I. Dr. Cecilia Payne-Gaposchkin (Born Cecilia Helena Payne, Wendover, England, May 10, 1900) was a British-American astrophysicist and astronomer who specialized in the classification of stars. She was related to some notable figures such as historian Heinrich Pertz due to her mother’s family. However, her father died when she was only four years old and her mother was left taking care of the three siblings. She attended the independent all-girls St. Paul’s School and won a scholarship to Oxford in 1919 where she studied botany, chemistry, and physics. The following year she went to a lecture held by the knighted physicist Arthur Eddington about his famous expedition in 1919 to prove Einstein’s Theory of General Relativity via the observation of a total solar eclipse. This was described as a life-changing moment for her and she said “The result was a complete transformation of my world picture. My world had been so shaken that I experienced something very like a nervous breakdown.” about the lecture and fell in love with astrophysics and astronomy. She later talked with Eddington who encouraged her to keep pursuing her studies and despite the fact that she finished her schooling at Oxford, she was never awarded a degree due to the fact that Oxford would not grant its first degrees to women until 26 years later. In 1923 she became the second recipient of a grant that was created to encourage women to study at the Harvard College Observatory. She left the United Kingdom that very same year and went immediately into the astronomy graduate program where she built off of the work of people already working at the Observatory and the ionization equations theorized by Meghnad Saha to (Otto Strube and Velta Zebers say) write “undoubtedly the most brilliant Ph.D. thesis ever written in astronomy”. This made her the first ever person to receive an astronomy doctorate from Radcliffe College, which would later be assimilated into Harvard, in 1925 (at the age of 25!). Leading up to the publication of her second academic book, Payne continued making observations at Harvard and with her team she made millions of observations on high luminosity and variable stars. One year after publishing her 1930 book Stars of High Luminosity, Payne became an American citizen and in 1933 while traveling Europe she met the Russian astronomer Sergei Gaposchkin whom she helped get a visa to the United States. They married the next year and settled in Lexington, Massachusetts and frequently made astronomical observations together in further research. Although Cecilia Payne-Gaposchkin researched at Harvard for her entire academic career, she often had doubts about staying, especially in her early years there. Until 1938 she was simply listed as a technical assistant to Observatory Director Harlow Shapley who later lobbied for her title to be changed to Astronomer and she get a salary increase. She also became a fellow at the American Academy of Arts and Sciences in 1943. However, despite her numerous contributions to the field and her amazing track record, none of the classes that she taught were formally recorded as classes until after 1945. In 1954, when a new director Donald Menzel was appointed, her position was changed and she became the first female at Harvard to become a non-Associate/Assistant professor (and the first one with tenure) and later she was also the first female department head as the Chair of the Astronomy Department. Even after retiring from teaching in 1966, she continued observing at the Smithsonian Observatory and editing scientific journals from Harvard for over 20 years, and she even published an autobiography as part of her will (originally called The Dyer’s Hand and later reprinted as Cecilia Payne-Gaposchkin: An Autobiography and Other Recollections).II. Back in the early 1900’s the fields of astronomy and astrophysics were still in their fledgling states (especially compared to today) and had multiple incorrect assumptions about stars and their inner workings (one of which I shall talk about later). Besides the lack of knowledge in the field, a simple lack of data was apparent and the observations conducted by Payne-Gaposchkin and her team laid the groundwork from which most observations and theories about high luminosity and variable stars are based. She also used these observations to theorize the life-cycle of a star and she continued to make observations and made many contributions to the field in the subsequent years. In her doctoral thesis, Payne-Gaposchkin stated that even though the Sun had many elements on it that were also found in the same amounts on Earth, however, she also found (in direct opposition with the generally accepted wisdom at the time) that the Sun was mostly hydrogen and thus had a very different composition than that of rocky planets. While editing her thesis, Henry Norris Russell advised her not to include that last finding due to the controversy it could spark. Four years later he reached the same conclusion via different methods and published a book in which he acknowledged that Payne-Gaposchkin had made the observation before him. However, he is still mainly accredited with this discovery despite his multiple attempts to give the true discoverer the limelight.