Henry Draper system
râžmân-e Henry Draper
Fr.: système de Henry Draper
A catalog of stars in which every star is classified by its stellar spectrum. This system is named for the astronomer Henry Draper, but was cataloged by Annie J. Cannon (225,300 stars), and later extended by Margaret W. Mayall.
Henry Draper (1837-1882), an American pioneer of astronomical spectroscopy who established the observing techniques and program for the work that would bear his name when published, seven years after his early death; → system.