Many articles and books describe the rise to fame of maid-turned-astronomer Williamina ‘Mina’ Paton Fleming (1857–1911) and her contributions to stellar classification. But her deep sky discoveries may hold a few surprises. In 1879, after emigrating to Boston from Scotland, her husband abandoned her while she was expecting their son. Seeking employment, Fleming found it when Edward Charles Pickering, director of Harvard College Observatory (HCO), hired her as his second housekeeper.
In the late 1870s, Pickering had initiated an ambitious program in stellar photometry (precise measurement of stars’ brightnesses) at HCO using a visual instrument he devised that he called a meridian photometer. During the day, an assistant would transcribe Pickering’s observing notes from the night before and then apply corrections to compute stellar magnitudes. Legend has it that the sloppy work of a male assistant upset Pickering so much that he complained that even his Scottish maid could do a better job! Soon afterward, he offered Fleming full-time employment in the lab as a copyist and computing assistant.
The timing corresponded with advances in spectroscopy that shifted the focus of the observatory. In the 1860s, stellar classification relied on time-consuming and exhaustive visual observations made with a spectroscope. Wealthy amateur and pioneering astrophotographer Henry Draper was the first to photograph distinct lines in a stellar spectrum in 1872. By placing a quartz prism in front of the focus of his 70cm (28inch) reflector, he captured four hydrogen absorption lines in Vega’s spectrum. In the next few years, Henry and his wife, Mary Anna Palmer Draper, recorded the spectra of more than 100 bright stars from his private observatory in New York.
After Henry passed away in 1882, Mary Anna wished to honour and further her husband’s spectroscopic research.
With encouragement from Pickering, she established the Henry Draper Memorial fund in 1886.
Pickering used the
