North Star Polaris Portal

Polaris B can be seen even with a modest telescope. William Herschel discovered the star in August 1779 using a reflecting telescope of his own, one of the best telescopes of the time. By examining the spectrum of Polaris A, it was also discovered in 1929 that it was a very close binary, with the secondary being a dwarf (variously α UMi P, α UMi an or α UMi Ab), which had been theorized in earlier observations (Moore, J. H. and Kholodovsky, E. A. ). In January 2006, NASA released images, from the Hubble telescope, that showed the three members of the Polaris ternary system. Ab, the nearby dwarf star, is in an orbit of 18. 5 AU (2. 8 billion km) from Polaris Aa, about the distance between the Sun and Uranus, which explains why its light is swamped by its close and much brighter companion.

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