Technique · The Cosmic Distance Ladder
The Cepheid Distance Scale
Cepheid variable stars pulse with a period that depends on their true luminosity — Henrietta Leavitt's discovery. Measure the period, know the luminosity, and the apparent brightness gives the distance. Cepheids calibrated the scale of the galaxy and beyond.
The Cosmic Distance LadderMeasures: Distance from a Cepheid's pulsation
Highlights
- ›Leavitt's law: a Cepheid's period reveals its luminosity
Builds on
Knowledge connections
- Member of groupThe Cosmic Distance Ladder
- Associated withThe Cepheid Period–Luminosity Relation
- Associated withSH0ES
Sources
The primary and reference sources this topic draws on.
- NASANational Aeronautics and Space Administration
Mission data, planetary science, space telescopes, and public-domain imagery.
Most NASA-produced imagery is in the public domain; individual items are checked for usage terms before publication.