What classification describes the primary star component, Polaris A (or Polaris Aa), in terms of stellar evolution and brightness variation?

Answer

A yellow supergiant and Classical Cepheid variable

Polaris A, the brightest member of the triple star system, is characterized as an evolved yellow supergiant. Furthermore, it is classified specifically as a Classical Cepheid variable star. This classification is highly significant in astrophysics because Cepheid variables exhibit a periodic change in their actual brightness, or luminosity, which is directly correlated with their pulsation period. This relationship allows astronomers to use them as 'standard candles' to accurately measure vast cosmic distances. Polaris Aa pulsates, causing its visible magnitude to fluctuate between 1.86 and 2.13 over a period of roughly four days, although its variation behavior has shown peculiar instabilities in recent decades.

What classification describes the primary star component, Polaris A (or Polaris Aa), in terms of stellar evolution and brightness variation?

Related Questions

What celestial point is Polaris almost exactly above when traced from the geographic North Pole?For an observer in the Northern Hemisphere, what geographical measurement is directly related to the altitude of Polaris above the northern horizon?What is the approximate ranking of Polaris's brightness compared to all other stars visible at night?Which two stars forming the outer edge of the Big Dipper's bowl are used as 'pointer stars' to find Polaris?Which constellation is Polaris the bright tip of the handle for, although it is generally fainter than the Big Dipper?What astronomical phenomenon, caused by the slow wobble of Earth's axis, dictates that Polaris's title as North Star is temporary?What classification describes the primary star component, Polaris A (or Polaris Aa), in terms of stellar evolution and brightness variation?What is the orbital period for the closest companion star to Polaris A, identified as Polaris Ab?In Hindu tradition, what name personifies Polaris, meaning 'immovable' or 'fixed'?According to the latest Gaia mission data referenced, what is the estimated distance of the Polaris triple star system from Earth in light-years?
astronomystarsnavigationNorth Starpolaris