Henrietta Hill Swope, American astronomer and academic (b. 1902)

Henrietta Hill Swope (October 26, 1902 – November 24, 1980) was an American

astronomer who studied variable stars. In particular, she measured the period-luminosity relation for Cepheid stars, which are bright variable stars whose periods of variability relate directly to their intrinsic luminosities. Their measured periods can therefore be related to their distances and used to measure the size of the Milky Way and distances to other galaxies.