Background

Williamina Paton Fleming was born on May 15, 1857, in Dundee, Scotland. She was the daughter of Robert and Mary (Walker) Stevens. Her father had a profitable carving and gilding business and was well known for his picture frames. He was also one of the first in Dundee to experiment with photography. He died when his daughter was seven.

Education

Fleming attended public schools in Dundee until she was 14.

Career

Williamina worked as a teacher a short time before the marriage, when she with her husband emigrated to Boston, Massachusetts. After the divorce Fleming found it necessary to support herself and her infant son. In 1881, after a period of domestic work for Edward C. Pickering, the new director of the Harvard College Observatory, she became a fulltime copyist and computer at the observatory itself.

In 1881, Pickering invited Fleming to formally join the HCO and taught her how to analyze stellar spectra. She became one of the founding members of the Harvard Computers, an all-women cadre of human computers hired by Pickering to compute mathematical classifications and edit the observatory's publications. In 1886, Fleming was placed in charge of the group. At that time Pickering had just embarked on an extensive program of celestial photography. Through her studies of the objective prism spectrum plates, usually in collaboration with Pickering, Fleming became the leading woman astronomer of her day. Her suspicions aroused by the spectral peculiarities she observed, she discovered more than 200 variable stars and ten novae - the latter being a significant fraction of the twenty-eight novae recorded up to the time of her death.

She also classified 10,351 stars in the Draper Catalogue of Stellar Spectra. The spectra were organized into seventeen categories, lettered from A to Q, but 99.3 percent of the stars fell in the six classes A, B, F, G, K, and M. Although it was a great advance over the four types into which Angelo Secchi had visually classified about 4,000 stellar spectra, Fleming’s system was soon to be enormously refined at Harvard by Annie Jump Cannon.

Fleming’s keen eyesight, remarkable memory, and industrious nature enabled her to advance to a position of considerable authority at the observatory, so that ultimately she gave assignments to a corps of a dozen women computers. In 1899 she was appointed curator of astronomical photographs, and by 1910 she had examined nearly 200,000 plates.

Achievements

• Williamina Fleming is noted for her discovery of the Horsehead Nebula in 1888. She also helped develop a common designation system for stars and cataloged thousands of stars and other astronomical phenomena. The Fleming lunar crater was jointly named after her and Alexander Fleming.

Works

More photos

• book

  • Spectra and photographic magnitudes of stars in standard regions 1911
  • Stars having peculiar spectra 1907

Membership

Fleming was a member of the Royal Astronomical Society and the French and Mexican astronomical societies.

Connections

In 1877, Williamina married James Orr Fleming, an accountant and widower, also of Dundee. They divorced after the birth of their child.

Father:

Robert Stevens

Mother:

Mary (Walker) Stevens

Spouse:

James Orr Fleming

Son:

Edward Pickering Fleming

References

• Dictionary of Scientific Biography