Thursday, January 29, 2015

Women “Computers” Explored the Cosmos – Part 7

As we continue to learn about Henrietta’s research, we see she produced numerous advances in the field. Henrietta discovered a means to not only identify, but rank the magnitudes of stars using photographic plates. Henrietta discovered a way by which astronomers became better able to accurately measure extra galactic distances known as the period-luminosity relation. She also discovered more variable stars than any other astronomer of her time.

Pickering soon promoted Henrietta to department head of the photographic photometry (science of measuring the brightness of stars). In 1912, Henrietta, by comparing different photographs of the same variable star, especially those stars of the “Cepheid” type that had bright-dim cycle periods, established that the slower the blink time the more light or brightness the star contained.

The Cepheid research excited Henrietta, but Pickering hired her to do a specific job, and would not allow her or the other “computers” to veer from their assigned tasks. Cecilia Payne-Gaposchkin, who never knew Leavitt, felt that by not giving Henrietta full rein to explore her passion for variable stars, “condemned a brilliant scientist to uncongenial work, and probably set back the study of variable stars for several decades.”1

“…it ruthlessly relegated Miss Leavitt to the drudgery of fundamental photometry when her real interest lay in the variable stars that she had begun to discover in the Magellanic Clouds.”2

"What a variable-star 'fiend' Miss Leavitt is," wrote Charles Young of Princeton in a letter to Pickering. "One can't keep up with the roll of the new discoveries."3

One of Henrietta’s discoveries concerned the redness of stars. She found that fainter stars were usually redder than brighter ones. This led her to question “whether the light was possibly reddened by interstellar absorption.”4

1George Johnson. Miss Leavitt’s Stars: The Untold Story of the Woman Who Discovered How to Measure the Universe. (New York: W. W. Norton & Co., 2005), 91.
2Cecilia Payne-Gaposchkin. Cecilia Payne-Gaposchkin: an Autobiography and other Recollections. (Great Britain: Cambridge University Press, 1984), 145.

4Harry G. Lang, Bonnie Meath-Lang. Deaf Persons in the Arts and Sciences: A Biographical Dictionary. (Westport, Connecticut: Greenwood Press, 1995), 221.

Thursday, January 22, 2015

Women “Computers” Explored the Cosmos – Part 6

(NOTE: You will note that this series of blogs on female astronomers are heavily cited. I have two reasons for giving the reader these citations. 1) I am not a scientist and I often use the words of others to be sure I am giving correct information. 2) I am hoping some readers will have enough interest to go to these cites and find additional information.)

As we continue learning about Henrietta Swan Leavitt, I want to challenge the oft-cited information that she was profoundly deaf. Although it is in almost all sources referring to Henrietta, it is not proven by any citation. The claim is that she became profoundly deaf from an illness she suffered right after her graduation.  There is no evidence of that because she could still hear when she took the position with Pickering. “My friends say, and I recognize the truth of it, that my hearing is not nearly as good when absorbed in astronomical work,” Henrietta wrote to Edward Pickering in a letter.1 It is more likely she lost her hearing progressively during her career.

“She worked diligently away at her job, even as her hearing slowly failed and her health began to suffer.” 2

Since both Henrietta and Annie Jump Cannon suffered illnesses right after graduating college, it is possible she has been confused with Annie, who did lose her hearing from a bout with scarlet fever.
At the time Henrietta began, there was no standard for determining magnitudes. “Leavitt devised a system, using ‘the north polar sequence’ as a gage of brightness for stars during her investigations.”3

Henrietta’s discovery of the period-luminosity during her study of the Cepheid variables in the Magellanic Clouds proved “The longer the time required for the star to go from maximum brightness through its faintest phase back to maximum again, the brighter the star is.”4

The scientific community recognized and adopted this new system as an important standard. In 1913, the International Committee on Photographic Magnitudes adopted Henrietta’s system.

More Monday about Henrietta and the milestones she left behind in the annals of astronomy.

1George Johnson. Miss Leavitt’s Stars: The Untold Story of the Woman Who Discovered How to Measure the Universe. (New York: W. W. Norton & Co., 2005), 31.
2 (Accessed January 20, 2015)
3 (accessed January 20, 2015).

4James Pickering, 1001 Questions Answered about Astronomy. (Guildford and London: Lutterworth Press, 1958), 173, 175.

Monday, January 19, 2015

Women “Computers” Explored the Cosmos – Part 5

Annie Cannon, an astronomer we will hear more about in upcoming blogs, said of Mina, “Industrious by nature, she was seldom idle, and long years of observatory work never unfitted her for the domestic side of life. As much at home with the needle as with the magnifying eyepiece, she could make a dainty bag, exquisitely sewed, or dress a doll in complete Scotch Highland costume. She was never too tired to welcome her friends at her home or at the observatory, with that quality of human sympathy, which is sometimes lacking among women engaged in scientific pursuits. Her bright face, her attractive manner, and her cheery greeting with its charming Scotch accent, will long be remembered by even the most casual visitors to the Harvard College Observatory.”1

Of course, Mina’s most important work published was the Draper Catalogue of Stellar Spectra in 1890, but she also published A Photographic Study of Variable Stars in 1907, Spectra and Photographic Magnitudes of Stars in Standard Regions in 1911, and Stars Having Peculiar Spectra was published in the Annals of Harvard College Observatory in 1912, after her death.2

In 1906, Mina became the first American woman elected to the Royal Astronomical Society in London. Soon after, she was appointed honorary fellow in astronomy of Wellesley College. Shortly before her death, The Astronomical Society of Mexico awarded her the Guadalupe Almendaro medal for her discovery of new stars. Mina died of pneumonia on May 21, 1911, still doing the work she loved.

Even though, a non-astronomical minded person (such as myself) might not understand the importance of these discoveries, it is quite evident Mina should be honored for being one of the first in her field and paving the way for other women.

Nearby, in her senior year at the Society for the Collegiate Instruction for Women, (which later became Radcliffe College), Henrietta Swan Leavitt became interested in astronomy. Health problems kept her from joining Pickering’s crew for some time after graduation but finally in 1893, when she was 25 years old, she arrived at the observatory as a volunteer wanting to learn more about astronomy. Her knowledge thus far had been classes she took after graduation before she became ill.

In 1902, Pickering hired Henrietta to be one of his “computers.” The job paid $10.50 a week. The environment at the observatory was cold and damp, not the best place for someone who already had health problems.

1Annie J. Cannon, “Minor Contributions and Notes. Williamina Paton Fleming,” The Astrophysical Journal, Vol. 34 (July 1911), 314-317.

2 (accessed December, 29, 2014).

Thursday, January 15, 2015

Women “Computers” Explored the Cosmos – Part 4

In her journal on March 12, 1900, Mina chafed against the inequalities at the observatory. “He seems to think no work is too much or too hard for me no matter what the responsibility or how long the hours. But let me raise the question of salary and I am immediately told that I receive an excellent salary as women’s salaries stand.”1

Actually, no one at the observatory made very much money. I have not been able to find a salary figure for the period in 1900 that Mina is journaling about but I feel sure it would have risen in her twenty-year experience from the $10.50 a week she earned as a starting “computer,” in 1881. Even Pickering, who worked very long hours, only made sixty-five dollars a week.

Mina, like women before and after, struggled with equating compensation with quality of work. On April 18, 1900, her journal entry regarding her March 12th comments: “I do not intend this to reflect on the Director’s judgment, but feel that it is due to his lack of knowledge regarding the salaries received by women in responsible positions elsewhere. I am told that my services are very valuable to the Observatory but when I compare the compensation with that received by women elsewhere I feel that my work cannot be of much account.”2

Even though, Mina could get very frustrated with Pickering, from the very beginning, she admired him immensely. She even named her only son Edward Pickering Fleming.3

As with the other human “computers,” Mina in her diary expressed impatience with not being able to do the exact work she loved. “If one could only go on and on with original work, looking to new stars, variables, classifying spectra and studying their peculiarities and changes, life would be a most beautiful dream; but you come down to its realities when you have to put all that is most interesting to you aside, in order to use most of your available time preparing the work of others for publication. However, ‘whatsoever thou puttest thy hand to, do it well.’”4

1 Harvard University Archives. Journal of Williamina Paton Fleming, March 12, 1900.  Page 18. (accessed January 12, 2015).
2 Harvard University Archives. Journal of Williamina Paton Fleming, April 18, 1900.  Page 22. (accessed January 12, 2015).
3Darlene R. Stille. Extraordinary Women Scientists. (Chicago: Children’s Press, 1995), 69.
4 Harvard University Archives. Journal of Williamina Paton Fleming, March 5, 1900.  Pages 9-10. (accessed January 12, 2015).

4George Johnson. Miss Leavitt’s Stars: The Untold Story of the Woman Who Discovered How to Measure the Universe. (New York: W. W. Norton & Co., 2005). 87.

Monday, January 12, 2015

Women “Computers” Explored the Cosmos – Part 3

When we left Mina, she had just been hired to be a human “computer” at the Harvard Observatory.

Some years before Mina’s exploration into the field of astronomy, Henry Draper directed an expedition to photograph the 1874 transit of Venus, and was the first to photograph the Orion Nebula, and the spectrum of Jupiter in 1880.

After Draper’s death in 1882, his widow funded the Henry Draper Medal for outstanding contributions to astrophysics. The Harvard Observatory used these funds to prepare the Henry Draper Catalog of stellar spectra, which are the pattern of lines caused by the dispersion of a star’s light through a prism placed before a telescope lens. This project would define Mina career.

It is left to question whether Mina assisted Pickering in developing a new system to catalogue the plates so they would be easily accessible and the data readily available, or if she developed the system herself as many sources state.1

This classification system, known as the Pickering-Fleming system, divided the stars into classes based on complexity of the spectrum lines. Using the system, Mina classified the tens of thousands of celestial photographs taken for the Draper Memorial.

For 30 years, Mina collaborated on the analysis of stellar spectrum photographs. While Mina was busy at her cataloging work, she discovered 79 stars, 10 novae, 59 gaseous nebulae, 9r Wolf-Rayet stars, and 222 long-period variables. She is also noted for her discovery of the Horsehead Nebula, a dark nebula in the constellation Orion, which is 1500 light years from us. I cannot even think in those distances.

In 1898 Mina was the first woman to receive the appointment of Curator of Astronomical Photographs. With this appointment came a tremendous amount of responsibility.

“In 1910 Fleming published her discovery of “white dwarfs” –hot, dense compact stars, usually white or bluish in color, which are in what is believed to be their final evolutionary stage.”2

In the next blog, we will see more of Mina’s accomplishments in the field of astronomy.

2Phyllis J. Read, Bernard L. Witlieb. The Book of Women’s Firsts: Breakthrough Achievements of Almost 1,000 American Women. (New York: Random House, 1992), 159

Thursday, January 8, 2015

Women “Computers” Explored the Cosmos – Part 2

As we continue exploring how women became so important to the study of astronomy, we must remember that because today we have so much information about the stars shining above us that it is easy to forget that most of that knowledge was discovered in the last century.

Until the early nineteenth century, even astronomers thought that the Milky Way was the extent of our universe. Referring to a story about how residents in a village triangulated distance, George Johnson said, “We were like the villagers in the canyon. Then we discovered a new way to measure.”1

As discussed in Part 1, Edward Pickering, Director of the Harvard Observatory, wanted his human “computers” to use the photographs provided by the Great Refractor to measure precisely the brightness (a clue to distance) and color (a clue to composition) of every star in the sky. A monumental undertaking. They were to do this by studying photographic plates of star collections.

Scottish-born Williamina (Mina) Patton Stevens Fleming, came to Boston from Scotland with her husband James, who abandoned her. This left Mina alone in a strange country, pregnant with no means to support herself. Pickering hired Mina as his housekeeper.

There is an unsubstantiated story about why Pickering hired Mina to work at the observatory. Supposedly, Pickering became so frustrated with an unsatisfactory male assistant that he said, “My housekeeper could do a better job.” If he, indeed , said this, he was right. I would hope it was at least partly because Pickering found her to be intelligent enough to do the work.

In the fall of 1879, Mina returned to Scotland to give birth to her son. In 1881, she became a permanent employee of the observatory.

In the next blog, we will look at what Mina was able to accomplish as a single-parent, housekeeper and astronomer.

1George Johnson. Miss Leavitt’s Stars: The Untold Story of the Woman Who Discovered How to Measure the Universe. (New York: W. W. Norton & Co., 2005). 8.

Monday, January 5, 2015

Women “Computers” Explored the Cosmos – Part 1

(Note: This is the beginning of a series of blogs about female astronomers who made history. I invite you to come along on the journey through the universe, with the sincere wish that you will ask questions and make comments.)

Have you ever looked up at a clear sparking night sky and considered counting the stars? I would never consider such a huge undertaking but many women, with scientific minds, did.

Galileo’s work on amplification in order to view the stars advanced by huge leaps in the late 19th century with the use of the Great Refractor in the new Harvard College Observatory, run by young physicist Edward Charles Pickering. Now in retirement, the Harvard telescope in 1847 was one of the most powerful in the world. The telescope came to be because of the embarrassment of the wealthier citizens of Boston when Harvard did not have a telescope strong enough to join in the excitement of the March 1843 comet.

With the potential discoveries this new refractor provided, the Harvard Observatory embarked on a project to catalog the position, color and brightness of every star in the sky. Pickering, director, from 1877 to 1919, needed bright, meticulous and dedicated human number crunchers he called “computers” to do thousands of complex astronomical computations that followed a painstaking process of manually counting and computing the images revealed in thousands of photographs of star fields. AND he needed them to work for low wages.

“A great savings may be effectuated by employing unskilled and therefore inexpensive labor, of course under careful supervision,” Pickering reasoned.1 

Women accepted this challenge because it provided them an avenue into the field of astronomy. Henrietta Swan Leavitt, Annie Jump Cannon and Williamina Paton Fleming were three of these women.

1George Johnson. Miss Leavitt’s Stars: The Untold Story of the Woman Who Discovered How to Measure the Universe. (New York: W. W. Norton & Co., 2005). 18.