data. Her salary was 25 cents, half the amount paid to men at that time. In 1887, Edward Charles Pickering had found the first spectroscopic binary or double star, ζ1 Ursae Majoris (Mizar A). Maury was asked to determine its orbit, which she did using periodic doubling of some of the lines in its spectrum. Then, in 1889, Maury discovered a second spectroscopic binary, Beta Aurigae, and calculated its orbital period. Learning of this work from a copy of the Annual Report of the Henry Draper Memorial, eminent astronomer John Herschel recognized the importance of her achievements by writing to Pickering, the observatory's director. Herschel asked Pickering "to convey to Miss Maury my congratulations on having connected her name with one of the most notable advances in physical astronomy ever made." However, when the first spectroscopic binary and its orbit were more widely reported, the name connected with it was Pickering. The discovery was announced by Pickering in a presentation to the Philadelphia meeting of the National Academy of Sciences on November 13, 1889. The work was described in a paper "On the Spectrum of Zeta Ursae Majoris", which appeared in the American Journal of Science in 1890. In both cases the only mention of Maury was a single line, stating that "a careful study of the results has been made by Miss. A. C. Maury, a niece of Dr. Draper". The sole author credit was given as Pickering. In 1888, Maury was assigned to observe stellar spectra of bright stars in the northern celestial hemisphere and catalog them. Her work contributed to the construction of the Henry Draper Catalogue. By 1924, the catalogue would contain 225,300 stellar spectra, described in terms of their characteristics. By 2017, it would have 359,083 entries. The Harvard Observatory staff used an alphabetical system of classification designed by Williamina P. Fleming and Annie Jump Cannon. Maury found their classification system inadequate and developed her own. It was considerably more detailed and included information about temperature and about the width, distinctness, and intensity of spectral lines. In 1891 Maury left the observatory and started teaching in the Gilman School in Cambridge, Massachusetts. Pickering asked her to return and complete her observations, and she said that she was uncomfortable completing her research if her work was unacknowledged. She returned in 1893 and 1895 and published her observations of stellar spectra in an important catalogue of classifications