AST-781beginner

Cepheids, RR Lyrae & Standard Candles: Foundations

Cepheid and RR Lyrae variables are pulsating stars whose luminosities can be inferred from characteristic light-curve properties. Cepheids calibrate nearby galaxies and Type Ia supernova hosts; RR Lyrae stars map globular clusters, the Galactic halo, and nearby old populations.

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Cepheids, RR Lyrae & Standard Candles: Foundations

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AST-780Radar Ranging & Stellar Parallax: Advanced Connections→

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AST-782Cepheids, RR Lyrae & Standard Candles: Structures & Vocabulary→

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Cepheid and RR Lyrae variables are pulsating stars whose luminosities can be inferred from characteristic light-curve properties.

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Partial ionization zones in stellar envelopes can act as heat engines: opacity changes trap and release energy during expansion and contraction, sustaining radial pulsation.

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