Henrietta Swan Leavitt

Ejnar Hertzsprung and the Hertzsprung-Russell Diagram

8. October 2022 Tabea Tietz

On October 8, 1873, Danish chemist and astronomer Ejnar Hertzsprung was born. Together with Henry Norris Russell, Hertzsprung developed the Hertzsprung–Russell diagram, a scatter graph of stars showing the relationship between the stars‘ absolute magnitudes or luminosities versus their spectral classifications or effective temperatures, which has become fundamental to the study of stellar evolution. Ejnar Hertzsprung – Early Years Ejnar Hertzsprung was probably not formally educated, but studied in technological colleges in Denmark…

astronomy

Helen Swayer Hogg and the Globular Clusters

1. August 2022 Harald Sack

On August 1, 1905, American-Canadian astronomer Helen Sawyer Hogg was born. Hogg is noted for pioneering research into globular clusters (stars with cyclical changes of brightness found within huge, dense conglomerations of stars located in the outer halo of the Milky Way galaxy) and variable stars. She was the first female president of several astronomical organizations and a notable woman of science in a time when many universities would not award scientific…

astronomy

Harlow Shapley and the Size of the Milky Way

2. November 2021 Tabea Tietz

On November 2, 1885, American astronomer Harlow Shapley was born. Shapley is best know for having correctly estimated the size of the Milky Way Galaxy and the sun’s position within it. Harlow Shapley – Early Years Harlow Shapley was born in Nashville, Missouri and dropped out of school after fifth grade. However, later on he managed to return to school and complete a six-year high school program in only two years. At…

astronomy