Henrietta Swan Leavitt

American astronomer (1868–1921)

Henrietta Swan Leavitt (July 4, 1868 – December 12, 1921) was an American astronomer. Her discovery of how to effectively measure vast astronomical distances led to a shift in the understanding of the scale and nature of the universe. A graduate of Radcliffe College, she worked at the Harvard College Observatory as a human computer, tasked with measuring photographic plates to catalog the positions and brightness of stars.

From Wikipedia, under CC BY-SA. More on occurri.