Preserving the legacy of the Women Astronomical Computers of the Harvard College Observatory

Plate D20271, found during recent cabinet inventories, pictures Women Astronomical Computers with observation instruments at the Harvard College Observatory, circa 1920s. Seven of the nine women pictured are yet to be identified. Margaret Walton Mayall, a Woman Astronomical Computer, is second from the left and Cecilia Payne-Gaposchkin, the first person to earn a PhD in Astronomy from Harvard, is in the back row, second from the right. Image credit: Astronomical Photographic Glass Plate Collection, Harvard College Observatory.

The following post was written and contributed by Lisa Bravata, Curatorial Assistant, Astronomical Photographic Plate Collection, Harvard & Smithsonian Center for Astrophysics

The Harvard College Observatory began strategically building its collection of astronomical photographic plates shortly after the invention of dry plate photography in the 19th century. Harvard astronomers’ prolific output of photographs needed to be carefully analyzed, a tedious process of taking measurements and mathematical calculations. Women could be hired at a cheaper rate than men to do this work, and today we know that over 200 Women Astronomical Computers at the HCO helped advance our modern understanding of the Universe. 

The swarm of markings on this plate, MC27415, were made by Muriel Mussells Seyfert, a Woman Astronomical Computer. Her many notations point to potential galaxies, including the great spiraling Andromeda Galaxy near the center of the image. Image credit: Astronomical Photographic Glass Plate Collection, Harvard College Observatory.

By the late 20th century, the dominance of digital technology altered the way astronomers worked and there was less reliance on the photographic plate collection. During this time, the digitization project DASCH was conceived to make HCO’s glass plate negatives accessible for modern scientific research. For decades, this project left little time or resources for preserving the legacy of the Women Astronomical Computers. When the pandemic forced staff to remote work, Curator of Astronomical Photographs, Lindsay Smith Zrull, excitedly pivoted staff to researching and gathering as much information as possible about these women. The result of their research is a list of 216 individuals that Zrull published in 2021*. 

Building on the success of this research, the Plate Stacks was able to transition in 2022 from a departmental collection into an archival collection within the Harvard Library system. Curatorial assistants are now working to inventory all the objects and materials in the collection for the first time. Previously, only the glass plates and their original jackets were well documented, but we quickly realized that the Plate Stacks and everything inside this space holds context and historic value. Our challenge is how to archive a collection you are actively working inside of. There are “mystery” cabinets to have unlocked and inventoried, objects once thought of as office supplies are being appreciated in a whole new light (personalized stationery from a past curator was, in fact, not scrap paper), and photos pinned to the bulletin board decades ago are being moved to more appropriate archival housing. 

Rehousing archival photos found while inventorying at the Harvard Plate Stacks.

The transition to Harvard Libraries affords the Plate Stacks a unique opportunity to evaluate its user communities and make the collection more accessible to wider demographics. In the past, writers, artists, historians, and students have all made their way to the collection by their own committed research. Conservators are equally interested in the collection, which has detailed records of the photographic process, including date and length of exposure, along with documentation for how they have been stored over time. These are the underserved users we have in mind while developing finding aids from the inventory, arrangement, and description process we’re currently undertaking. 

While there were plenty of setbacks during the pandemic, the Plate Stacks were fortunate to be able to take that time to consider the potential of the collection and it is now in a better position to grow its users within and beyond the field of astrophysics. 

*Smith Zrull, L. (2021). Women in Glass: Women at the Harvard Observatory during the Era of Astronomical Glass Plate Photography, 1875–1975. Journal for the History of Astronomy, Vol. 52(2), 115–146. DOI: 10.1177/00218286211000470 journals.sagepub.com/home/jha.