stfuconservatives: From Wikipedia: Cecilia Payne-Gaposchkin (May 10, 1900 – December 7, 1979) was an English-American astronomer who in 1925 was first to show that the Sunis mainly composed of hydrogen, contradicting accepted wisdom at the time. … Shapley persuaded Cecilia Payne to write a doctoral dissertation, and so in 1925 she became the first... - http://dendroica.tumblr.com/post...