Henrietta Swan Leavitt Pint Glass
One left! Back in 1893, Henrietta Swan Leavitt, was not allowed to operate a telescope at the Harvard College Observatory. However, her fascination for the luminosity of Cepheid variable stars, and her determination to look at the plates of 1,777 variable stars, identify them, and measure their brightness, let her to discover the relation between the luminosity and the period of Cepheid variable stars.