DASCH

DASCH (Digital Access to a Sky Century @ Harvard) is a project to digitize photographic plates of astronomical observations, glass plates held by the Harvard College Observatory taken from 1885 to 1992. The project was established in 2001, and plate scanning was completed in 2024 (415,848 plates), but efforts continue to analyze them, in particular, to establish the mapping of plate and point on the plate to corresponding celestial coordinates, for the benefit of astrometric information.