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> Polaris System - Illustration

Polaris System - Illustration

author: Nasa/ESA/Novapix

reference: a-eto01-01503

Image Size 300 DPI: 20 * 25 cm

This is a view from within the Polaris triple star system. The North Star, Polaris A is a bright supergiant variable star.Just above Polaris is a small companion, Polaris Ab, which is 2 billion miles from Polaris. Much farther away, near the top of the illustration, is the wide companion Polaris B. Polaris B is located approximately 240 billion miles from Polaris A. The two companion stars are the same temperature as Polaris A, but are dwarf stars. The wide companion star is visible in small telescopes. It was first noticed by William Herschel in 1780. The close companion, Polaris Ab was known to exist from measurements of a wobble in Polaris, caused by the gravitational tug of its companion, but has only been seen directly now using Hubble.

Keywords for this photo:

2006 - ASTRONOMY - CEPHEID - F STAR - ILLUSTRATION - POLARIS - POLARIS Ab - POLARIS B - POLE STAR - STAR - TRIPLE STAR - VARIABLE STAR -