Our Friend In The North

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Behold: an image of Polaris – the North Star – digitally manipulated to suppress surrounding dim stars but accentuate the faint gas and dust of the Integrated Flux Nebula (IFN). Fair enough. But why is it called the North Star? To wit:

First, Polaris is the nearest bright star toward the north spin axis of the Earth. Therefore, as the Earth turns, stars appear to revolve around Polaris, but Polaris itself always stays in the same northerly direction — making it the North Star. Since no bright star is near the south spin axis of the Earth, there is currently no South Star. Thousands of years ago, Earth’s spin axis pointed in a slightly different direction so that Vega was the North Star. Although Polaris is not the brightest star on the sky, it is easily located because it is nearly aligned with two stars in the cup of the Big Dipper. Polaris is near the center of the eight-degree wide featured image (…/) The surface of Cepheid Polaris slowly pulsates, causing the star to change its brightness by a few percent over the course of a few days.

(Image: Bray Falls)

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2 thoughts on “Our Friend In The North

  1. TheFerg

    As I and a few others have commented previuously – we love these posts.
    I’ll do my own research, (dangerous words these days!), on the distance between Polaris, the nebula and ourselves.

    Please, for the love of Jesus, Mary, Joseph and the wee donkey – keep these posts coming!!

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