Annie Jump Cannon

Annie Jump Cannon devised the stellar classification scheme still used today, ordering stars by temperature into the sequence O B A F G K M. Working at Harvard with extraordinary speed and accuracy, she classified the spectra of hundreds of thousands of stars for the Henry Draper Catalogue, turning the chaos of stellar spectra into an ordered system.

• Created the Harvard stellar spectral classification (OBAFGKM)
• Classified the spectra of over 350,000 stars
• Led the compilation of the Henry Draper Catalogue

• Harvard Spectral Classification1901 CE
• Henry Draper Catalogue1924 CE

• StudiesThe Milky Way
• Part ofModern Astronomy
• Collaborated withEdward Charles Pickering
• IntroducedHenry Draper Catalogue
• IntroducedHarvard Spectral Classification