Annie Jump Cannon, shown at her Harvard College Observatory office, was one of the first American women astronomers. During her 40-year career, she cataloged more than 300,000 stars based on their spectra. From that work, she devised the basic stellar classification system that is still used today. [Smithsonian Institution]
Like most professions in the late 19th century, astronomy wasn’t just male dominated, it was pretty much men-only. In fact, one of the few places where women were contributing to astronomy at all was Harvard College Observatory. They weren’t actual astronomers, though — they spent their time classifying photographic plates. But some of them became astronomers, and made some of the most important scientific contributions of the early 20th century.
One of those women was Annie Jump Cannon. She was born 150 years ago tomorrow in Dover, Delaware. Her father was a shipbuilder and state senator. But it was her mother who instilled Annie’s interest in the stars.
Despite a childhood bout of scarlet fever that left her almost completely deaf, Cannon earned a degree in physics and astronomy from Wellesley College. In 1892 she traveled to Europe to photograph a solar eclipse, and a few years later she returned to Wellesley to pursue a graduate degree.
Shortly after that, Cannon enrolled at Radcliffe Women’s College at Harvard. She learned spectroscopy, which breaks a star’s light into its individual wavelengths or colors, revealing the star’s composition, motion, and much more.
Cannon soon put that knowledge to work. Harvard College Observatory hired her as a “computer.” She spent six days a week sorting stars by their spectra — a task that eventually led her to create a new classification scheme for the stars. More about that tomorrow.
Script by Damond Benningfield, Copyright 2013
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