The 'Harvard Computers' who cataloged the stars worked at which institution?

Harvard College Observatory, where from the 1880s a staff of women was hired to measure and classify stellar spectra recorded on glass photographic plates. Computer was the job title - a person who computes - and they were paid roughly 25 to 50 cents an hour, less than a clerk, which is a large part of why the observatory could afford so many.

The work they did was not clerical. Annie Jump Cannon classified around 350,000 stars by hand and devised the spectral sequence still in use - O, B, A, F, G, K, M - by reordering an alphabetical scheme into a physically meaningful one. Antonia Maury spotted the line widths that distinguish giants from dwarfs. Williamina Fleming, who had been the director's housemaid, found the Horsehead Nebula and dozens of novae.

Two results changed cosmology outright. Henrietta Swan Leavitt found that a certain kind of variable star pulses at a rate set by its true brightness, which gave astronomy its first reliable way to measure distance and is what Hubble used to prove other galaxies exist. Cecilia Payne then showed, in her 1925 thesis, that stars are made overwhelmingly of hydrogen - a conclusion her reviewer pressed her to disown as almost certainly not real, and which he later confirmed himself.