Skywatch

  • February 16, 2006

    Episode 23: Polaris' Third Star

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    Shownotes

    The North Star, that friendly, constant guide to sailors and travelers, is actually the North Stars. Scientists have known for some time that Polaris, though it looks like a single bright light from our perspective, is really a star system. The latest images from the Hubble Space Telescope show for the first time a third star, long hidden in the glare of the other two stars in the system. Polaris is a supergiant star more than 2,000 times brighter than Sun. Its distance from Earth makes Polaris only a medium-bright star in our sky - not the brightest by a long shot. Fifty other stars are brighter. The newly photographed companion star is a little more massive than Sun, as well as a little brighter, and a little hotter.