A

David

Darling

beat Cepheid

A beat Cepheid is a Cepheid variable in which two or more nearly equal periods of variability pass into and out of phase with each other, producing a "beat." Also known as double-mode Cepheids, such stars account for nearly half of all Cepheids with periods of 2 to 4 days. Beat periods are typically about 2 hours.