June 9, 2016
As everyone knows, the sciences have traditionally been male-dominated professions. Worse than that, scientists and engineers have a history of being downright misogynist. One glaring example of my generation is the mnemonic for electronic component color code. In those days before rapid printing of fine pitch numeric characters on odd-shaped objects, resistance, capacitance, and inductance values were specified by bands of color.
The colors, black, brown, red, orange, yellow, green, blue, violet, gray, and white, represented the numbers zero-nine. The mnemonic I learned in the dark corner of the lab was "Bad boys rape our young girls but violet gives willingly." Violet is still a common name today, ranking 77th as a girl's name in the current decade.
Stars do not have the same spectral characteristics, since the hotter stars are more blue, and the cooler stars are more red. These different spectral types are identified by a letter code. Astronomers were somewhat less crude in their mnemonic for stellar classification.
For historical reasons, the spectral star types were designated, O, B, A, F, G, K, M. Our Sun is a type G star; more specifically G2V. The astronomer's mnemonic for the stellar classification is, "Oh, be a fine girl, kiss me!" The one that I learned had three additional spectral types, R, N, S at the end, so the mnemonic I learned was "Oh, be a fine girl, kiss me right now, smack!"
Despite the fact that women were not really welcomed in the sciences, there have been quite a few prominent female astronomers, the earliest example being Caroline Herschel, the sister of the astronomer, William Herschel. I wrote about Caroline Herschel in an earlier article (Sexism in Science, September 28, 2012).
While Edwin Hubble is credited with discovering the expanding universe that's been a fundamental topic of modern astronomical observations, it was a discovery by American astronomer, Henrietta Swan Leavitt (1868-1921) that allowed Hubble's conjecture. Leavitt discovered the proportionality between the period and luminosity of the Cepheid variable stars.
These stars are named after the star, Delta Cephei, discovered to have variable luminosity in 1784. As Leavitt and her employer/colleague, Edward C. Pickering, wrote in volume 173 of the Harvard College Observatory Circular,
"A straight line can readily be drawn among each of the two series of points corresponding to the maxima and minima, thus showing that there is a simple relation between the brightness of the variables and their periods... Since the variables are probably at nearly the same distance from the Earth, their periods are apparently associated with their actual emission of light..."
Leavitt graduated from Radcliffe College, Harvard's female outpost, in 1893, and she joined the Harvard College Observatory. Her title there was "computer," and her work was to translate the images of stars on photographic plates to useful data. That's how her Cepheid variable discovery was enabled, a discovery that allowed Hubble to relate galactic redshift to their distance from the Earth, a relationship now known as Hubble's law.
Joining Leavitt as a member of the Harvard College Observatory computers in 1896 was Annie Jump Cannon (1863-1941), who had received a physics degree from Wellesley College in 1884. She had been encouraged in her scientific studies by her mother, and she became a Wellesley College student of Sarah Frances Whiting (1847-1927), one of the earliest woman physicists in the United States. Cannon was the valedictorian of her class at Wellesley College.
After graduation, Cannon learned photography, but she didn't seek any professional position until her mother died in 1894. That year, Whiting hired her as a junior physics teacher at Wellesley. While teaching, Cannon learned spectroscopy, and she started studies for an MA degree that was finally completed in 1907. In 1896, physicist and astronomer, Edward C. Pickering, hired her as his assistant at the Harvard College Observatory.
Cannon's assigned task at Harvard was to catalog variable stars and classify the spectra of stars in the southern celestial hemisphere. In 1911, her position was advanced to curator of observational photographs, and she embarked on a forty year project to spectrally classify stars down to ninth magnitude.
The result of this study was the nine volumes of the Henry Draper Catalogue, named after an amateur astronomer in whose memory the project was funded. This catalog, published from 1918-1924, lists nearly a quarter of a million stars, assigning them to the O, B, A, F, G, K and M letter classification. The catalog was extended over the years, classifying many more stars.
People with disabilities have made important contributions to science. We have the example of Stephen Hawking. Annie Cannon was doubly disabled, being nearly deaf, and also (for that time) a woman. Her deafness is presumed to have been caused by her contracting scarlet fever. It wasn't until 1938, many years after the Draper Catalogue, that she was promoted from astronomical assistant to astronomer, at age 74.
Aside from classifying stars, Cannon discovered 300 variable stars and five novas. Her system of stellar classification, with a few additional members (my R, N, and S stars) and other tweaks is still used by today's astronomers. Canon was the first woman officer of the American Astronomical Society. The Annie Jump Cannon Award is given annually to a distinguished North American woman astronomer.
- Baby Names for the 2010 Decade, United States Social Security Administration Web Site.
- Dan Malerbo, "Let's talk about science: development of star classification," Pittsburgh Post-Gazette, May 19, 2016.
- Annie J. Cannon, "Sarah Frances Whiting," Science, vol. 66, no. 1714 (November 4, 1927), pp. 417-418, DOI: 10.1126/science.66.1714.417.
Permanent Link to this article
Linked Keywords: Science; tradition; traditional; male-dominated; profession; scientist; engineer; history; misogyny; misogynist; baby boomer; my generation; mnemonic; electronic component color code; printing; pitch; numeric character; resistance; capacitance; inductance; color; black; brown; red; orange; yellow; green; blue; violet; grey; gray; white; laboratory; lab; Bad boys rape our young girls but violet gives willingly; girl; decade; resistor; capacitor; inductor; Inkscape; star; spectrum; spectral; astronomer; stellar classification; O-type star; B-type main-sequence star; A-type main-sequence star; F-type main-sequence star; G-type main-sequence star; K-type main-sequence star; stellar classification M; Sun; carbon star R, N; S-type star; Caroline Herschel; sibling; sister; astronomer; William Herschel; planet; Uranus; polish; reflecting telescope mirror; Gold Medal of the Royal Astronomical Society; Royal Astronomical Society; salary; George III of the United Kingdom; King George III; lithograph; Wellcome Library; Wikimedia Commons; Edwin Hubble; metric expansion of space; expanding universe; American; Henrietta Swan Leavitt (1868-1921); conjecture; proportionality; period; luminosity; Cepheid variable star; star; Delta Cephei; employer; colleague; Edward C. Pickering; Periods of 25 Variable Stars in the Small Magellanic Cloud; Harvard College Observatory Circular; straight line; point; maxima and minima; Earth; emission of light; Radcliffe College; Harvard College Observatory; photographic plate; data; galactic redshift; Hubble's law; A woman's work is never done; American Institute of Physics; Annie Jump Cannon (1863-1941); physics; academic degree; Wellesley College; scientific; mother; Sarah Frances Whiting (1847-1927); physicist; United States; valedictorian; Wilhelm Röntgen; X-rays; Crookes tube; radiography; radiograph; coin; handbag; purse; bone; flesh; graduation; photography; spectroscopy; Master of Arts; MA degree; southern celestial hemisphere; curator; ninth magnitude; volume; Henry Draper Catalogue; amateur astronomy; amateur astronomer; New York World-Telegram and the Sun Newspaper; disability; Stephen Hawking; hearing loss; deaf; scarlet fever; nova; American Astronomical Society; Annie Jump Cannon Award; North America; Cannon Crater; Moon; Lunar Orbiter 4.
Latest Books by Dev Gualtieri
Thanks to Cory Doctorow of BoingBoing for his favorable review of Secret Codes!
Blog Article Directory on a Single Page
- J. Robert Oppenheimer and Black Holes - April 24, 2017
- Modeling Leaf Mass - April 20, 2017
- Easter, Chicks and Eggs - April 13, 2017
- You, Robot - April 10, 2017
- Collisions - April 6, 2017
- Eugene Garfield (1925-2017) - April 3, 2017
- Old Fossils - March 30, 2017
- Levitation - March 27, 2017
- Soybean Graphene - March 23, 2017
- Income Inequality and Geometrical Frustration - March 20, 2017
- Wireless Power - March 16, 2017
- Trilobite Sex - March 13, 2017
- Freezing, Outside-In - March 9, 2017
- Ammonia Synthesis - March 6, 2017
- High Altitude Radiation - March 2, 2017
- C.N. Yang - February 27, 2017
- VOC Detection with Nanocrystals - February 23, 2017
- Molecular Fountains - February 20, 2017
- Jet Lag - February 16, 2017
- Highly Flexible Conductors - February 13, 2017
- Graphene Friction - February 9, 2017
- Dynamic Range - February 6, 2017
- Robert Boyle's To-Do List for Science - February 2, 2017
- Nanowire Ink - January 30, 2017
- Random Triangles - January 26, 2017
- Torricelli's law - January 23, 2017
- Magnetic Memory - January 19, 2017
- Graphene Putty - January 16, 2017
- Seahorse Genome - January 12, 2017
- Infinite c - January 9, 2017
- 150 Years of Transatlantic Telegraphy - January 5, 2017
- Cold Work on the Nanoscale - January 2, 2017
- Holidays 2016 - December 22, 2016
- Ballistics - December 19, 2016
- Salted Frogs - December 15, 2016
- Negative Thermal Expansion - December 12, 2016
- Verbal Cues and Stereotypes - December 8, 2016
- Capacitance Sensing - December 5, 2016
- Gallium Nitride Tribology - December 1, 2016
- Lunar Origin - November 27, 2016
- Pumpkin Propagation - November 24, 2016
- Math Anxiety - November 21, 2016
- Borophene - November 17, 2016
- Forced Innovation - November 14, 2016
- Combating Glare - November 10, 2016
- Solar Tilt and Planet Nine - November 7, 2016
- The Proton Size Problem - November 3, 2016
- Coffee Acoustics and Espresso Foam - October 31, 2016
- SnIP - An Inorganic Double Helix - October 27, 2016
- Seymour Papert (1928-2016) - October 24, 2016
- Mapping the Milky Way - October 20, 2016
- Electromagnetic Shielding - October 17, 2016
- The Lunacy of the Cows - October 13, 2016
- Random Coprimes and Pi - October 10, 2016
- James Cronin (1931-2016) - October 6, 2016
- The Ubiquitous Helix - October 3, 2016
- The Five-Second Rule - September 29, 2016
- Resistor Networks - September 26, 2016
- Brown Dwarfs - September 22, 2016
- Intrusion Rheology - September 19, 2016
- Falsifiability - September 15, 2016
- Fifth Force - September 12, 2016
- Renal Crystal Growth - September 8, 2016
- The Normality of Pi - September 5, 2016
- Metering Electrical Power - September 1, 2016
Deep Archive 2006-2008