Annie Jump Cannon

by Dana Kester-McCabe

Dover native Annie Jump Cannon was known as the "Census Taker" of the stars.

A few months ago a friend of mine sent out an email to alert the ladies in my book club that Google was honoring a distinguished Delmarva native in one of their Google Doodle's. It was the birthday of Annie Jump Cannon. I had never heard of her before, but since then I have enjoyed finding out more about her. There is even a song dedicated to her written by one Lynda Williams, also known as the Physics Chanteuse.

Annie Jump Cannon was born on December 11, 1863, in Dover, Delaware. Annie was the middle child of eight. There were four before her from her father's first marriage and she and three others followed from his marriage to her mother Mary Jump. Her father was a Democratic State Senator who broke from his party to vote against secession at the onset of the Civil War. Aside from an active political life, he was a successful merchant and ship builder. Her mother Mary was a bright woman who encouraged her children's curiosity.

The Cannon's built a makeshift observatory in their attic where, at a young age Annie recorded her observations of the stars by candle light. Annie must have been an extremely inquisitive and precocious child. Because her family that could afford a quality education for her, she attended Wilmington Conference Academy which is now Wesley College in Dover and then went on to Wellesley College where she earned her bachelor's degree in physics in 1884.

Annie was a beautiful girl and a gifted pianist. Though her biographical papers record a thriving social life, it does not mention any special beaux. She was an early photographer when photography was not yet a widespread hobby. She traveled abroad and her pictures of Spain were "greatly admired". After college she returned home to Dover where she stayed for almost a decade until her mother's passing. Then she returned to her studies in at Wellesley and committed to her true calling: astrophysics.

In 1896, she was hired to be part of the team known as "Pickering's Women," women hired by Harvard College Observatory director Edward Pickering. Though she probably made considerably less than a dollar an hour this was a major breakthrough for women scientists. They were research scientists who were essentially human computers recording and analyzing data. At the time there was a controversy about the best way to classify stars. Should it be for their size, their brilliance, or their color? Annie pioneered a combined system. "Pickering's Women" had been using the alphabet to catalog stars in classes based on their temperature. Other characteristics of the stars began to complicate things until finally the alphabet system was not working at all. So Annie organized the data from those stars grouped in the classes O-B-A-F-G-K and M. They came up with this mnemonic remember the order: Oh Be A Fine Girl Kiss Me.

On May 9, 1922, the International Astronomical Union passed a resolution to formally adopt Cannon's stellar classification system, and with only minor changes, it is still being used for classification today. This is the basis for the system still used by astronomers today.

Annie's life was not all work and not without its challenges. Something caused Annie to go deaf. One source claims it was caused by exposure to cold as a college student. Another posits that it was the result of scarlet fever which she caught while visiting Spain in 1893 to photograph an eclipse. No matter. When she lost her hearing she appears to have been undaunted. She continued her research and travelled around the world taking pictures of stellar spectra. She was also quite popular on the lecture circuit. She was known to be a charming and engaging speaker who was clearly passionate about the stars.

Annie biographical papers indicate that she enjoyed cooking and entertaining. She called her home not far from Harvard's observatory the "Star Cottage." She loved entertaining the children of her co-workers. Every year she held an Easter egg rolling contest for them. She was also a suffragette and a progressive Republican, who expressed frustration about the apathy of some women for voting.

Annie lived and worked most of her life in Massachusetts. But she was returned to her Dover roots when she died in 1941 to be buried there at Lakeside Cemetery. Today she remains well loved in scientific circles for her accomplishments. She has been nicknamed "The Census Taker of the Sky", because she classified almost a quarter of a million stars, more than anyone else has ever done - including 300 she personally discovered.

She was the first woman elected as officer of the American Astronomical Society. A crater on the moon and an asteroid are named Cannon after her. In 1929 she was listed as one of twelve "greatest living women" by the National League of Women Voters. Cannon Hall, a residence dormitory at the University of Delaware, is named in her honor. I could go on but I think you get the picture.

After receiving one particularly generous award Annie set up her own award: The Annie Jump Cannon Award in Astronomy which is awarded annually by the American Astronomical Society (AAS) to a woman resident of North America for distinguished contributions to astronomy.

Find out more:
Annie Jump Cannon - Produced and Performed by Lynda Williams
Sisters of the Sun