What is the brightest star?

The brightest star closest to the north celestial pole is Polaris. Now the recognized Polaris is Alpha Ursa minor, which was called "Gouchenyi" and "Beichen" in ancient China. It is an F-type high luminosity star with a late spectrum, with an apparent magnitude of 2.02 and a distance of 430 light years, and its mass is about four times that of the sun. It is the Cepheid variable closest to the earth and is at the tip of the bear's tail in the constellation diagram.

Polaris is a star with stable brightness and position that can be seen in the night sky. After long-term observation, astronomers found that almost all the stars rise in the east and set in the west, and only Polaris seems to be stationary. The earth always revolves around an imaginary axis of rotation from west to east, so that day and night alternate and the stars rise and set in the west. If the imaginary axis of rotation extends to the west indefinitely, the extension line on one side will pass near the Polaris, which is called the North Celestial Pole. The direction it refers to is due north and the opposite is due south. Polaris is closest to the north celestial pole, and she means due north. Seen from the earth, its position has hardly changed. For thousands of years, people on the earth often rely on its light to find their way at night.

"First recognize the stars from Beidou, and then from north to west." Beginners can look for other constellations in turn from the Big Dipper. Looking for Polaris, we must first find Ursa major, because it always keeps a certain position relationship with Polaris and keeps rotating. After the Big Dipper was found, it extended to the mouth of the spoon along the connecting line of the two stars A and β on the spoon side, which is about five times the distance between the two stars A and β, and there is a brighter star, the Polaris.