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Pickering’s Harem.

Harvard College Observatory was founded in 1839 at a time when universities were beginning to receive funds for astronomical research, which previously was the province of learned men with plenty of spare time and independent means to indulge their passion. Astronomy is a science requiring observations and rigorous calculations, particularly of the position of celestial objects. This was tedious work that was undertaken by “computers”, which were at that time young men, generally just out of college or university. The RGO had a number of young men carrying out this task right into the early 1900’s.

At Harvard observatory, this changed when Edward Pickering became director of the observatory in 1877. He realized that with the new technologies coming on line at the time, better telescopes with astrophotography developing and the data collecting happening faster than could be handed and catalogued so that it could be useful to science. This of course is happening now, with scientists having to devise new citizen programmes to collate and scan the collected data.

At this time Harvard College Observatory was about to be asked to complete a task of truly astronomical proportions.

One gentleman of independent means was Henry Draper (1837-1882) who was a physician, an amateur astronomer and a pioneer of astrophotography. He acquired his interest in astronomy from his father who took the first ever image of the Moon back in 1839.

Henry Draper also had a number of firsts in his life. First ever photo of the Orion Nebula, 1880, and the first photo of a spectrum of a star, Vega, 1872. He also invented the now familiar slit spectrograph. His major observing project was to photograph the entire sky and to create a complete spectral catalogue which would then be available to others for research. Unfortunately, he was not able to complete the project due to his untimely early death at the age of 45. However, his wife was determined to see that his dream was to come true, she donated a huge sum of money to Harvard College Observatory to complete this monumental task in honour of her husband.

 By happy coincidence, at this time Pickering had been hiring a number of women to undertake the cataloguing and computing work at the observatory, how this came about seems to be, as legion has it, Pickering was becoming increasingly dissatisfied with his male assistants, and in a huff one day shouted out that his housemaid could do a better job. Needless to say that he probable also had in mind that he would able to double his computing staff as women were paid less than half the salary of the male workers, earning between 25 and 50 cents an hour. As it happened, Pickering was to find that the ladies were to do a better job that the men and a few were to become high flyers in the astronomical world. Although the women computers at Harvard became known by the unflattering name of “Pickering’s Harem” it is not recorded what the women themselves thought of the name. As an aside, it is interesting that the word Harem is derived from the Arabic word “Harem” which means “prohibited place”. As Pickering was allowing women into the prohibited place of an all-male observatory, the name was rather appropriate.

The first woman hired was Williamina Flemimg who at the time was working for Pickering as his housemaid. She was born in Dundee, Scotland in 1857, to Mary and Robert Stevens, she was educated in several public schools and became a student teacher at the age of 14. In 1877 she married James Flemming and immigrated to America setting up home in Boston. A few months later she was pregnant and James Fleming promptly abandoned her, the cad. So living in a strange country and in need of money to support herself she found employment as a housemaid to Professor Edward Pickering, the director of Harvard observatory. Not long after she was offered the part time position at the observatory as a part time copyist and computer. Pickering obviously recognised her as an intelligent and educated lady.

She became a permanent member on the observatory staff. It was soon after this that the Harvard Observatory received the funding mentioned earlier from Mrs Anna Draper to complete her husband’s catalogue. Work started on the Henry Draper catalogue, and Fleming eventually found herself responsible for indexing, examining and taking care of the new photographic plates. These plates were taken by placing a prism in front of the object glass of the telescope, a system that produced stars as spectra. The computers were put to work identifying the stars on the plates, calculating their positions and classifying the spectra. It took twelve years for Fleming’s to be recognised by the College authorities as a full assistant becoming the first woman to have the title of Curator of Astronomical photographs bestowed on her.

Not only was Fleming now responsible for employing and supervising new members of staff, she also organised the storage and classification of the objects on the plates so that they could be easily found and the data quickly past to whoever needed it. She devised her own system of dividing the stellar spectra into classes using the capital letters A to Q, omitting I, J and P. (why?) based mostly on the strength of the Hydrogen lines.

Fleming worked at the observatory till her death at the age of 54 in 1911. During this time, she discovered 10 novae, 59 gaseous nebulae, 94 Wolf-Rayet stars (large, very bright stars nearing the end of the helium burning stage of their cycle) and over 200 long period variables. She also received many honours and awards for her contribution to astronomy, including honorary membership to our own Royal Astronomical Association.

The second high flyer Antonia Maury, born in 1866, her father was a church minister and her mother just happened to be the sister of Henry Draper. She gained her astronomical knowledge while at Vassar College (the first all women college) in 1887 and was a student of Maria Mitchell. Due to the endowment to Harvard Observatory for the Henry Draper Catalogue project by her aunt Anna Drapper, Maury was hired by Pickering as a computer in 1888. (Was this part of the deal? Who knows?)  She worked on the cataloguing and computing stellar spectra in the northern hemisphere. However, she was not interested in just performing routine calculations she wanted to do theoretical work; this created strained relations between her and Pickering which coursed her intermittently parting company with the observatory then reappearing again sometime later to carry on as if nothing had happened. Maury rearranged Fleming’s Spectra cataloguing scheme to reflect the temperatures of the stars, by adding extra subscripts like a lower case “a” for well-defined spectra, lower case “b” for less well defined hazy spectra and a lower case “c” for spectra were the H lines and the Helium lines were sharply defined. (The Helium lines were known at that time as “the Orion lines”).

Maury firmly believed in her category scheme, but Pickering, the observatory's director, disagreed with her system of classifications and the explanation for the differing line widths. This created another one of the many riffs between her and Pickering. The work was eventually published with her classification. Her most famous work done at the observatory was the spectroscopic analysis of the binary star Beta  Lyrae, published in 1933.She officially retired from the observatory in 1935, after which she carried on various freelance work, but still occasionally returning to update herself on the latest observations regarding her project involving Beta Lyrae. Antonia Maury died in 1952, but she had many honours and recognitions bestowed on her by fellow astronomers worldwide, including a crater on the Moon.

Henrietta Swan Leavitt was born in 1868, she was educated at various schools and Colleges, finally graduating from what is now known as the Radcliff College. Taking a few gap years she travelled across America and Europe during which time she lost her hearing. After her travels she gained a post as assistant at Harvard College Observatory.

Within a short time she was given the position of Chief of the photographic photometry department where she was able to undertake research work from the observatory’s photographic plate collection determining stellar magnitudes. As there was no standard for making magnitude estimates at that time she devised her own system, using the North Polar Sequence of Stars, which was quickly recognized by the astronomical world as an important standard and was officially adopted by the International Committee for Photographic Magnitudes in 1913. Leavitt’s main research area was the variable stars in the Small Magellanic Cloud. As all the stars in the SMC can be taken as being at the same distance from us, Leavitt was able to determine the absolute magnitudes of the stars in the cloud, which lead to the development of the Period-Luminosity relationship between the period of a Cepheid variable star and tis mean brightness. This gave astronomers a tool to work out the distances to other objects. Hertsprung used the relationship to plot distances of stars, Harlow Shapley used it to measure the distances to the globular clusters and so measured the size of the Milky Way, while Edwin Hubble was able to use it to measure the age and expansion of the Universe. Quite a monumental contribution to the advancement of astronomy for just one person and indeed makes one wonder what else she could have achieved if she did not died at the young age of 53  in 1921.

The next high flyer, Annie Cannon is perhaps the star in the crown of all the members of the Harem. Born in 1863 she became enthralled with astronomy while her mother taught her the constellations as a young girl. She studied physics at College, graduating in 1884. She lost interest in astronomy and for the next eleven years she studied music and went travelling during which time she lost her hearing. It seems to have been a dangerous time for travelling as you may remember; Henrietta Leavitt also lost her hearing while travelling around the same time.

After the death of her mother she decided to pursue astronomy and attended Radcliffe College as a special student for a couple of years. Apparently, it was Pickering who got her this special status, I have not been able to find out why, but did she apply to Pickering for a post at the observatory and Pickering packed her off the college to learn the trade? However, in 1896 she joined the ranks of the computers at HCO. One year after Leavitt joined. It must have been interesting working in the same room as two very intelligent deaf women absorbed in their own studies. Cannon catalogued variable stars and classified the spectra of stars in the southern hemisphere for the Henry Draper project, working in conjunction to Antonia Maury’s northern hemisphere work. She was able, probably due to her deafness, to work at an incredible speed and accuracy, and it is said that in her lifetime she classified 350,000 spectra at a rate of 300 an hour.

Cannon altered the cataloguing schemes of both Fleming, who by this time had been promoted to Curator of Astronomical Photographs, and Maury. With the Fleming scheme, you may remember that she used the letter A to Q, omitting the letters I, J and P. Cannon reduced these down to seven, O B A F G K and M. Then going to work on Antonia Maury’s system of lower case letters for the sub categories, Cannon used the numbers 1 to 10, a system which, with a few minor differences, is in use today. Annie Cannon work at the observatory for 45 years until the end of her life in 1941. Annie also took part in some expeditions away from the observatory, for instance, in 1925 she was stationed at Poughkeepie (pa-KIP-see) in the Hudson Valley for the total eclipse of the Sun. She also revised the Henry Draper Catalogue twice, published several books. She was given an honorary degree from Oxford University, one of six honorary degrees awarded to her. With one award, the Ellen Richards Research prize, she was able to establish an independent award called the Annie Jump Cannon Award in Astronomy to recognise contributions by women to astronomy. This award to Annie must have been quite substantial as the value of the award is now is $1500 each year. It is interesting to note that Antonia Maury was a recipient of the award in 1943.

These four ladies are the stars of the show, but there were many others who work alongside them, not much is known of them except what little appears in reports and the annals of the observatory published at the time.

One fine reference that helps bring these other workers to life is the book “The History and Work of Harvard Observatory” by Salon Bailey which was published in 1931. I found a list of staff members with a lot of names in it, so I have chosen to have a quick look at a few of the harem that we have in photographic form.

First Florence Cushman, who joined the staff in 1888, she worked for many years on the reductions of observations and the preparation for publication of the photometric observations.

Then there is Evelyn Leland who helped with the variable star work being done by Annie Cannon and Henrietta Leavitt. Their method of finding variable stars is interesting. By laying a negative plate over a positive plate taken on a different date they were able to see at a glance any variable stars in that region of the sky. Looking at the various photos of the ladies, it seems to me that others were also involved in this work, including

Arville Walker who did the astrometric work in determining the positions of the stars while leavitt made the magnitude estimates and Cannon classified the spectra. Arville Walker later became secretary to Harlow Shapley when he took over the Directorship of the observatory on the death of Pickering.

Two others certainly need mention, Johanna Mackie and Ida Woods who worked together during 1919 to 1921 on a systematic photographic search of the Milky Way for Novae, discovering 8 new novae and finding 6 more that were already known.

Margaret Harwood came from the Maria Mitchell observatory at Nuntucket where she was the director. During 1912 she and Pickering work on the proper motions of stars using data collected photographically at Harvard.  So I suppose she was not really one of the Harem although she is listed as a staff member in the list I showed earlier.

In 1914 she made some observation of the asteroid Eros and combining these observations with those made at Harvard she was able to calculate the rotation of Eros to 0.3064 days (7hrs 21 mins)


I think that it is true that Professor Edward Pickering did a great service to astronomy by introducing women into the observatory environment as is shown by the number of excellent and expert female astronomers that have since worked, and are now working in observatories all over the world.