journal written in 1900 reveal the range of her work. “Before lunch I found time to examine a few southern spectrum plates and marked a fourth type star and a gaseous nebula, both probably known. Later it the afternoon I noted a few more interesting objects, among these two fourth type stars, one gaseous nebula, and several bright line stars. Some of these may be new.”

The entries also give an insight into her dedication and the sheer workload. “Looking after the numerous pieces of routine work which have to be kept progressing, searching for confirmation of objects discovered elsewhere, attending to scientific correspondence, getting material in form for publication, etc, has consumed so much of my time during the past four years that little is left for the particular investigations in which I am especially interested,” she wrote.

“The Director, however, says that my time employed in the above work is of more value to the Observatory so I have delegated my measures of variables etc to Miss Leland and Miss Breslin. I hope, however, to be able soon to finish the measures of the out of focus plates and to get well settled down to my general classification of faint spectra for the new Draper catalogue.”

There is a lot more to learn about Fleming. She returned to Scotland to give birth to her son but came back to continue working at the Observatory, leaving her son with her mother and grandmother. She named her son Edward Charles Pickering Fleming — which could be seen as a simple act of gratitude or possibly reflects that her relationship with the Observatory director was more than employer-employee. There has also been speculation that maybe this was the reason her marriage broke up.

By 1907 Fleming had been appointed an honorary fellow in astronomy at Jump Cannon’s alma mater and was the first American woman to be elected an honorary member of London’s Royal Astronomical Society. In 1910, Fleming published her discovery of stars that have almost exhausted their nuclear fuel. These small stars have expelled their outer layers, creating a planetary nebula and leaving an extremely dense hot core. They were called white dwarfs because the first few discovered were white.

Fleming died in Boston of pneumonia, aged 54, on the 21st May, 1911. Her life had been a tremendous and unique journey. Fleming left Dundee as a young woman and schoolteacher, survived a broken marriage and, at a time when a woman’s place was in the home, departed the world thousands of miles away as an astronomer at Harvard Observatory.

It was a transformation from a housekeeper and maid to being the discoverer of white dwarfs and the recipient of the Astronomical Society of Mexico’s Guadalupe Almendaro medal for her discovery of new stars.

Fleming’s life was also a personal journey for me. In 2002, during a sabbatical from being a BBC science correspondent, I was studying space science as part of a Knight-Ridder journalism fellowship at the University of Michigan. During an astronomy 101 lecture there, a fleeting mention was made of the Harvard Computers and stellar spectral classification. As soon as I heard about these women, I couldn’t concentrate for the rest of the lecture. I had to find out more about them.

Two years later it resulted in a Radio 4 programme called The Harvard Computers and a short article in The Times. I got to see these astronomical plates for myself, as well as the Observatory where Fleming and her computers used to work.

Today I remain intrigued and proud of these women’s achievements and of Fleming in particular. After publishing a popular science book the same year as the radio programme, I tried to sell a book on her life but was told ‘no one buys science history any more’. So if anyone reading this thinks otherwise, contact me immediately. Because I for one cannot forget the woman and astronomer called Williamina Fleming. She was the star of Scotland.

About the author

Sue Nelson is an award winning science writer and broadcaster. She makes podcasts, short films and BBC Radio 4 science programmes through Boffin Media and is a former BBC science correspondent.

Twitter: @sciencenelson and @spaceboffins