Left pointing hand navigation decoration Return to “Telescopes from the Ground Up” Left pointing hand navigation decoration
Telescopes from the Ground Up
Portrait of Annie Jump Cannon. Courtesy Wellesley College Archives

In the 1870s, the director of the Harvard Observatory, Edward C. Pickering, hired several women, called “calculators,” to perform calculations to classify and catalog stars for fifty cents an hour. One of those women was Annie Jump Cannon.

Cannon, a Delaware native, became interested in astronomy as a young girl, when her mother taught her the constellations. When she was 17, she attended Wellesley College in Massachusetts. She majored in physics, but studied astronomy as well. She used the campus telescope to observe the stars and learned much from studying their light.

In 1896, Cannon joined the Harvard staff as a calculator. She is known as the “census taker of the stars” and created the classification system for stars that is still used today.

Cannon classified over 300,000 stars. She was known for her speed in classifying stars and her extraordinary ability to draw distinctions in the photographs of stellar spectra. In 1925, she received an honorary doctorate degree from Oxford University, a first for women. Her published work, the nine-volume Henry Draper Catalogue of star spectra and positions, continues to be used internationally by astronomers.

Return to “Telescopes from the Ground Up”