Pulsating variable stars
type: Concept
narrower: Cepheid variable stars

Young disk Cepheid variable stars
type: Concept
broader: Cepheid variable stars

Anomalous Cepheid variable stars
type: Concept
broader: Cepheid variable stars

Type II Cepheid variable stars
type: Concept
broader: Cepheid variable stars

Cepheid variable stars
type: Concept
contributor: AAS Frey.Katie
contributor: AAS Frey.Katie Admin
modified: 2020-10-26T19:38:31.65Z
modified: 2022-06-24T15:29:40.997Z
alternative label: Bump cepheid
alternative label: Cepheid variables
alternative label: Cepheid stars
alternative label: Classical Cepheid
alternative label: Cepheids
broader: Pulsating variable stars
definition: A class of luminous, yellow supergiants that are pulsating variables and whose period of variation is a function of their luminosity. These stars expand and contract at extremely regular periods, in the range 1-50 days. Their highest brightness and surface temperature occur when their expansion velocity is greatest. Similarly, their minima in brightness and temperature occur when they are in the contraction phase. The longer the period, the more luminous the star. The process that drives the pulsation of Cepheid variables is the kappa mechanism. In fact, Cepheids provide one of the most powerful tools for measuring distances to other galaxies (period-luminosity relation). However, this method is limited to the distance of the Virgo cluster of galaxies (15-20 Mpc) even with the HST or the largest ground-based telescopes. One particularly special Cepheid is the North Star, Polaris.
narrower: Type II Cepheid variable stars
narrower: Anomalous Cepheid variable stars
narrower: Young disk Cepheid variable stars
narrower: Delta Cepheid variable stars
narrower: Double-mode Cepheid variable stars

Delta Cepheid variable stars
type: Concept
broader: Cepheid variable stars

Double-mode Cepheid variable stars
type: Concept
broader: Cepheid variable stars