Science
Henrietta Swan Leavitt
Astronomer discovering the variable-star period–brightness relation
Also known as Henrietta S. Leavitt
Photograph · Image credit
Who they are
Henrietta Swan Leavitt measured variable stars in the Small Magellanic Cloud and established a relation between their periods and brightnesses. The common-distance setting made intrinsic differences visible. Her 1912 analysis, issued by Edward Pickering, became a foundation for later calibrated stellar distances and Hubble’s evidence for galaxies beyond the Milky Way.
She supplies a crucial observational step in the timeline’s expansion of the measured universe.
Selected contributions
Selected works
Academic paper · 1912
Periods of 25 Variable Stars in the Small Magellanic Cloud
Leavitt’s analysis relates the periods and brightnesses of 25 Small Magellanic Cloud variables, using their roughly common distance. Pickering issued the circular, whose opening credits her preparation; an absolute calibration remained to be supplied.
Reading scope & citation
Reuses documented prior inspection: First and last pages visually inspected as screenshots; the middle table/graph page not separately audited.
In the timeline
Biography sources & portrait credit
- Periods of 25 Variable Stars in the Small Magellanic Cloud, Harvard College Observatory Circular 173 ↗Harvard College Observatory; scan hosted by University of Sheffield
- Carnegie Science celebrates Edwin Hubble’s discovery of the universe ↗Carnegie Science
Portrait credit
Unknown photographer. Public domain (Commons file-specific copyright declaration). Via Wikimedia Commons.
Photograph. Cropped to 4:5, resized to 320 × 400 and converted to WebP.
Image source & identification ↗ · Public domain (Commons file-specific copyright declaration) ↗
