Where do the Big Dipper and Polaris appear in the clear night sky?

The Big Dipper appears in different directions in the sky at different seasons and different times at night, so the ancients decided the seasons according to the direction pointed by bucket handle at the beginning of fainting: bucket handle points to the east, and the world is spring; Guide to barrel handle, it's summer in the world; Bucket handle refers to the west, and the world is autumn; The barrel handle refers to the north, and it is winter all over the world.

The Big Dipper is moving, the North Star is stationary, and the Big Dipper constellation revolves around the North Star.

Beidou consists of Shu Tian, Tian Xuan, Tianji, Tianquan, Yuheng, Kaiyang and Yaoguang. The ancient Han people associated these seven stars together and imagined them as barrels of ancient wine.

The Big Dipper is named α, β, γ, δ, ε, ζ and η respectively from the upper end of the bucket to the end of bucket handle. Astronomers of the ancient Han nationality in China called them Shu Tian, Tian Xuan, Tianji, Tianquan, Yuheng, Kaiyang and Yaoguang respectively. A straight line from Tian Xuan runs through Shu Tian, which is about five times as long as it. You can see a star as bright as the Big Dipper, which is the North Star.

Now Polaris is a bright star named Dog, and its western name is Dog Eye. This star is located at the tip of the bear's tail in Ursa minor. In English, Cynosure also means center of attraction, which means that the stars revolve around the hook. It should be noted that today's Polaris Gouchenyi has nothing to do with the purple star and purple wall in ancient China. I hereby make a special correction.

Polaris is a bright star in the northern part of the sky, close to the north celestial pole and almost opposite the earth axis. Seen from the northern hemisphere of the earth, its position is almost unchanged, so it can be used to identify the direction. However, due to precession, Polaris is not a star whose position will never change, and it will be Vega by the year 14000. Every 25,800 years, Polaris will cycle. For example, during Magellan's voyage, Gouchen-1 was about 8 degrees from the north celestial pole, but today, Gouchen-1 is closer to the north celestial pole with an angle difference of only 40'. According to the calculation of the earth's axis swing and stellar gravity, by 2 100, Gou Chenyi will reach the nearest position directly above the North Pole, only 28' away from the North Celestial Pole, and then, Gou Chenyi will gradually.

Polaris is the brightest star in Ursa minor at present, that is, Alpha in Ursa minor. It is a yellow giant with spectral type F, about 434 light-years away from the Earth, and its mass is about four times that of the sun. It is the brightest star closest to the earth and is at the tip of the bear's tail in the constellation diagram. Gou Chenyi is also a star of underworld nature.

Connect a straight line between Tian Xuan and Shu Tian at the front end of the Big Dipper, and then extend the distance five times to Shu Tian. You will meet a bright second-class star, which is Gou Chenyi. This is the easiest way to find Gou Chenyi.