Explore: Cepheid Variables

distance to classical Cepheid variables in the Andromeda Galaxy, until then known as the "Andromeda Nebula" and showed that those variables were not members

about 2 magnitudes. Classical Cepheids are also known as Population I Cepheids, Type I Cepheids, and Delta Cepheid variables. There exists a well-defined

W Virginis variables are a subclass of Type II Cepheids which exhibit pulsation periods between 10–20 days, and are of spectral class F6 – K2. They were

pulsating variable stars with their pulsation period. The best-known relation is the direct proportionality law holding for Classical Cepheid variables, sometimes

the world's most powerful telescope at the time. His observations of Cepheid variable stars in "spiral nebulae" enabled him to calculate the distances to

rate of pulsation of over a thousand cepheid variable stars in 25 galaxies. Theory suggests that the rate of cepheid pulsation in galaxies screened from

Pluto. Whipple's thesis was on the cepheid variables, titled A Spectrophotometric Study of the Cepheid Variables η Aquilae and δ Cephei. The measurements

mechanism for pulsating variables is believed to account for cepheid-like pulsations. The pulsational instability of Cepheid variables correlates with variations

to discover the relation between the luminosity and the period of Cepheid variables. Leavitt's discovery provided astronomers with the first standard

F-type spectra. The variables follow a period-luminosity relation in certain passbands like other standard candles such as Cepheids. and, together with