What is the Big Dipper? Stellar system? Galaxy?

The Big Dipper is Shu Tian, Tian Xuan, Celestial Pole, Tian Quan, Yuheng, Kaiyang and Yaoguang in the constellation Ursa Major. People in ancient China associated these seven stars and imagined them as barrels of wine in ancient times. Difference: The seven stars in Ursa Major are called Little Beidou; The emperor star is in Ursa minor, and Beidou is in Ursa major. The so-called bucket is an emperor car.

A star system is defined as a collection of countless celestial bodies (and stars) that can emit light and heat. Star system, or galaxy, is an "island" of giant stars in the universe, and it is also one of the largest and most beautiful celestial systems in the universe. So far, people have observed about 10 billion galaxies in the universe. The Milky Way is just an ordinary galaxy.

Extended data:

The Big Dipper is a part of Ursa major. Graphically, the Big Dipper is located at the tail of Ursa Major. Six of these seven stars are secondary stars, and 1 is tertiary. Through the connection of the two stars in the mouth of the bucket, it extends about 5 times in the direction of the mouth of the bucket and finds the Polaris.

"Star Recognition Song" has: "Star recognition begins with Beidou, and then begins from north to west." Beginners can look for other constellations in turn from the Big Dipper. The seven stars of Ursa Major are arranged in the shape of a spoon. The ancients attached great importance to Beidou because it can be used to identify the direction and set the season.

The discovery of star systems can be traced back to more than 200 years ago. In the catalog compiled by French astronomer messier at that time, the nebula numbered M3 1 occupies an important position in the history of astronomy. In the early winter night, people familiar with the starry sky can find it with the naked eye in Andromeda-a fuzzy spot, commonly known as the Andromeda Nebula.

Since 1885, many new stars have been found in Andromeda Nebula, and it is concluded that Andromeda Nebula is not the usual dust gas cloud that passively reflects light, but must be a system composed of many stars, and the number of stars must be extremely large, so there may be so many new stars in it.

References:

Baidu Encyclopedia-Big Dipper

References:

Baidu Encyclopedia-Star System