Harvard-Smithsonian Center for Astrophysics Harvard Observatory Plate Stacks A Series Plate Centers Click here for temporal distribution

Entire Series (23847 plates)

1890-1900 (3678 plates)

1900-1910 (5369 plates)

1910-1920 (1680 plates)

1920-1930 (2517 plates)

1930-1940 (5866 plates)

1940-1950 (4373 plates)

1950-1960 (350 plates)