Thread by @natlibscot

On #InternationalWomensDay let's talk about Williamina Fleming (1857-1911).

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Williamina was born in Dundee, the daughter of a carver and gilder with premises in the Nethergate. She left school when she was 14 and became a pupil-teacher.

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In 1877, Williamina married James Orr Fleming, an accountant and fellow Dundonian. She worked as a teacher for a short while, before the couple emigrated to America (specifically Boston, Massachusetts) when Williamina was 21.

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Unfortunately, Williamina's husband left her when she was pregnant and she was then forced to support herself and her new child. She searched and found work as a maid at the home of Edward Pickering, Director of the Harvard College Observatory.

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Pickering's wife Lizzie recommended Williamina as having talents outwith her usual duties and in 1879 Pickering hired Fleming to conduct part-time administrative work at the observatory.

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Williamina quickly became a fulltime copyist and 'computer' at the observatory — 'computer' was then the word for someone who analysed information.

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At that time Pickering had just embarked on an extensive program of celestial photography. Williamina's job involved examining spectra — the breakdown of light from stars — on photographic plates.

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Pickering's technique involved placing a prism in front of the telescope lens to capture the spectral image from each star. In Williamina's day, the spectra on photographic plates would appear in light or dark bands like in this image.

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Each star would have its own distinctive spectrum and the lines on the spectrum indicate chemical composition. In this way, astronomers were (and are) able to gain a lot of information on the properties of any star including its temperature.

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At the time of her death, Williamina had handled over 200,000 fragile plates and discovered a total of 59 gaseous nebulae, over 310 variable stars, and 10 novae.

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Most notably, in 1888, Williamina discovered the stunning Horsehead Nebula.

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Williamina received considerable recognition for her work and became the leading female astronomer of her day. She was made an honorary member of the @RoyalAstroSoc in 1906, and was presented with a medal by the Astronomical Society of Mexico.

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We've got lots more info about Williamina Fleming (and other Scottish women of science) in our learning resource > nls.uk/learning-zone/…

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Thanks for reading this wee thread and happy #InternationalWomansDay

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PS - Dava Sobel's book 'The Glass Universe' talks about Williamina and the Harvard Observatory and is well worth a read.

You can request it at the Library via this link > search.nls.uk/primo-explore/…

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PPS - this tweeter wrote the whole thread at once and posted it... and then only the first two tweets appeared (this tweeter didn’t keep a copy). Cue *lots* of angry muttering, slapping of own head and re-typing. Anyway - glad people enjoyed it (and it was worth re-doing) 👍