points: These stars also vary in brightness, but not on the rapid timescale of pulsars.
points: These stars also vary in brightness, but not on the rapid timescale of pulsars. Astronomers hunt them as rare prizes because a relation between their period and true luminosity makes them ideal as standard candles. Edwin  Hubble used them to establish that the Andromeda nebula is, in fact, a different galaxy.
points: These stars also vary in brightness, but not on the rapid timescale of pulsars.
{Cepheid variables}