This biography is reprinted with permission from Making Visible the First Women in Astronomy in Australia: The Measurers and Computers Employed for the Astrographic Catalogue by Dr Toner Stevenson, published 1 April 2014 with Cambridge University Press. Her article Melbourne Observatory’s Astrographic Women: Star Measurers and Computers was published in the Journal of Astronomical History and Heritage, Volume 26, Issue 2: 325 – 338 in 2023.
Born: 28 March 1861, Australia
Died: 3 September 1910
Country most active: Australia
Also known as: NA
Mary Emma Greayer worked at Adelaide Observatory from 1890 to 1898. She was employed as a temporary assistant at Gepps Cross and then Angaston public school in 1886 (South Australian Register 1886). In 1887 her sister, Jessie Greayer, married William Ernest Cooke, assistant government astronomer.
Because Greayer was not a permanent staff member her name does not appear in the Public Service Gazette or in official staff records in which only permanent staff are listed. It is through the Time Book, as shown in Figure 2, that evidence of Greayer’s regular night work from December 1890 is found and the 1897 Adelaide Observatory MNRAS report (Todd Reference Todd1897b). Furthermore the initials ‘M.E.G.’ in the handwritten logbooks of observations and reductions recorded the extent of Greayer’s work, which included observing through and calibrating telescopes.
Greayer regularly worked in partnership with Cooke on three or more nights per week from 1891 and when Cooke resigned in 1896 Richard Fletcher Griffiths became her observing partner. The 1893 observing logbook lists Greayer as the main observer of Individual Zenith Stars (Adelaide Observatory 1893). She took micrometer readings and reduced the nadirs. The diary notes indicate that she adjusted the 6-inch Troughton and Sims Transit Circle telescope pictured in Figure 3 and calibrated other instruments. This work is in six volumes and each volume holds details of an estimated 990 stars. Greayer observed and reduced many hundreds of clock stars also with the transit instrument.
At night Greayer observed over one third of the positional stars for the Melbourne AC zone between 1894 and 1898 using the 8-inch equatorial telescope. During the day, between 1895 and 1897, Greayer reduced the Melbourne Astrographic Zone stars (−65° to the South Pole) from apparent to mean RA and NPD (Adelaide Observatory 1897). Cooke and Greayer observed the Stars from the General Argentine Catalogue to compare magnitude observations (Adelaide Observatory, 1892).
Greayer’s interest in astronomy and curiosity about new developments led her to be one of the first three women to join the Astronomical Society of South Australia (ASSA) in 1893. Her acceptance into the society with Lorna and Alice Maud Todd was reported in the newspaper (The Advertiser 1894), as the ASSA was one of the first astronomical societies to enrol women as members without prejudice. In 1895 South Australia was the first state in Australia to grant women suffrage.
Greayer’s significant contribution to the astronomical work was highlighted at the time of her resignation in 1899 from the correspondence between Todd and Baracchi:
‘Since Mr Griffith’s marriage which has deprived me of Miss Greayer’s services we have been unable to observe any of your Astrographic stars. . .’
(Todd Reference Todd1899a)
Todd also wrote to NSW Government astronomer, H.C. Russell, about Greayer, praising her as ‘a veritable Caroline Herschel’ bemoaning that, after Greayer’s departure, the work of measuring standard stars for the AC ‘stalled’ for a number of years (Todd Reference Todd1899b). Greayer married Griffiths in 1898 and they had four children. Greayer died on 3 September 1910 aged forty-nine in Victoria.