Bouquin, left, and Smith Zrull, right, hold up an original image of Williamina Fleming posing in the plate stacks in a 1891 photo that was the first photo used in bestselling author Dava Sobell's 2016 book, "The Glass Universe." Smith Zrull says they know the 1891 image is posed because a window is closed and the tool Fleming is using to study a plate only works with window light. 


Alex Newman/PRI