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This glossary covers words that you will come across on this website.

Cepheid Variable

A Cepheid is a member of a particular class of variable stars. It is usually a Yellow Giant or Supergiant that is pulasting. The relationship between a Cepheid variable's luminosity and variability period is quite precise. Cepheids are viable as the standard candle, meaning that they are the foundation of the Extragalactic Distance Scale.