Constellations are guides that have accompanied a person since ancient times. According to them, people could navigate along the way. Once the constellations were those figures that formed stars among themselves. Now so-called certain territories of the celestial sphere. In 1930, the official number of constellations was fixed - 88. Of this number, 47 were discovered and described BC. But the names that they were given then are used up to the present day.
The number of stars in the visible sky
A group of stars, united by one name, is called a constellation. Thanks to the observations of astronomers, it was possible to find out that their location in the sky is gradually changing. The night sky creates the illusion of stars randomly located next to each other. About 3 thousand stars are located in the visible part, and about 6 thousand stars in the whole sky
How to get the names of a group of stars
For ancient astronomers, a group of stars, united by one name, served to ease the search for less bright luminaries. Bright stars united in certain groups. Usually they received the names of various animals. For example, Scorpio, Ursa Major and Ursa Minor, constellations of Upper and Minor Dog. Also, a group of stars, united by a common name, could get a name in honor of one of the heroes of ancient myths - for example, the constellations Perseus, Andromeda and others were named. Since the beginning of the XVIII century, the brightest of the stars of some constellations began to be called the letters of the Greek alphabet. In addition, about 130 separate bright stars got their names. And for luminaries of lower brightness to this day, researchers use letter designations.
Constellation observation
The world around us, stars and constellations will be especially interesting to the attentive observer. If you watch the night sky for several hours, you can see how the entire celestial sphere, including the stars, moves smoothly, as if it rotates around an invisible axis. This type of movement is called daily allowance. The stars in the firmament move from left to right. Stars, like the moon and the sun do, rise in the east. They reach their maximum height in the southern part. Sunset is from the west.
The largest constellation in the sky
The largest group of stars united by one name is the constellation Hydra. It is located in the southern hemisphere. The name of this constellation translated from Latin means "water snake." Hydra was discovered by the ancient Greek scientist Ptolemy in the II century BC. e. There is a famous myth according to which the constellation of Hydra is identified with the snake brought to the god Apollo by the raven: next to Hydra is also the constellation Raven. According to myth, Apollo sent a raven to get water. The raven brought the water snake as an apology for returning too late. The ancient Greek god was very angry and threw a bird, a bowl and a snake into the sky in a rage, where they turned into constellations - Raven, Crater and Hydra.
Another magnificent group of stars united by one name is the constellation Orion. It is believed that it is no less beautiful than the constellation Ursa Major. In the night sky, it is very easy to find it in the so-called “Orion belt” - three blue-white stars, located slightly inclined in a row. If you draw an imaginary line through the "Orion belt", then its lower end will indicate the brightest star of the night sky - the star Sirius. Around these three stars are located and brighter stars, as well as the cosmic nebula Orion. It can be easily seen even with binoculars. The brightest star in Orion is Betelgeuse, whose name in Arabic means "armpit."
Constellations of the zodiac
The universality of the names of stars and constellations, around which the Sun makes its visible year-long path, was called the Zodiac. There are thirteen such constellations in total, but researchers use twelve of them by the number of months in a year. The division of the sky into 12 spheres appeared in ancient Babylon in the 5th century BC. e. Many people associate the Zodiac primarily with astrology. But in fact, the signs of the zodiac belong to the field of astronomy. These constellations lie on the line of the ecliptic, along which the Sun makes a visible journey 365 days a year. It lingers around each constellation for about the time that we call the month.
Pleiades constellation
For everyone, the answer to the question “What is the name of a group of stars united by one name?” Is already obvious. Astronomers combine celestial bodies into groups called constellations. But scientists are sometimes seriously mistaken in estimating the size of these star clusters. An example of this is the idea of the constellation Pleiades. It was once believed that in this group there are only 7 stars. The ancient Slavs called them differently: “Seven Sisters”, “Stozhary” and so on.
But at present, both foreign and domestic astronomers know that there are not seven Pleiades in the sky. This cluster has thousands of stars, of which only fourteen are accessible to the human eye. They came from one molecular cloud. These stars are close to each other in composition and age. Scientists believe that the age of the Pleiades cluster is about 115 million years. This constellation can be easily observed in the latitudes of Russia, Ukraine and Belarus. The Pleiades are located near the Solar System. Fly to this constellation - 410 light years.
Bright constellation Centaurus
And the closest to the solar system is the constellation Centaurus. It is in it that mankind hopes to find brothers in reason. This cluster consists of only three stars: Centaurus A, Centaurus B and Proxima Centauri. Alfa Centauri is 2 billion years older in age. The light emitted by these stars reaches the earth observer in 4.3 years. It is here that the star closest to the Sun is located - this is Proxima Centauri. However, after 9 thousand years this place will be taken by Barnard, belonging to the constellation Ophiuchus. The constellation Centaurus was also discovered by Ptolemy. It was named after the centaur - half-horse half-man. The constellation Centaurus is very bright and is one of the largest in the sky.