NASA: Astronomy Picture of the Day(2023-04-11)

lalaloo 입니다.

This photo is the Astronomy Picture of the Day provided by NASA.

나사에서 매일 업데이트하는 오늘의 우주 모습입니다.

 

Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

이 사진의 제목은 <North Star: Polaris and Surrounding Dust> 입니다.

해당 작품의 소유권은 Javier Zayaz 에게 있습니다.

 

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 eight-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 as well as the globular star cluster NGC 188 on the far left. 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. Explore Your Universe: Random APOD Generator