Besides the Milky Way and the solar system, what other galaxies are there?

Outside the Milky Way, there are many celestial systems similar to the Milky Way, with the number exceeding 654.38+0 billion, which are collectively called "extragalactic galaxies". Among them, the most famous extragalactic galaxies are Andromeda, Large Magellanic Galaxy, Small Magellanic Galaxy, Canis Extragalactic Galaxy and Triangle Galaxy. These galaxies are also very close to our galaxy. ?

Andromeda galaxy 1(m 3 1)

Andromeda galaxy is a typical spiral galaxy, larger than the Milky Way, with a diameter of 65.438+0.6 billion light years, while the diameter of our Milky Way galaxy is 65.438+0.6 billion light years. There are at least 200 million stars in the Andromeda galaxy. Andromeda galaxy is 2 million light years away from our earth.

2. large magellanic cloud.

It is 654.38+0.6 million light years away, located at the junction of the Swordfish and Yan Luowang constellations. So far, it is only about one-fifth of the Milky Way, but it contains at least about 20 billion stars.

3. Small Magellanic Cloud

About 2 10000 light years away, it is located in the constellation Rhododendron, which is usually observed only in the low latitudes of the southern hemisphere and the northern hemisphere, but this galaxy is one of the most distant celestial bodies visible to the naked eye.

4. Wide-brimmed hat galaxy

The straw hat galaxy is also known as the wide-brimmed hat galaxy and the Mexican straw hat galaxy. It is a Sa-Sb spiral galaxy, located in Virgo, 29.3 million light years away from the Earth, with a luminosity of 8.7. Messier number M 104, NGC 4594.

5. Black-eyed galaxy (M64, NGC4826)

Black-eyed galaxies, also known as Sleeping Beauty Galaxies and magic eye Galaxies, are named after a spectacular dark dust belt, which spans in front of the bright galaxy core and is located in the backward constellation, about 6.5438+0.7 million light years away from us.

6. Binary system (2MASX J00482 185-2507365 occultation pair)

Twin galaxies consist of two overlapping spiral galaxies, which are located near Jade galaxy (NGC 253). Their light illuminates the surrounding dust belt, just like a lamp, illuminating an area with a radius six times that of its galaxy. With its help, astronomers observed some galaxies with insufficient light.

Extended data:

1, the extragalactic galaxy refers to a large number of stars outside the Milky Way, but it is also called "extragalactic nebula" because it is far away and appears in the form of fuzzy light spots.

People have observed about10 billion galaxies similar to the Milky Way. According to their shapes and structures, they can be divided into spiral galaxies, rod-spiral galaxies, elliptical galaxies and irregular galaxies. It is estimated that the total number of extragalactic galaxies exceeds 1000 billion. The most common classification of extragalactic galaxies was proposed by Hubble in 1926. The discovery of extragalactic galaxies extends human knowledge beyond the distant Milky Way for the first time, which is an important milestone in the process of human exploration of the universe.

No one knows how many galaxies there are in the universe. Hubble classified them into three types according to their shapes: elliptical galaxies, spiral galaxies and irregular galaxies. Elliptic galaxies can be divided into seven types, which are expressed by E0-E7 according to the oblateness of galaxy ellipses from small to large, and the maximum value of 7 is arbitrary.

Another lens galaxy, denoted by S0, represents a transitional galaxy between an elliptical galaxy and a spiral galaxy. The familiar Andromeda galaxy cluster (including NGC4552, NGC4486, NGC4479, etc. ), Abel 22 18 cluster, and NGC205 elliptical galaxy with small Magellanic cloud, belonging to E6 type, located in Andromeda. NGC3 1 15, located in sextant, belongs to E7 elliptical galaxy, and some people classify it as S0 type. NGC3623 is located in Leo and belongs to Sa spiral galaxy.

This classification is limited to the shape of galaxies seen from the earth, because the angle of elliptical galaxies in space is difficult to determine. Spiral galaxies are divided into two groups. One group is a rod-like spiral galaxy with a rod-like structure in the center, which is represented by SB. The other is a spiral galaxy without a rod structure, which is denoted by S. These two types of galaxies are subdivided into three subtypes, and the subscripts A, B and C denote the size of the galactic nucleus and the tightness of the spiral arm respectively. Irregular galaxies have no certain shape and contain more dust and gas, which is expressed by Irr.

Sb NGC3627 spiral galaxy is located in Leo. ? The spiral galaxy NGC5 194 in Canine constellation belongs to Sc type. On the left is a dwarf galaxy. NGC335 1, located in Leo, belongs to the SBb-type rod spiral galaxy. SBc rod spiral galaxy NGC3992 is located in Leo. The satellite system of the Milky Way is the Large Magellanic Cloud, which is an irregular galaxy. NGC3034 is an irregular galaxy located in Ursa Major.

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