What does Andromeda mean?

Andromeda is one of the 88 constellations in the whole day, located below Ursa Major and near Pegasus. Andromeda is Andromeda in Greek mythology, and the head of the fairy is Sedius, which is a corner of the trapezium of Pegasus. Andromeda has a main galaxy, M3 1 (Andromeda galaxy), which is one of the largest members of the galaxy cluster.

The starry sky in autumn is not as bright as that in spring and summer. A group of royal constellations is the biggest feature of the autumn sky. The protagonists of these royal constellations are the kings, queens and princesses of ancient Ethiopia, as well as the warrior who rescued the princess from the monsters in the sea, namely Yingxian. Among many royal constellations such as Cepheus, Cassiopeia, Andromeda and Perseus, Andromeda is the most attractive constellation because of its M3 1. The Andromeda Nebula is located in the center of Andromeda, and it can be seen in a vast area north of 48 south latitude.

In order to successfully find the Andromeda nebula among many stars, we need to be familiar with the autumn starry sky first. In autumn night, the Milky Way has turned to the northeast, and Cassiopeia can be seen swimming in the Milky Way. It has five bright stars, arranged in the shape of the English letter "W", which is easy to identify. To the west of Cassiopeia is Cepheus and to the east is Perseus. Not far from the south of the Milky Way, there are four bright stars arranged in an obvious quadrilateral, which is the famous autumn quadrilateral. All three stars in the quadrilateral belong to Pegasus, and only the star in the northeast corner is Andromeda A star. The visual magnitude of Andromeda A is level 2, white. Andromeda is north of 12, and there is a third-class binary star about 5 east. It is Andromeda gamma star, and its Chinese name is General Tian. We should pay special attention to this "heavenly general". The Andromeda nebula M3 1 is very close to it, just to the west 1.

The Andromeda Nebula has a total magnitude of 4 and an average brightness of 6 per unit area. On a clear moonless night, it is faintly visible to the naked eye, like a small white cloud. Its soft silvery white oval shape can be seen through a small astronomical telescope. Andromeda nebula is a typical spiral galaxy, but because it faces us sideways, it is not easy to see its spiral arms. Through a larger telescope, we can see some of its structures, for example, its core is particularly bright, and the brighter it gets toward the center, we can also see some spiral arms, black dust lines, globular clusters and star clouds. In addition, we can also see its two dwarf companion stars, one is a small, round and dense elliptical galaxy M32 in the south of M3 1, and the other is an elliptical galaxy M 1 10, which is slightly darker but larger and longer than M32 and located in the northwest of M3 1. There are also many dim stars in the Milky Way that fill this sky area, adding fascinating colors to the Andromeda Nebula.