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Astronomy Picture of the Day -
NASA ^ | 14 Jan, 2025 | Image Credit & Copyright: Davide Coverta

Posted on 01/14/2025 1:15:41 PM PST by MtnClimber

Explanation: Why is Polaris called the North Star? 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 bright 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 five-degree wide featured image, a digital composite of hundreds of exposures that brings out faint gas and dust of the Integrated Flux Nebula (IFN) all over the frame. The surface of Cepheid Polaris slowly pulsates, causing the famous star to change its brightness by a few percent over the course of a few days.


TOPICS: Astronomy; Astronomy Picture of the Day; Science
KEYWORDS: apod; nasa
To be added or removed from the Astronomy Picture of the Day ping list please send me a request via "Private Reply" (Mail).

For more detail go to the link and click on the image for a high definition image. You can then move the magnifying glass cursor then click to zoom in and click again to zoom out. When zoomed in you can scan by moving the side bars on the bottom and right side of the image.

1 posted on 01/14/2025 1:15:41 PM PST by MtnClimber
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To: MtnClimber

2 posted on 01/14/2025 1:16:01 PM PST by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: 21stCenturion; 21twelve; 4everontheRight; A Navy Vet; A_perfect_lady; abb; AFB-XYZ; AFPhys; ...
Pinging the APOD list

🪐 🌟 🌌 🍔

3 posted on 01/14/2025 1:17:05 PM PST by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: MtnClimber
Title should be:

North Star: Polaris and Surrounding Dust

4 posted on 01/14/2025 1:18:17 PM PST by MtnClimber (For photos of scenery, wildlife and climbing, click on my screen name for my FR home page.)
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To: MtnClimber

Cool!


5 posted on 01/14/2025 1:22:41 PM PST by mitch5501 ("make your calling and election sure:for if ye do these things ye shall never fall")
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