John Charles Duncan

John Charles Duncan
As Wellesley College Professor of Astronomy in 1932
Born(1882-02-08)February 8, 1882
DiedSeptember 10, 1967(1967-09-10) (aged 85)
Alma materIndiana University, Bloomington; University of California, Berkeley, California
Scientific career
FieldsAstronomy
InstitutionsUniversity of Arizona
Harvard University
Radcliffe College
Wellesley College
ThesisThe Orbits of the Cepheid Variables Y Sagittarii and RT Aurigae; with a Discussion of the Possible Causes of this Type of Stellar Variation (1909)
Doctoral advisorWilliam Wallace Campbell
Signature

John Charles Duncan (February 8, 1882 – September 10, 1967) was an American astronomer. His work spanned astronomy’s transition from a focus on observation and location measurement to astrophysics. He was well known for his basic college textbook "Astronomy", in widespread use for 30 years after its first publication in 1926. His career was a fruitful combination of research and teaching at major observatories, in his own classrooms and through his textbook. Duncan was the first to note the expansion of the Crab Nebula and from that determine the approximate year of its creation, discovered variable stars in what were soon found to be distant galaxies, and describe the nebular structures now known as the Pillars of Creation.