
Sunspots, American, 12 August 1917.
- Made:
- 1917 in California, United States and Mount Wilson

Photograph film positive, 16" x 20", the Sun, photographed with the 60ft Tower Telescope of the Mount Wilson Observatory, 1917 August 12, Large groups of sunspots lying in zones parallel to the Sun's equator, size of image 15" x 19"