A Scientific Biography of Cecilia Payne: Women in Astronomy When someone mentions some of the famous astronomers, what we always hear are names like Isaac Newton, Edwin Hubble or Harlow Shapely. However, there was actually one name among the 20th century astronomers that did occasionally come up, separated itself from the mainstream, and broke down the major barriers of sciences. That is the name of Cecilia Payne, who succeeded in working with the astrophysics of stellar composition. Born in Wendover, England in 1900, Cecilia developed an interest in astronomy when she was at the age of five after witnessing a meteor in the sky. In the year 1919, Cecilia won a scholarship to enter the Newham College at Cambridge, however, with the intention to study botany at first. The attraction of astronomy didn’t dominate her life until she had a chance to attend Sir Arthur Eddington’s lecture on Albert Einstein’s theory of relativity. Cecilia was so enthusiastic that after the lecture, she was able to “write out virtually verbatim what she had heard, later checking it as correct against a printed version”(Wayman 1.27). And it was the same enthusiasm that made her give up botany and turn towards astronomy. However, her career of astronomy wasn’t a smooth sailing at all time. Not only that women were not granted degrees at Cambridge at the time when Cecilia completed her studies, Cecilia also had experienced a feeling of discrimination especially when one of her professors at Cambridge, called F J M Stratton, expressed that Cecilia “could never hope to be other than an amateur astronomer”(Wayman 1.27). With so much concern about her own future, Cecilia headed toward the U.S. where she thought a women astronomer might have more opportunities and obtained a fellowship to study at Havard Observatory, which she called a “stony-hearted stepmother”. Cecilia’s life at Harvard Observatory marked a turning point of her career in astronomy. At there she started her research on the stellar spectra and began the research by measuring the absorption lines in stellar spectra. It was also at Harvard Observatory that Cecilia became the first women to receive a Ph.D degree in astronomy for her thesis “Stellar Atmospheres, A contribution to the Observational Study of High Temperature in the Reversing Layer of Stars”. While applying physicist Saha’s theory of ionization that states “each element stands out vividly in a stellar spectrum only at a particular temperature and pressure”, Cecilia looked into numerous spectrums and the lines and was able to verify that the variation in stellar absorption lines is due to the different ionization states occurred at different temperature, instead of the abundance of elements. (Bartusiak 37). Her work allowed her to relate the spectral classes of stars to their actual temperatures. The most well known part of Cecilia’s discoveries is that she was the first to suggest that although the earth and the stars share common elements, the stars in particular were made mostly of Hydrogen based on spectra from lots of stars. Specifically Cecilia’s research suggests that hydrogen is “a million times more plentiful in the stars than it is on the earth”(Bartusiak 37). No one believed her at the time because it was known that earth wasn’t mostly made up of hydrogen. It was noted that Porfessor Russel from Princeton even suggested that the result was “clearly impossible”(James, pars.22). As a result it took years for astronomers to accept her idea and now we know that she was absolutely right. Our understanding of the universe has been affected by Cecilia’s accomplishments in many ways. It is not until we know stars’ major compositions that we started to explore what is actually going on inside. Because the astronomers realized that stars are mostly hydrogen, they could suggest that hydrogen fusion is their power source. And that Stars are powered by converting hydrogen into helium and therefore could survive billions of years. From there we begin to grasp the realities of stellar life cycles that originated from Payne’s thesis. Overcoming numerous obstacles, Cecilia became Harvard’s first female professor and was named the university’s first female department chair. Back in time when there were not a lot women getting recognized, Cecilia was definitely a pioneer and her impact on science and social equality were both significant to the history of mankind. Cecilia’s huge success not only marked a turning point of the Harvard Observatory, but also of women in astronomy in general by inspiring more and more women to enter the mainstream of the field of astronomy.