Marjorie Pettit Meinel (born Marjorie Steele Pettit; May 13, 1922 – June 24, 2008) was an American astronomer and optical scientist. For over 60 years she was the research collaborator and wife of fellow astronomer Aden Meinel. Her research focused on telescope design and optics, the technological applications of solar energy, atmospheric phenomena including the optical effects of volcanic eruptions, and the study of variable stars. Biography Marjorie Steele Pettit was born in Pasadena, California May 13, 1922, to astronomers Edison Pettit and Hannah Steele Pettit who were based at the Mount Wilson Observatory. Meinel's older sister, Helen, also became an astronomer. As a teenager, Meinel assisted her father in making the first time-lapse photography of solar prominence eruptions, using a movie camera and a quartz-polarising monochromator attached to the 6-inch Alvan Clark refracting telescope at their home. As her mother's health declined Meinel increasingly assisted her father's research on the telescope at home and at the observatory. While at Pasadena Junior College Marjorie met and began dating fellow pupil Aden Meinel, urging him to study astronomy. In 1941 she began studying astronomy at the University of California, Berkeley, and in 1942 transferred to Pomona College in Claremont, California to be closer to family. She also began teaching some classes at the university, including training airmen in celestial navigation. For her masters research at Claremont Colleges she used the family telescope in 1943–1944 to study the variable red giant RT Cygni. Her thesis research was published by the Astronomical Society of the Pacific. In 1944 she married Aden. From 1944 to 1945 she worked as a research associate at the California Institute of Technology working on military rockets. She also worked in the editorial staff of the Office of Scientific Research and Development preparing and editing reports, including reports for the Manhattan Project. She resigned when the war ended. In 1946 she moved with Aden to Berkeley, California, where he was to continue his studies. Later that year she gave birth to the first of seven children, the final child born in 1957. While raising their children she was not employed, but remained scientifically active, collaborating in Aden's research, attending conferences, and editing their work. Meinel co-authored two papers during this period, both on the optical effects of volcanic eruptions on the atmosphere. The Meinel's 1967 paper was the first to suggest that the optical effects on sunsets and sunlight