What is Andromeda?

What is Andromeda? The twelve constellations are very mysterious. Some people think that the superstitions of constellations are too strong to be believed. If you really understand this constellation, you will find that it is actually cold outside and hot inside. What is Andromeda?

What is Andromeda 1 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. Andromeda is characterized by two curves starting from Alpha, and you can easily find it from the connection between Cassiopeia and Polaris.

Andromeda is the daughter of Cassiopeia, the fairy queen in Greek mythology. The fairy's head is Cedius, a corner of the Pegasus quadrangle. 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.

What is Andromeda 2 Andromeda galaxy, also known as Andromeda galaxy? It is a spiral galaxy with a huge disk structure, located in the direction of Andromeda, with a diameter of 220,000 light years and a distance of 2.54 million light years from the Earth. It is the closest giant galaxy to the Milky Way.

Andromeda galaxy is numbered M3 1 in messier catalog and NGC 224 in the new nebula cluster list. It looks like a spindle-shaped oval spot in the northeast sky and is the farthest celestial body visible to the naked eye.

Andromeda and the Milky Way are both in this galaxy group, with twice the mass of the Milky Way and at least 1.5 times the diameter.

Andromeda galaxy is the largest galaxy in this galaxy group, and it is moving towards the Milky Way at a speed of 300 kilometers per second. After 3-4 billion years, it may hit the Milky Way and eventually synthesize an elliptical galaxy.

Galactic structure

According to the shape seen in visible light, Andromeda galaxy is classified as spiral galaxy SA(s)b under the extension and expansion classification system of de Vaucouleurs-Sandage. However, in the data of the 2MASS survey, the core ball of M3 1 is box-shaped, which implies that M3 1 is actually a rod-spinning galaxy, and we observe this galaxy almost in the direction of the long axis. Andromeda galaxy is also a LINRER galaxy (low free nuclear radiation region), and it is a very common active galactic nucleus in classification.

In 2005, astronomers used the Keck telescope to observe tiny stars that were ejected and extended outward. They were actually part of the main astrolabe. This means that the spiral disk of Andromeda galaxy is three times larger than previously estimated. This evidence shows that the Andromeda galaxy disk is a huge and extended astrolabe with a diameter of more than 220,000 light years. Early estimates of the diameter ranged from 70,000 to 65,438+020,000 light years.

The inclination of the galaxy relative to the earth is estimated to be 77 (90 when viewed directly from the side), and the cross section of the galaxy is shaped like the letter S, not a plane. One possible reason for this shape distortion is the interaction between M3 1 and satellite galaxies gravity. Spectroscopic observations provide detailed measurements of the rotational speed of galaxies at different radii from the core. In the area near the core, the rotational speed reaches a peak of 225 km/s (140 mph); It begins to descend at the radius of 1 300 light years, and reaches a minimum of 50km/s (3 1 mile/hour) at 7000 light years. Then, the speed rises steadily, reaching a peak of 250 km/s (155 mph) at a radius of 33,000 light years. Beyond this distance, the speed slowly drops to 200 km/s (124 mph) at 80,000 light years. These velocity measurements show that the mass concentrated in the core is about 6× 109M⊙, and the total mass linearly increases to a radius of 45,000 light years, and then gradually slows down with the increase of the radius.

The spiral arm of Andromeda galaxy extends a series of ionized hydrogen regions, which Budd described as "a string of pearls". They look closely intertwined, but they are far apart in our galaxy. The corrected galaxy map clearly shows that there are spiral arms rotating clockwise around spiral galaxies. About 1, 600 light years away from the core, there are two continuous spiral arms dragging outward, and the nearest distance between them is about 1, 3000 light years away. The spiral pattern may be due to the interaction with M32. These substitutions can be observed through the neutral hydrogen clouds of stars.

1998, the image from the Infrared Space Observatory of the European Space Agency shows that the overall image of Andromeda galaxy may turn into a ring galaxy. The gas and dust in the Andromeda galaxy form several overlapping rings, the most prominent of which is located within a radius of 32,000 light years from the core. This ring is made of cold dust, so it is invisible in visible light images.

More detailed observation shows that there is a smaller dust ring inside, which is believed to be caused by the interaction with M32 two million years ago. Simulation shows that this smaller galaxy passes through the disk of Andromeda galaxy along the polar axis. The collision stripped more than half the mass from the smaller M32 and created a ring structure in the Andromeda galaxy.

The study of M3 1 extended halo shows that the stars in the universe are also poor in metals, and become poorer with the increase of distance. These evidences show that the two galaxies follow similar evolutionary routes. In the past 65.438+0.2 billion years, they may have swallowed 654.38+0-200 low-mass galaxies. The stars in the extended halo of M3 1 may be close to one third of the distance between the two galaxies.

What is Andromeda 3 Andromeda is Andromeda.

Andromeda is one of the 88 constellations in the whole day, located below Ursa Major and near Pegasus. Andromeda is famous for the Andromeda galaxy M3 1.

The alpha star that constitutes this quadrilateral is the brightest star in Andromeda, which extends northeast from the diagonal of Alpha Pegasus to the alpha Andromeda in the quadrilateral, and the three bright stars of Andromeda are almost all on this extension line. Further on, you will meet the great spirit of Perseus. Daling V, Perseus α and Andromeda γ form a right triangle.

Extended data:

Andromeda symbolizes Andromeda, the "goddess bound by chains" in Greek mythology, the wife of Poerxiusi, the daughter of the legendary Ethiopian king Capes and queen Casiopeia. In this Greek and Roman myth, Casio Paya shows off that her daughter is more beautiful than the Nereid sea fairy, and the sea fairy complains to Poseidon, hoping that he can punish Casio Paya for her rude remarks. Poseidon therefore let the sea monster Ceto invade Ethiopia.