pulsation theory

astronomy

Also known as: Eddington theory

Written by

The Information Architects of Encyclopaedia Britannica

Last updated

July 13, 2026

Quick Summary

The pulsation theory in astronomy explains the variability of certain stars, such as Cepheid variables, by proposing that these stars expand and contract rhythmically. This expansion and contraction, or pulsation, causes their total energy output to fluctuate over time.12

These intrinsically variable stars are crucial for astronomers because they often represent critical, short-lived phases in a star's evolution. Studying their light and spectral characteristics can offer insights into stellar life histories. Certain types of pulsating stars, like Cepheids, are particularly important for determining the distances to remote stellar systems, including other galaxies, due to their predictable period-luminosity relationship.2

Summary created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

4 Britannica Sources

Ask Britannica AI about this topic

Britannica doesn't have a full article on this topic, so we've curated a list of our relevant coverage.

star
Pulsating stars
The pulsation theory was first proposed as a possible explanation as early as 1879, was applied to Cepheids in 1914, and was further developed by Arthur Eddington in 1917–18. Eddington found that if stars have roughly the same kind of internal structure, then the period multiplied…
Read More
The pulsation theory was first proposed as a possible explanation as early as 1879, was applied to Cepheids in 1914, and was further developed by Arthur Eddington in 1917–18. Eddington found that if stars have roughly the same kind of internal structure, then the period multiplied…
Read More