Charlotte Moore Sitterly | |
|---|---|
 Sitterly in 1988 | |
| Born | Charlotte Emma Moore (1898-09-24)September 24, 1898 Ercildoun,Pennsylvania, U.S. |
| Died | March 3, 1990(1990-03-03) (aged 91) Washington, D.C., U.S.[1] |
| Alma mater | |
| Awards | Annie Jump Cannon Award in Astronomy(1937) Federal Woman's Award(1961) Bruce Medal(1990) |
| Scientific career | |
| Fields | Astronomy |
| Institutions | |
| Thesis | Atomic lines in the sun-spot spectrum (1931) |
Charlotte Emma Moore Sitterly (September 24, 1898 – March 3, 1990) was an Americanastronomer.[2] She is known for her extensive spectroscopic studies of the Sun and chemical elements. Her tables of data are known for their reliability and are still used regularly.[3]
Charlotte Moore was born to George W. and Elizabeth Walton Moore inErcildoun,Pennsylvania, a small village nearCoatesville. Her father was the Superintendent of Schools forChester County and her mother was a schoolteacher. Her parents were Quakers and Charlotte was a lifelong member of Fallowfield Friends Meeting.[4]
She attendedSwarthmore College, where she participated in many extracurricular activities such as ice hockey, student government, glee club, and tutoring. In order to pay her tuition, Moore was a substitute teacher, one of the few ways she thought she could work her way through college.[4][5] She wanted to pursue a career outside teaching because "I did not enjoy the teaching that I did from first grade through high school. I succeeded at it, but I didn’t like it; it was too wearing."[5]
Moore graduated from Swarthmore in 1920 with aBachelor of Arts degree in mathematics and went on toPrinceton to work as ahuman computer.[6]
On the recommendation of her mathematics professor at Swarthmore, John. Miller, Moore obtained a job at the Princeton University Observatory working for ProfessorHenry Norris Russell as a human computer carrying out calculations needed to use photographic plates in determining the position of the Moon.[4] While working for Russel, Moore initially felt nervous about her inexperience, but over time her interest in astrophysics began to blossom.[5] Russell and Moore researched binary stars and stellar mass, and published extensively on the subject over the years of their collaboration.[3] Her research included an effort to classify 2500 stars based on their spectra.[7]
Although she spent five years at Princeton working under Russell, he refused to consider her a PhD, an unexceptional fact since there were no women in any of Princeton's graduate programs until 1961. Moore said “I was used to prejudice against women because Princeton was a man's stronghold, and a woman was really out of step there.”[8] Though in 1926, Russell left his own name off a paper they worked on together and used hers alone.[8]
After five years at Princeton, Moore took a leave of absence due to ill health and she moved to theMount Wilson Observatory as part of an ongoing collaboration between Russell and research groups there.[8] While at Mount Wilson she worked extensively on solarspectroscopy, analyzing the spectral lines of theSun and thereby identifying thechemical elements in the Sun. With her collaborators, she analyzed the spectra ofsunspots.[3] Moore was able to deduce the temperature of sunspots to be about 4,700kelvins.[8] Her pictures from the Mount Wilson Observatory helped redetermine the new InternationalAngstrom scale.
She earned a Ph.D. inastronomy in 1931 from theUniversity of California, Berkeley, which had more relaxed rules on women graduates than Princeton, on a Lick Fellowship. Princeton still did not accept women – and would not for the next 30 years.[6][4] While working on her Ph.D, she continued researching spectroscopy and collected and analyzed data about the spectra of chemical elements and molecules. After obtaining her Ph.D, she returned to Princeton to continue work with Russell as a research assistant.[6]
One of her most significant contributions to physics was her identification of technetium in sunlight, the first example of technetium naturally existing. She joined the thenNational Bureau of Standards (NBS) in 1945.[9] Her tables of atomic spectra and energy levels, published by NBS, have remained essential references in spectroscopy for decades. While there, she began to research the infrared solar spectrum and atomic energy levels.[4] Beginning in 1946, Moore was able to extend her work onultraviolet spectral lines thanks to the work ofRichard Tousey and measurements taken onV-2 rockets; prior to this Moore's studies were limited to telescopic observations partially blocked by the Earth's atmosphere. Moore collaborated with Tousey for decades and led to her 1950 publication "Ultraviolet Multiplet Table."[8]
In 1949 she became the first woman elected as an associate of theRoyal Astronomical Society of Great Britain, in honor of her work onmultiplet tablets and in identifyingsolar spot electra. Throughout her career she authored and co-authored over 100 papers and attended the tenth general assembly of theInternational Astronomical Union on the Joint Commission on Spectroscopy in Moscow in 1958.[6] Sitterly retired from her position at the NBS when she turned 70, in 1968, but continued her research at theNaval Research Laboratory.[10] Sitterly was honored by theJournal of the Optical Society of America by a commemorative issue in 1988.[11]
While working at Princeton in the 1920s, she met physicistBancroft W. Sitterly, whom she eventually married on May 30, 1937.[5] She continued to publish journals under her maiden name because most of her recognition was under that name. She believed that traveling is one of the most important aspects of a scientist's life, as it promotes collaboration between scientists. She enjoyed gardening, traveling, and music with her husband until his death in 1977. She continued her research until her death from heart failure at the age of 91.[6]
Awards
Service
Named after her
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