Astronomical Photographic Glass Plate Collection

Black and white image of Orion's belt and horsehead nebula
Section of plate B2312 (1888) showing Orion's belt and the horsehead nebula.

Harvard College Observatory's Astronomical Photographic Glass Plate Collection is the largest archive of its kind in the world. Housing over 550,000 direct photo and spectral images, covering both the northern and southern hemispheres, the Glass Plates make up over a century of irreplaceable scientific observations and represent the first full image of the visible Universe. Hundreds of women studied and curated the Glass Plates while making discoveries of their own, but more often than not their work went unrecognized. The Observatory is dedicated to understanding and undoing the erasure of these women’s contributions while advancing and enabling the creation of new knowledge using the Glass Plate Collection.

Plate Stacks Tours

Tours and in-person research visits to the Plate Stacks are temporarily suspended. Thank you for understanding.

Find out more about tours here