Annie Jump Cannon

Annie Jump Cannon was born on December 11th, 1863, in Dover, Delaware, U.S. She was an American astronomer who specialized in the classification of stellar spectra.

Cannon was the eldest daughter of Wilson Cannon ( A Delaware state senator), and Mary Jump, Cannon was inspired by her mother to pursue science. Canon would often open the trapdoor to the roof so they could watch the stars.

Cannon attended Wilmington Conference Academy, and then went to Wellesley College, with encouragement from her mother to study science and math. Wellesley College was one of the so-called “seven sisters” colleges for women. While there, Cannon contracted scarlet fever, which destroyed much of her hearing.

Still, at Wellesley she had the privilege to study under a pioneer in the field, Sarah Frances Whiting. Cannon would later write Whiting’s biography for the Popular Astronomy journal. And in 1884, Cannon graduated from Wellesley as the valedictorian of her class.

When Cannon returned home to Delaware, she found few opportunities available to her, both because she was a woman and because of her partial deafness. For years after she traveled and dabbled in photography and music.  In 1893, her published book of photography was used as a souvenir for the Chicago World Fair.

Finally, the death of her mother in 1894, Cannon returned to science, returning back to Wellesley College and working as a junior physics teacher while taking graduate classes. Cannon also decided to enroll as a “special student” at Radcliffe College to study astronomy. Radcliffe was the women’s college connected to the all-male Harvard College.

Two years into her tenure at Radcliffe, Cannon was hired to work at the Harvard College Observatory under Edward C. Pickering in 1895.

In 1895, Cannon participated in the first X-ray experiments in the country. In addition, she also became a part of a group of women at the observatory called “Pickering’s Women” / “computers”.  Joining William P.S Fleming and Antonia Maury, she devoted her energies to Pickering’s ambitious project, which began in 1885; recording, classifying and cataloging the spectra of all stars, even down to those of the ninth magnitude.

Under the direction of Pickering, the women worked to complete the Henry Draper Catalogue of stars by classifying all the stars in the sky. Unfortunately, these women were underpaid, and earned as little as 50 cents an hour. Despite this, Cannon did not let this stop her from making major scientific discoveries.

Prior to receiving her master’s degree from Wellesley College in 1907, Cannon had already published her first catalog of stars in 1901, where she developed a new system that classified stars mainly based on temperature. This became known as the Harvard spectral classification system, Cannon’s sequence is still studied by astronomers today. By using the mnemonic device “Oh! Be A Fine Girl — Kiss Me!” (OBAFGKM), astronomers are able to organize stars according to their characteristics.

Cannon’s remarkable work did not stop there. In 1911, Cannon succeeded Fleming as curator of astronomical photographs at Harvard’s observatory. She was known for her speed at classifying stars and was credited with classifying 5,000 stars per month from 1911 to 1915. She continued on to catalogue about 350,000 stars over her lifetime.

In 1921, Cannon became the first woman to receive a Doctor of Astronomy Degree from Groningen University. A year later, the International Astronomical Union adopted Cannon’s methods as the official spectral classification system.

After 1924 she extended her work, cataloging tens of thousands of additional stars down to the 11th magnitude for the second volume of Henry Draper Extension (1925, 1949). The work was an invaluable contribution to astronomy, bearing strongly on countless other problems and areas of research and exerting major influence on the evolution of the science of astronomy from one of mere observation to one of great theoretical and philosophical content. In the course of her work, Cannon also discovered some 200 variable stars and 5 novae.

In addition to her scientific work, Cannon also worked for women’s rights. She was dedicated to fighting for women’s suffrage and was a member of the National Women’s party.

In 1923, Cannon was voted one of the 12 greatest living women in America by the National League of Women Voters. Shortly after, she became the first woman to receive an honorary degree from Oxford University (1925) and the first woman to be awarded the Henry Draper Medal of honor from the National Academy of Sciences (1931)

After decades of hard work, Cannon was finally appointed a permanent faculty position at the Harvard College Observatory in 1938. Although, two years later she officially retired. (1940)

Cannon would go on to work in the observatory all the way up until her death the following year. Annie Jump Cannon died in April of 1941, in Cambridge, Massachusetts,. At 77 years old.