Extraordinary Women Scientists....Chapter 1

Annie Jump Cannon: astronomer, 1863-1941.

It was young Annie Jump Cannon's mother who first introduced her to the stars. From the attic in her home in Dover, Delaware, Annie and her mother enjoyed gazing at the night sky. Using an old astronomy textbook, they tried to identify these celestial bodies. Annie memorized the constellations, observed how the positions of the stars changed from season to season, and recorded her notes by candlelight. Thus, her fascination with the heavens began, a passion that eventually led her to the Harvard College Observatory, where she created one of the greatest catalogs of stars ever produced. Annie did this work in the world of silence, because by the time she became a Harvard astronomer, she was almost completely deaf.

When Annie Jump Cannon was born on December 11, 1863, the United States was embroiled in a civil war. She grew up in a large household with six other children. In 1880, Annie enrolled at Wellesley College in Massachusetts, and became influenced by Sara F. Whiting, one of the first women professors of physics and astronomy. Whiting introduced Cannon to spectroscopy; a technique that analyzes light coming from the stars, with the use of a prism that separates the light into its various colors. By this time, astronomers had concluded that spectroscopy provided a wonderful tool for learning, because each chemical element heated by the energy a star emits, gives off its own unique pattern of light.

After graduating, Cannon returned to her family home. Although vivacious and popular, she showed no interest in settling down to married life. Instead, she embarked for Europe with her "Kamerette", one of the first box cameras invented. Her experience with photography would later prove invaluable to her work in astronomy.

In 1893 Annie returned to Wellesley to work on a master's degree, and in 1896, she joined astronomy professors Edward C. Pickering and Williamina Fleming on the staff of Harvard College Observatory.
Pickering and Fleming had been engaged in a massive project to photograph and analyze spectra of stars. Based on this work, Cannon developed the Harvard System of Spectral Classification, using Roman numerals to rank them from the hottest white and blue to the coolest red. She found that almost all stars in the visible sky fit these groupings.

During her long career, Annie received many honors, including an honorary Doctor of Science degree from Oxford University, the first awarded to a woman. Perhaps her greatest achievement was the creation of a huge nine-volume work called, The Henry Draper Catalogue, named after a pioneer in stellar spectroscopy.
Her system is still used by astronomers today.
 From Extraordinary Women Scientists by Darlene R. Stille.