Residents of Russia and neighboring countries cannot observe the constellation Circulus. It is located in the Southern Hemisphere. Its peculiarity lies in the fact that it is small, taking 85th place among 88 that currently exist. The area of ​​the constellation is 93 square meters. gr.

It is believed that the constellation is one of the most inconspicuous in the sky. Indeed, it is very small, lying to the west of the Triangulum and the Southern Triangle, in close proximity to Alpha Centauri. The stars in it are dim, at least 4- magnitude. Residents of the Southern Hemisphere can see it on a moonlit night. About 20 stars are formed in the sky, which do not have a clearly defined structure. It is scattered in a chaotic manner. Therefore, it is impossible to see the compass in them. In astronomical maps, they simply indicated the place (region) that the constellation Circulus occupied. As a designation, Alpha was usually used, the first in brightness (as far as possible in the Compasses).

Story

An astronomer named Nicola Lacaila placed it in his atlas. The first mention of the constellation dates back to 1754. For several years, the constellation Circulus was not named in any way. In 1973, it received the name le Compas (translated from French. Compasses), information about it was published in a special catalog. But this happened after the death of the astronomer. In old Russian books you can find a different name - Bussol.

It is noteworthy that, naming the constellations in this way, the astronomer did not try to give the name a semantic load. He just needed to somehow structure the stars of the Southern Hemisphere. Many constellations discovered by him also have peculiar names: Square, Octant, etc.

Objects

The bright star is Alpha, a variable with a magnitude of 3.18. A double object that has a companion. It has a spectral-double brilliance of 8.8 m.

Less bright - Beta, with a magnitude of 4.1. It is located at a distance of 93 light years from Earth. Beta is ranked among the blue giants.

Gamma is a double object, includes blue and yellow star. Hence its duality. It is removed from the Earth at a distance of 508 light years.

Trying to find the constellation Circulus, you need to rely on Alpha Centauri. It is next to it that the Compass is located, in which about 20 stars are observed, the brightest is Alpha.

Circulum Galaxy

The galaxy is a spiral type, located at a distance of 13 light years from Earth. There is an assumption that there is a massive black hole in the core of the Galaxy. Scientists believe this is so, because the large vortex of the Galaxy lets out gases from the core, and at an unusually high speed. The vortex itself is made up of stars as well as intergalactic dust.
One of the most interesting objects in the Galaxy constellation is the nebula. She was nicknamed "The Black Widow". These are two large bubbles, consisting of gas and dust. The bubbles are connected to each other by a bridge. In the jumper one can observe quite big stars, they are young compared to those located in the neighborhood. The accumulation of newcomer stars creates the so-called sunny wind blowing bubbles. Scientists believe that over time, the Black Widow Nebula will become a cluster of stars, and very massive.

Compass X-1

Located at Milky Way. The system consists of a neutron star, which was formed as a result of the breakup of a new and regular star. Compasses X-1, according to its characteristics, has a strong gravitational field, pulling out hydrogen molecules when neighbors approach. This hydrogen envelops neutron star, forming an accretion disk. The layers of this disk approach the star over time.

Neighbours

Despite the fact that the constellation Circulus is inconspicuous in area, it does not differ in anything outstanding, it boasts the presence of famous and interesting neighbors. Nearby is the Bird of Paradise, Centaurus, Wolf, Corner and Southern Triangle.

The square, also described by the astronomer of the same name, and named by him, slightly outperforms Compasses in terms of area, taking 74th against 85th place. By analogy with the Compasses, the Square has a peculiar name, not tied in meaning, and is also devoid of bright stars.

Something to be proud of is Alpha Centauri. The three brightest stars with amazing brilliance are included in this amazing constellation, which is closest to the earth. By the way, it will help astronomy lovers to find an inconspicuous compass in the sky. In the process, you need to focus on Rigel and Hadar, located on east side Alpha Centauri. If you draw a line through them westbound, you can see the Compass.

Interestingly, the Galaxy of interest to us was discovered relatively recently: in 1975. Earth is separated from it by 15 million light years. The late discovery of the Galaxy by specialists is explained by the fact that earlier the dust of the Milky Way prevented it from being detected.

The constellation Circulus is perhaps the smallest object in the entire starry sky. Located territorially in the Southern Hemisphere, the Compass occupies only 93 square degrees of its area. This indicator is only 85 among the 88 constellations that exist today. In such a small area, the observer will see about two dozen Circulus stars.

Constellation Circulus, view in the program of the planetarium Stellarium

Despite the obvious modesty of its area, the compass, nevertheless, acquired enough large quantity star neighbors. So, in close proximity to it, the constellations of the Fly, the Bird of Paradise, the Wolf, the Centaurus, the Southern Triangle and the Square are located. The chaotic arrangement of the rather faint stars of Circulus does not form any special geometric shapes. In this regard, when depicting the Compass on star charts since ancient times, the restriction of the area occupied by the constellation, and the designation of its brightest star, has simply been used. This object is not available for observation on the territory of the Russian Federation.

Star Features of the Compass

constellation alpha

Starting the description of the constellation Circulus, it is worth, as always, to note its brightest stars. Alpha Circulus has the strongest stellar brilliance. It's splendid variable luminary type Alpha-2 in the Compass with a magnitude of 3.18m. Alpha is a paired system located just 53 St. years from our planetary home. Alpha Circulus, together with a faint companion star, belong to spectral class F1Vp.

The second in apparent brilliance in the Circus is the luminary main sequence beta star. It belongs to the A-class and has a magnitude of 4.07m. There is a distance of 97 light years between the object Beta Circulus and the planet Earth.

Gamma Circuli is considered the third brightest star in the constellation. It is a binary system with an apparent magnitude of 4.48m. Opposite in spectrum stars of class B5III + F8 yellow and blue flowers are a very close couple. The gamma of the constellation in question is 508 St. years.

Galaxy of the same name in Circulus

The Circulus Galaxy or ESO 097-13

Among the objects of deep space in given constellation there is one galaxy that has the same name with it. The Circulus galaxy was discovered a little more than 30 years ago in 1975, despite the fact that our planet is separated from it by some 15 million light years. years. So late opening this object can be explained by its obscuration by the dust of our Milky Way. The galaxy has a twelfth magnitude and can be observed already in a small telescope. In its very center there is an active core, in which very strong and powerful star formation processes take place.

Some historical data

The constellation Circulus undoubtedly belongs to the new constellations. Like the appearance of many other celestial constellations, the discovery of the Compass in the starry sky can be associated with the name of the French sky explorer Nicolas Louis De Lacaille. The first description of the constellation was made by him in 1756. Wanting to fill the void between the constellation of the Southern Triangle and the legs of the constellation of Centaurus, Lacaille introduced a new object, which in navigation is two dividing compasses, thanks to which distances are measured. The name of the constellation was Latinized in 1763.

located in southern hemisphere sky and can be easily found next to Alpha Centauri. Rather, one can easily detect the region of the sky where it is located - because there are no special configurations of noticeable stars in it. In Circulus, without the involvement of special equipment, you can visually see about twenty stars, but only one of them is brighter than the fourth magnitude.

Introduced by the French astronomer Nicolas Louis de Lacaille in 1756. No special semantic load the name of the constellation does not bear - the scientist just had to group the stars near the south pole of the world. The rest of the constellations named by him also bear the names of the instruments: Square, Octant, Microscope.

The most bright Star- Alpha Circulus. This is double star, whose main component has a magnitude of 3.2m. The second component has a magnitude of 8.8m and is a spectroscopic double. Alpha Circulus - type variable Alpha Hound Dogs. The second brightest is Beta Circulus, a blue giant whose brightness is 4.1m.

Spiral Galaxy Compass

There are several interesting extragalactic objects in the Circus. The Circulus Galaxy is a spiral galaxy located at a distance of 13 million light-years from us. The core of the galaxy is ejecting matter from itself at an enormous speed, which led to the assumption of the existence of a massive black hole in the center. It belongs to the so-called Seyfert galaxies with active nuclei. Another interesting object- The Black Widow Nebula. It consists of two giant bubbles of gas and dust, connected by a bridge, in which massive young stars are visible. It is believed that it is the young cluster that creates the "solar wind", which blows the "bubbles". Over time, the Black Widow will turn into a massive star cluster.

Nebula Black Widow

It was marked on the map only in order to arrange the array of stars around South Pole sky. But is this a reason not to explore it on one of the moonless nights away from the city lights?

Phoenix is ​​the southern constellation and is not observed from the territory of the CIS. It is surrounded by the constellations of Eridanus, Toucan, Crane and Sculptor.

If nothing interferes with observations, up to 40 stars can be distinguished with the naked eye in the Phoenix constellation, but only six of them are brighter than the fourth magnitude. Four stars form a rhomboid, from the western top of which an arc of three fainter stars “emerges”. It is very difficult to see in this geometric figure that mythical Phoenix bird, which burned itself once every five hundred years to be reborn from the ashes young and renewed, in the form of which this constellation was depicted in ancient astronomy manuals.

This myth is associated with the cult of the Sun. In the ancient Egyptian city of Heliopolis (city of the Sun), the majestic temple of the Phoenix bird towered. According to legend, after self-immolation and rebirth, the Phoenix bird flew east to Arabia or India.

Chameleon - small southern constellation located in the southern celestial hemisphere. Surrounding the chameleon are the constellations Bird of Paradise, Octant, Table Mountain, Flying Fish, Carina, and the Fly.

If nothing interferes with observations, about 20 faint stars can be seen in this constellation with the naked eye, but only four of them approach stars of the fourth magnitude. They form one elongated rhomboid. With all the desire, it is difficult to imagine the Chameleon in this geometric figure, in the form of which this constellation was depicted on ancient star maps and in star atlases.

The compass is perhaps the smallest constellation in the southern hemisphere. It is surrounded by the constellations of the Bird of Paradise, the Southern Triangle, the Fly and the Centaurus.

With excellent visibility in the constellation Circulus, twenty extremely faint stars can be seen with the naked eye. They are arranged so randomly that they do not form any geometric figure, and even with a maximum of fantasy, one cannot see the image of a compass in them. Therefore, on old star maps and in star atlases, the area that the constellation occupied was only delimited, and the brightest star in it was indicated ( alpha Compasses, which has a third magnitude), but no image of a compass was placed.

Star alpha The circle is double. Main star has the value З m ,4. At an angular distance of 16 "from it is a satellite (value 8 m, 8). But the satellite, in turn, is a spectral binary star. Thus, alpha Compasses refers to ternary systems.