William Wilson Morgan

William Wilson Morgan (January 3, 1906 – June 21, 1994) was an American astronomer and astrophysicist.[1] The principal theme in Morgan's work was stellar and galaxy classification. He is also known for helping prove the existence of spiral arms in our galaxy. In addition to his scientific achievements he served as professor and astronomy director for the University of Chicago's Yerkes Observatory in Wisconsin and was the managing editor for George Hale's Astrophysical Journal.-Wikipedia