Photo from the Smithsonian Institution Archives
Acc. 90-105 – Science Service, Records, 1920s-1970s, Image # SIA2009-1326
Thanks to @STEMWomen, who noted on twitter that “Cecelia Payne-Gaposchkin discovered that the sun is mainly composed of hydrogen,” citing this Facebook page from Astronomy/Astrophysics History and News.
The American Museum of Natural History has an online excerpt about Cecilia Payne from COSMIC HORIZONS: ASTRONOMY AT THE CUTTING EDGE, edited by Steven Soter and Neil deGrasse Tyson, a publication of the New Press. © 2000 American Museum of Natural History.