Astronomers who helped make it great

Yerkes Observatory owes its prominence in the astronomical community not so much to its great telescope, beautiful building or exceptional library, but to the extraordinary people who have been students, faculty or staff there during its 100-year history.

Until the 1960s, the University's astronomy department was based at Yerkes, and students who received their degrees through the department spent virtually all of their years of University study there.

Edwin Hubble (Ph.D.'17) went on to discover the expanding nature of the Universe, using Hale's telescopes at Palomar. The Hubble Space Telescope bears his name.

George Ritchey, an optician who worked at Yerkes during the early years, designed a 24-inch mirrored telescope (now on display at the Smithsonian Institution) that made it possible for reflecting telescopes to revolutionize astronomy. The most popular design for these types of telescopes today is named after him.

Otto Struve (Ph.D.'23) later returned to the observatory in 1932 as Director. He is credited with reviving a department that languished after Hale's departure for Mount Wilson in 1903 and with assembling one of the world's finest collections of theoretical and observational astrophysicists. Under his leadership, and his legacy, Yerkes and its galaxy of superstars flourished through the 1960s.

One of Struve's recruits was a young theorist named Subrahmanyan Chandrasekhar. He accepted an appointment at Yerkes in 1935, and remained on the faculty of the University until his death in 1995. Chandrasekhar's contributions to the field are innumerable, and he was awarded the Nobel Prize in Physics in 1983 for his theoretical work on the structure of stars made out of ultra-dense matter. Chandrasekhar's unsurpassed brilliance served as a "great attractor," a nucleus around which a stellar theoretical astrophysics group was assembled at Chicago.

William Wilson Morgan (Ph.D.'31) a distinguished observer who spent his entire scientific career at Yerkes Observatory, until his death at age 88 in 1994, discovered the spiral arms of the Milky Way Galaxy and compiled an unsurpassed atlas of stellar spectra.

Donald Osterbrock (Ph.D.'52) studied with both Chandrasekhar, the theorist, and Morgan, the observer. He carried the influence of both in his work, and later became director of Lick Observatory. Osterbrock has written several books on the history of astronomy, including his most recent, Yerkes Observatory 1892-1950, published by the University of Chicago Press.

Jeremiah Ostriker (Ph.D.'64) was a student of Chandrasekhar's who has spent most of his career studying theoretical astrophysics and cosmology at Princeton. When Hugo Sonnenschein left Princeton to become President of the University of Chicago in 1993, Ostriker succeeded him as Provost at Princeton.

Other scientists whose careers were nurtured at Yerkes included such luminary astronomers as Gerard Kuiper, an outstanding planetary astrophysicist for whom the Kuiper Airborne Observatory is named; Bengt Stroemgren, a leader in the study of elemental abundances in stars; Louis Henyey (Ph.D.'37), a brilliant theorist; Jesse Greenstein, who participated in the discovery of quasars; Gerhard Herzberg, who would later win the Nobel Prize in Chemistry; and Carl Sagan (Ph.D.'60), who popularized astronomy for millions of Americans.