Description
Andromeda is a constellation of the northern hemisphere that has a characteristic pattern called an asterism. These are the three brightest stars located in a line stretching from northeast to southwest.
Alamak (γ Andromedae) is a triple system consisting of a yellow main star with a magnitude of 2 m and its satellites - two physically connected bluish stars. The star Alferaz (α Andromeda, 2.1 m) has two more names: Alpharet and the full Arabic name “Sirrah al-Faras”, which means “navel of the horse”. Both belong to the so-called navigation stars, by which sailors determine their position at sea.
Among other, less noticeable stars, very interesting ones can be distinguished: υ Andromeda, around which a planetary system similar to the Solar one was discovered, and ο Andromeda - a variable star of an unknown type, changing the amplitude of its brightness from 3.5 to 4.0 magnitude. The spectrum of this star shows that it consists of two stars orbiting a common center of mass. The rotation period is one and a half days.
The most important object in the constellation is probably the most famous nebula - the Andromeda Nebula; This is the M31 galaxy. It can be seen on a moonless night even with the naked eye as a small foggy spot.
M31 is the closest spiral galaxy to us, which is approximately 2.2 million light years away from Earth. Inside the nebula there are about 170 globular star clusters, and outside it is surrounded by four much smaller star systems, the so-called dwarf galaxies. With the discovery of M31, systematic observations of galaxies began, in which the Hubble Space Telescope plays a special, significant role.
The most interesting objects
Andromeda nebula or galaxy M31. Visible to the naked eye as a nebulous spot in the constellation Andromeda
M31 - NGC 224 - Andromeda Nebula- a spiral galaxy, the brightest in the earth's sky (excluding the Magellanic Clouds). This is the largest galaxy closest to the Milky Way, which, together with its satellites, is part of the Local Group of galaxies M31, visible to the naked eye as a large nebulous cloud with a brightness of 3.4 m. In 1923, Edwin Hubble discovered the first Cepheid in the Andromeda nebula and, by determining its distance, established the true nature of M31 and the real intergalactic scale. Today, the distance to the Andromeda nebula is estimated at 2 million 900 thousand light years. years. This is the most studied of the known galaxies, because it is much easier to learn the structure of our Galaxy by studying its similarity from the outside. Research in recent years has shown that the Andromeda nebula is in interaction with its satellite M32, which, in turn, causes disturbances in its spiral structure. Modern astronomical instruments make it possible to study individual objects located in the Andromeda nebula. So, it turned out that there are more than 300 globular star clusters in this galaxy. Among them, a real giant was discovered - the G1 cluster, which is the brightest in the Local Group of galaxies. The angular dimensions of M31 are 178×63", which corresponds to linear dimensions of 200 thousand light years. The mass of this galaxy is approximately equal to 300-400 billion solar masses. According to modern estimates, this is less than the mass of our Galaxy. The Milky Way is smaller in size Andromeda nebula, but denser. Studies carried out by the Hubble Space Telescope have shown that M31 has a double core. Recently, the space telescope has discovered many double cores in galaxies. This may be due to the constant process of galaxy collisions. The Andromeda nebula could have absorbed a dwarf galaxy, the core which is located next to its own. M31 is moving towards our Galaxy, and in about 4-5 billion years the neighbors should collide. The Andromeda nebula has about 10 satellite galaxies. The two brightest of them are M110 (NGC 205) and M32 - are easily observed in small amateur telescopes.
γ Andromeda- a double star consisting of two components with a magnitude of 2.2 m and 5.0 m. 56 Andromeda is a double star consisting of two 6th star components. quantities.
NGC 752- an open star cluster occupying an area in the sky equal to two lunar disks (60"). It is best observed through a telescope with low magnification or binoculars. Contains about 60 stars. Brightness - 5.7 m. Distance from the Sun at a distance of 1300 light . years.
S Andromeda- a supernova belonging to the Andromeda nebula (M31). It was observed on August 20, 1885, but if we take into account that the light from M31 travels for about 3 million years, then this star flared up much earlier. The star's brightness reached 6th magnitude. quantities. By February 16, 1890, the star ceased to be observed.
NGC 7662- a planetary nebula, clearly visible in a small amateur telescope. When using the powerful tool, a beautiful blue-green disc is visible. Brightness - 9 m, angular diameter - 5".
M32 - NGC 221- elliptical galaxy type E2, satellite of the Andromeda nebula. It is a member of the Local Group of galaxies. It has a brightness of 8.1 m and is easily observed in small amateur telescopes. It is a dwarf galaxy with a mass of 3 billion solar masses. The angular dimensions in the sky are 8×6", linear - 8 thousand light years. M32 consists mainly of old stars. In galaxies of this type, only low-mass stars are observed, because they are longer-lived. All high-mass stars have already evolved and become into white dwarfs, neutron stars or black holes. Studies of M32 show that in this galaxy there are no interstellar gas and dust clouds, planetary nebulae, open star clusters. There is no star formation. The youngest stars are about 2-3 billion years old. Study of the core M32 showed that its mass is almost equal to the core of the Andromeda nebula and is equal to approximately 100 million solar masses. It is possible that this galaxy was previously more massive and lost its stars and globular star clusters when interacting with other galaxies, in particular with M31. Maybe Perhaps the stars of the spiral arms and diffuse matter were captured by the Andromeda nebula and are now part of its halo.On August 31, 1998, a new star flared up in M32. Its brilliance reached 16.5 m.
M110 - NGC 205- an elliptical galaxy of the E6p class, a satellite of the Andromeda nebula. This galaxy is a member of the Local Group of galaxies M110. It has a somewhat unusual structure and contains clouds of dust unusual for elliptical galaxies. It is called a dwarf spherical galaxy. The mass of M110 is small - about 3.6-15 billion solar masses. But despite this, a system of eight globular star clusters is observed around this dwarf galaxy. Brightness - 8.5 m, angular dimensions - 17"x10".
NGC 891- the second brightest galaxy in the constellation Andromeda. It is located at a distance of 3.4° from the star Al Maak (γ Andromeda). Brightness - 10 m, angular dimensions - 14"x2".
NGC 7640- SBb-class barred spiral galaxy. Brightness - 10.9 m, angular dimensions - 10.7"x2.5".
IC 239- barred spiral galaxy, class SBc. Brightness - 11.22 m, angular dimensions - 4.6"x4.3".
History of the study
The constellation Andromeda has been known since the Middle Ages and is included in the star atlas of Claudius Ptolemy “Almagest”.
The Andromeda nebula was discovered by the Arab astronomer Al-Sufi. He described it in his Book of the Fixed Stars (964 AD) as a "little cloud" which he observed for 60 years. In Europe, seven hundred years later, the nebula was described by Galileo's contemporary and colleague in the first telescopic observations, Simon Marius. Another European, Giovanni Batista Odierna (1597-1660), independently of Al-Sufi and Marius, discovered the site in late 1653.
Observation
The constellation Andromeda is clearly visible throughout Russia. It is located high in the night sky, making it accessible to study throughout the night. The best time for observations is November, but you can start from September.
Finding the constellation is not difficult. On an autumn evening on the southern side of the sky you need to find the Great Square of the constellation Pegasus. In its northeastern corner (“upper left”) is the star Alferaz (α-Andromeda), from which the constellation Andromeda stretches to the northeast.
To the left is the “compass” of Perseus, and above is the constellation Cassiopeia, with a characteristic pattern in the form of a large letter “W”.
There are thousands of stars in the night sky. Man has always shown interest in the mysterious picture of the Universe, finding in it new incomprehensible and mysterious objects and constellations. Time passed, but the eternal desire for the mystery of the Universe did not weaken, but, on the contrary, only intensified. Today, with the help of spacecraft, man has managed to look into the outskirts of the solar system. Descent modules landed on many planets. Powerful space telescopes have peered beyond the edge of the abyss.
Constellations are a group of stars grouped in a certain way. People noticed this in ancient times and began to give names to the constellations. Many modern names of constellations came to us from Ancient Greece and Ancient Rome. They reflect the content of mythical stories about gods, heroes, battles and journeys. These stories largely gave rise to European culture and became the subjects of many great works of art.
Andromeda is a constellation of the northern hemisphere, consisting of three bright stars located in a line. The Alamak star is a triple system consisting of a yellow main star with a magnitude of 2m and two of its satellites - bluish stars. Star Alpherats (another name is Alpharet, in Arabic “Sirrah ap-Faras”, translated as “navel of a horse”). Both stars are navigation stars by which sailors navigate the sea. The third star is Mirakh, located between them.
The main object in the constellation is the Andromeda Nebula - galaxy M31. It can be observed with the naked eye on a moonless night as a small foggy spot. M31 is the closest spiral galaxy to Earth, located at a distance of 2.2 million light years. There are about 170 globular star clusters inside, and outside the nebula are four small star systems called dwarf galaxies.
In Greek myths, Andromeda is the daughter of the Ethiopian king Kepheus (Cepheus) and Queen Cassiopeia. Once Cassiopeia boasted of her beauty to the nymphs, which angered them. They complained to the god of the seas, Poseidon, who decided to punish the proud queen. He sent a flood and a sea monster - Whale - to the kingdom of Kepheus. The whale came out of the water and devoured people and animals. Kepheus asked the priests of the god Zeus for help, but they predicted that it was possible to get rid of Keith if Andromeda was sacrificed to him. The people who suffered from Keith demanded that the king fulfill this prediction, and Andromeda was chained to a rock on the seashore. Flying over Ethiopia, on his winged sandals, Perseus - the son of Zeus and Danae - noticed Andromeda and decided to free her. At this time, a whale emerged from the depths of the sea and headed towards Andromeda. Rising into the air, Perseus struck the monster with his sword. Andromeda became the wife of Perseus and lived happily ever after with him, giving birth to Gorgophon, Persus, Alcaeus, Electryon, Sthenelus, Mestor and Hylaeus. After death, the gods turned Andromeda into a beautiful constellation.
The constellation can be seen at latitudes from -40° to +90°. The best time to observe is in November. Andromeda is clearly visible throughout Russia. In autumn, Andromeda is visible high above the horizon throughout the night. The constellation can be easily found in the sky using Pegasus, since the upper left star of its "square" actually refers to Andromeda. This is the star Alpheraz (Andromeda).
In winter, Andromeda is located on the northern side of the sky. During the night, it goes halfway beyond the horizon, and then rises into the sky again. Finding the constellation is easy. The chain of three stars on the left points to Perseus and Auriga, where the star Capella shines brightly.
In late summer, Andromeda moves east, where it can be easily found by the constellation Cassiopeia, which hovers directly above it with its instantly recognizable "W" asterism. Perseus, who looks like a dissolved compass, is on the left.
Andromeda is visible throughout the northern hemisphere. The constellation is easy to find if you find the Great Square of Pegasus in the southern sky on an autumn evening. In its northeastern corner is the star Alferats (α Andromeda), from which three chains of stars that make up Andromeda diverge to the northeast, towards Perseus.
Its three brightest stars of 2nd magnitude are Alferats, Mirakh and Alamak (α, β, and γ Andromedae), with Alamak being an amazing double star. The star Alferaz is also called Alpharet, Alferraz or Sirrah; her full Arabic name is "Sirrah al-Faras", which means "the navel of the horse" (sometimes she was included in the constellation Pegasus
Nereids - 50 beautiful and kind daughters of Nereus, a wise sea elder, were offended and complained to their patron, the God of the seas Poseidon (Roman Neptune).
The angry Poseidon, striking with his trident, sent a flood to the shores of Palestine and summoned a sea monster - Whale - from the depths of the sea.
To save the kingdom, King Cepheus turned to the oracle of Amun and learned that his subjects could be saved from the rage of the monster only if the royal daughter Andromeda was sacrificed to Keith. Cepheus could not resist the people, and Andromeda was chained to the rocks near the capital of Ethiopia.
When Keith was already approaching the girl, Perseus appeared at the scene of the tragedy.
Fortunately, Perseus, the mortal son of Zeus, flew past the helpless Andromeda, returning from a victorious battle with the Gorgon Medusa.
According to some versions, he moved thanks to winged sandals given to him by Athena, the Goddess of wisdom and courage. However, the indicated group of constellations is more consistent with the version that he flew on the winged horse Pegasus.
Struck by the virgin beauty of Andromeda, Perseus decided to fight the sea monster. In return, he asked Andromeda's father, Cepheus, for her hand in marriage. He naturally agreed.
Confusing the monster with his shadow, Perseus led the monster away from the shore far into the sea, and there dealt him a fatal blow. So, Perseus saved Andromeda.
Beyond the Greek legend remains the more mysterious symbolism of the constellation Andromeda, as evidenced by its very name, meaning “ruler over men.”
As the Roman poet Manilius (1st century AD) wrote, “he who slayed Medusa was struck by the beauty of Andromeda.” So, perhaps Andromeda is not as innocent and helpless as it seems at first glance, but rather similar to Aphrodite, personifying feminine attractiveness.
Confirmation of this can be found in Mesopotamian mythology, where this constellation was identified with Astarte, the Goddess of love and war. Temples on the Palestinian coast were dedicated to Astarte, the loving sea Goddess, where, according to myth, Andromeda was sacrificed.
The figure of the chained Andromeda can be fully visible from anywhere on earth north of 37° south latitude. The constellation is located to the west of the constellation Perseus, the savior of Andromeda, although the best reference is the bright W of Cassiopeia, located just to the north.
The head of Andromeda, as if falling, overlaps with the body of the winged horse Pegasus; The brightest star of the constellation, Alpher, is included in the northeastern corner of the Pegasus square. The constellation's midnight culmination occurs in the second week of October.
Alferats A is the brightest representative of an unusual class of “mercury-manganese stars.” In the atmospheres of such stars there is a significant excess of mercury, gallium, manganese and europium, and the proportion of other elements is extremely small. The anomaly is believed to be caused by the different effects of the star's gravity and radiation pressure on different chemical elements.
Alpherats belongs to the variable stars of the type α² Canes Venatici, the star’s brightness varies from +2.02m to +2.06m with a period of 23.19 hours.
Alferatz (also Alferat, Alpher, Sirra, Sirrah or Sira) - Alpha Andromedae (α And / α Andromedae), the brightest star in the constellation Andromeda, is located northeast of the constellation Pegasus. The names "Alferaz" and "Sirra" come from Arabic. سرةالفرس, şirrat al-faras, which translated means “the navel of a horse.”
Since antiquity, during the Middle Ages, until the 17th century and even later, this star was considered to belong simultaneously to two constellations - Andromeda and Pegasus.
Thus, Ptolemy describes it as belonging to the constellation Horse (Pegasus) “The star on the navel, common with the star on the head of Andromeda.”
For some time, Alferaz was also called the Pegasus delta (δ Peg). The final decision on whether this star belongs to the constellation Andromeda was made by the IAU in 1928. Currently, the constellation Pegasus does not have a star δ.
Mirakh(Mirac, Beta Andromedae, β Andromedae) is a star, a red giant in the constellation Andromeda.
There are two versions of the origin of the name Mirakh. The first is from the Arabic word المراق al-maraqq, meaning “lower back”, “buttocks”.
The second is from the Arabic mi "zar, “belt.” Both versions of the name are associated with the position of the star in the figure of the constellation. In Ptolemy’s Almagest, the star is described as “the more southern of the three above the belt.” In Latin, the star was sometimes called Umbilicus Andromedae (“Navel Andromeda").
Alamak(Almah, Almaah, Almaak, Al Maak, γ And / γ Andromedae / Andromeda Gamma) is the third brightest star in the Andromeda constellation, a multiple star system consisting of four components.
γ Andromedae is one of the most beautiful double stars visible in a small telescope. The main yellow-orange star γ1 +2.1 magnitude has a bluish companion γ2 with a magnitude of +4.84m at a distance of 9.6 arcseconds. γ1 is a bright giant of spectral class K3 with a surface temperature of 4500 K, exceeding the Sun in luminosity by 2000 and in radius by more than 70 times.
γ2 is a double star and consists of a pair of bluish main sequence stars with magnitudes +5.1m and +6.3m, orbiting with a period of 61 years. Due to the small distance between the components (no more than 0.5 seconds), only a large telescope can separate this pair. The brighter component of the pair is in turn a spectroscopic double star with an orbital period of 2.67 days.
The name of the star is usually associated with the Arabic al-canāq al-arđ̧, meaning an animal of the mustelid family. The translation of the name as “sandal” is associated with the location of the star in the constellation figure and is apparently erroneous. In Ptolemy's Almagest, the star is described as “the star above the left foot” of the female figure.
Andromeda's nebula(M31) is the most important object in the constellation Andromeda. This is a spiral galaxy with its satellites - the dwarf galaxies M32 and NGC 205. On a moonless night, it is visible even to the naked eye at an angular distance of just over 1° west of the star n Andromeda.
Although the Persian astronomer Al-Sufi observed the Andromeda Nebula back in the 10th century, calling it a “little cloud,” European scientists discovered it only at the beginning of the 17th century.
This is the closest spiral galaxy to us, approximately 2.2 million light years away. Although it resembles an elongated oval, since its plane is inclined only 15° to the line of sight, it is apparently similar to our Galaxy, has a diameter of more than 220 thousand light years and contains approx. 300 billion stars.
The constellation Andromeda was one of the 48 constellations listed in the 2nd century by the ancient Greek astronomer Ptolemy. Currently, it remains part of 88 modern constellations and is located north of the celestial equator (the projection of the Earth's equator into space). The name owes its origin to ancient Greek mythology.
Andromeda - daughter of the crowned couple Kepheus and Cassiopeia. This couple reigned in Ethiopia, and their young child was distinguished by extraordinary beauty. The girl’s appearance aroused the envy of the sea deities of the Nereids. They began to sleep poorly and wasted away before our eyes. To get out of mental depression, the Nereids turned to Poseidon (god of the seas) for help. And he sent a terrible sea monster to the Ethiopian shores.
It began to threaten the subjects of the crowned couple. Horror and confusion arose in the state. And then the oracle announced that salvation could only be achieved if the king’s daughter was given to the monster. The girl’s parents initially categorically refused, but then gave in to the persuasion of their subjects.
The beauty was placed on a high cliff, chained to it and left alone. The girl stood and waited for the sea monster to emerge from the abyss. And at this time, Perseus (the son of Zeus and Diana) flew past in his magic sandals. He saw Andromeda and immediately fell in love with her.
The beautiful creature, with tears in her eyes, told him about the horror that awaited her. Then the noble Perseus decided to help the girl, but made her promise that she would marry him. She happily agreed, and the two of them began to wait for the terrible monster. Finally, it appeared, and the noble hero pulled out the head of the Gorgon Medusa, whom he had killed, from his bag. The monster looked at her and immediately turned into stone.
As in any good mythical legend, good triumphed over evil. But there were some incidents. Andromeda was betrothed to Finney, brother of Cepheus. He appeared at the wedding of Perseus and Andromeda and demanded the return of the bride. But Perseus was not going to give up the beautiful bride. He took out the head of the Gorgon Medusa and turned Phineus into stone. This is the story of the times of magic and the gods. And we will involuntarily remember her, watching in the sky how brightly Andromeda flickers - the constellation, the legend of which is so beautiful and instructive.
This cluster of stars is one of the largest among its 87 brothers. Its area is 722 sq. degrees. It consists of 3 star chains. And their beginning is in the southern part of the northern sky near the Great Square of Pegasus. It is not difficult to find it. The easiest time to spot the constellation is in the fall. Between September and early December, the constellation Andromeda can be seen from early twilight until morning. In the evening, the asterism is in the east, a little closer to midnight - in the south. Closer to the morning it shifts in a westerly direction. First you will need to find a giant quadrangle - the Pegasus Square.
To the left of the Square you can see a chain of stars of the same luminosity. These are precisely the stars of the Andromeda constellation. You can find the desired asterism in another way. First, find the constellation Cassiopeia, it looks like the letter M or W, depending on the position of the asterism in the sky. The Andromeda stars are located directly below this “letter”. With the onset of December, the constellation Andromeda shifts to the west. Closer to spring, the asterism is already in the northwest direction. And with the approach of summer, it comes out only at dawn, and it is quite difficult to notice it.
The constellation in question is located at a great distance from the plane of the Galaxy, so there are no clusters or nebulae of the Milky Way in it. But the cluster of luminaries itself contains a lot of visible distant galaxies. The most famous is the Andromeda spiral galaxy, or the Andromeda Nebula, or M31, or NGC 224. This is the largest star formation of the local group. And it includes the Milky Way, the Triangulum Galaxy and 30 other small galaxies.
There are about 800 billion stars in this nebula. And our native Galaxy can boast only 400 billion stars. At the same time, these two cosmic giants are approximately equal in mass. Although it was previously believed that the Milky Way makes up only 80% of the distant Andromeda Nebula. It is noteworthy that the two galaxies are moving towards each other and should meet in more than 3 billion years. As a result, a giant elliptical galaxy is formed.
The nebula is visible to the naked eye, and it is located at a distance of 772 thousand parsecs from the Earth. Since ancient times, people have observed it in the form of a small luminous oval spot. However, this speck has a diameter of more than 150 thousand light years and contains a huge number of stars.
There are also many globular clusters in the galaxy. These are stars tightly bound by gravity, orbiting as a satellite around the center of the galaxy. There are 460 such clusters in total. Each of them contains approximately 300 thousand stars. It is possible that these are the cores of dwarf galaxies that were once absorbed by Andromeda.
The galaxy has dwarf satellite galaxies. These are relatively small star systems that contain only a few billion stars. The most famous of them are M32 and M110. They were once spiral, but the Andromeda Nebula, with its tidal forces, destroyed the arms and absorbed them.
Thus, the Andromeda constellation includes the most diverse and countless number of space objects. There are 163 stars in total. These include supernovae, variable stars, and planetary systems. All of them make up a majestic cluster, named after a beautiful girl from the mythology of the ancient Greeks.
The constellation Andromeda became the object of observation by many astronomers in 1885. Then it was lit up by a supernova explosion. It became the first such object found outside the Milky Way. Supernova S Andromeda is located in the galaxy of the same name and is still the only such cosmic body in it. The luminary reached its maximum brightness on August 21-22, 1885 (it amounted to 5.85 m). After six months it decreased to 14 m. Today, S Andromeda is classified as a Type Ia supernova, although its orange color and light curve do not match the accepted description of such objects. The Andromeda constellation, photos of the objects that make it up, and an image of a neighboring galaxy appear quite often in the media. And this is not surprising: the vast space occupied by the celestial pattern can tell a lot about the laws of space and the interconnection of its individual parts. Many telescopes are aimed here in the hope of obtaining new information about distant objects.
What does it consist of and what does the constellation Andromeda look like? , as well as some interesting facts and a brief description, you can learn from this article.
Andromeda ( Andromeda) is a constellation located in the northern hemisphere of the sky. It is clearly visible throughout Russia. The best conditions for its visibility occur annually in September and October. To find a constellation in the sky, it is enough to find the Great Square of Pegasus in the southern side of the sky, in the northeastern corner of which is the star Alferats (which is the α of Andromeda). It is from it, to the northeast, towards the constellation Perseus that three chains of stars diverge, which make up the constellation Andromeda. In the picture below you can see the three main brightest stars of the constellation: Alceraz, Mirakh and Alamak (double star)
picture of the constellation Andromeda
According to the myths of Ancient Greece, Andromeda was the daughter of the king and queen of Ethiopia, Kepheus and Cassiopeia. Andromeda was sacrificed to a sea monster. which devastated the country, but was saved by Perseus. According to legend, after her death Andromeda turned into a constellation.
