Physics & Chemistry


October 31, 2011, 10:51 pm

Polaris (currently the pole star) is  located in the constellation Ursa Minor, also known as the Little Dipper, and actually comprises a triple-star system, made up of Polar Aa, Polaris Ab and Polaris B. Polaris Aa is a giant star (spectral class F7), almost 44 times the diameter of the Sun, six times more massive and over 2204 times more luminous. The large distance between our solar system and the Polaris system (430 light years) makes this very bright star appear comparatively faint in our heavens.

This article is written at a definitional level only. Authors wishing to improve this entry are inivited to expand the present treatment, which additions will be peer reviewed prior to publication of any expansion.

Polaris B (spectral class F3) is a main sequence star about 50 percent more massive than the Sun and much fainter than Polaris Aa. Polaris Ab is a minute stellar object detected by the Hubble Space telescope that orbits in proximity to Polaris Aa.


  • Nancy Remage Evans; Gail Schaefer; Bond; Edmund Nelan; Giuseppe Bono; Margarita Karovska; Scott Wolk; Dimitar Sasselov et al. (2006). "Polaris: Mass and Multiplicity". Proceedings of the International Astronomical Union 2.
  • Cayrel de Strobel, G.; Soubiran, C.; Ralite, N. (2001). " Catalogue of [Fe/H] determinations for FGK stars: 2001 edition ". Astronomy & Astrophysics 373: 159–163


(2011). Polaris. Retrieved from


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