Sarah Lee Lippincott (1920–2019)

Sarah Lee Lippincott died on Friday the 28^th of February, 2019.

Sarah Lee Lippincott was born on October 26, 1920, in Philadelphia. She earned a Bachelor of Arts degree in 1942 from the University of Pennsylvania and a Master of Arts degree from Swarthmore College in 1950. She was awarded an honorary Doctorate of Science from Villanova University in 1973. Her entire career involved work at Sproul Observatory and Swarthmore College, first as resident assistant astronomer (1942–1951), resident associate astronomer (1952–1976), lecturer (1961–1976), director of the observatory (1972–1981) and professor (1977–1981).

Sproul Observatory was dedicated to astrometry, the careful measurement of the positions of celestial objects (primarily stars). The resultant stellar parallaxes and proper motions constitute basic astronomical data relevant to the cosmological distance scale and the dynamics of stars in the Milky Way galaxy. The observatory’s workhorse instrument was a long focus 24-inch diameter refracting telescope built in 1911 by the John A. Brashear Company of Pittsburgh, Pennsylvania. Other similar American refracting telescopes of that era include the U. S. Naval Observatory 26-inch (1873), the 26-inch refractor of University of Virginia’s Leander McCormick Observatory (1885), the Lick Observatory 36-inch (1888), and the Yerkes Observatory 40-inch (1897).

Along with her predecessor as Sproul Observatory director, Peter van de Kamp, Lippincott sought to discover low mass companions to nearby stars, what we would call today brown dwarfs and extrasolar planets. In 1951 she and van de Kamp published a paper on a possible 0.01 solar mass companion of the star Lalande 21185. This result, and van de Kamp’s evidence for planetary companions of Barnard’s Star are now regarded as spurious, and we understand the reason why. The primary objective lens of the Sproul refractor was semi-regularly removed from the telescope and its cell for cleaning, leading to small but significant systematic errors in the measurements of stellar positions. It is fair to say that their efforts were beyond the scope of the technology of the time (photographic plates). But these efforts motivated the technological progress of the 1980s and 1990s, leading to an explosion of discoveries of extrasolar planets and a whole new major area of exciting astronomical science.

As an educator, Lippincott was a mentor to many Swarthmore undergraduates. Probably the most notable of them was Sandra Faber, who would eventually be awarded the Presidential Medal of Science (2012).

Lippincott’s first husband was Dave Garroway (1913–1982), the first host of NBC’s Today show and a keen amateur astronomer. They met on a tour of observatories in the Soviet Union that she was hosting. After he died by suicide, she helped establish a laboratory for the study of depression at the University of Pennsylvania.

Lippincott died of natural causes in her 99^th year. She was predeceased by her second husband Christian Zimmerman and survived by the children of her late husbands and extended family.