The difference between seat and system

Constellation is just the connection of several stars in a certain area in the sky, and there is no other meaning, while galaxy refers to a large-scale gathering area composed of a group of planets or stars in practical sense. For example, the solar system is a planetary system and the Milky Way is a star system. Every star has its own motion. In our opinion, the orbital differences of different stars are irregular, and they are everywhere, but their speed is very slow relative to ours, and they are far away from us in the order of several kilometers or more per second.

Characteristics of galaxies:

1. Galaxies vary greatly in size.

Elliptical galaxies range in diameter from 3,300 light years to 490,000 light years. The diameters of spiral galaxies range from 654.38+0.6 million light years to 654.38+0.6 million light years. Irregular galaxies are about 6,500 to 29,000 light-years in diameter.

2. The mass of galaxies is generally between 654.38+0 million and 654.38+0 trillion times the mass of the sun.

3. The stars in the galaxy are moving, the galaxy itself is rotating, and the whole galaxy is also moving in space.

Traditionally, astronomers believe that the rotation of galaxies, clockwise and counterclockwise ratio is the same. However, according to the observation results of a distributed participation project of galaxy classification, more galaxies rotate counterclockwise.