To use astronomical instruments, you must be able to accurately find the necessary stars and planets on the celestial sphere.
Observing the starry sky, one cannot help but notice a wide variety of stars. Many stars stand out because of their brightness or color. Among the large number of stars, separate groups of stars stand out, having characteristic outlines and called constellations.
Constellations, participating in the daily rotation of the celestial sphere, retain their relative positions relative to each other and the outlines of their characteristic figures. The presence of such features makes it easy to navigate among thousands of stars, despite the apparent randomness in their location. Most characteristic features, by which they are found navigation stars, are the configurations of the constellations, the relative positions and the apparent brightness of the stars.
In order to find the desired star in the sky, they first find the constellation to which it belongs, and then, knowing the location of the desired star in this constellation and its apparent brightness, they look for the star. The brightest stars in constellations serve as reliable guides to locating fainter stars.
According to the decision of the International Astronomical Union, the entire sky is divided into 88 constellation areas, of which more than 60 can be visible from the territory of the USSR. Each of the constellations has a name. Most of the constellations received their names in ancient times and are associated with legends and myths.
The brightest stars of each constellation are designated by letters of the Greek alphabet, usually in order of decreasing apparent brightness. The brightest star in the constellation is designated by the letter a, the next in brightness by the letter (3, etc. In some constellations, this order of designating stars is violated. The brightest stars of the constellations, in addition to letter designations, have their own names. So, for example, star and the constellation Lyra is called Vega, the star of the constellation Orion is called Rigel.
In the Northern and Southern Hemispheres, certain navigation stars are used, for which tables of altitudes and azimuths have been compiled.
Navigation stars used in the Northern Hemisphere are given in Table. 2.1.
The easiest way to find the stars you need for observations is from reference constellations that have familiar outlines. The most expressive constellations serve as starting points, allowing you to move from them to neighboring constellations and stars.
Table 2.1. Navigation stars used in the Northern Hemisphere
Finding navigation stars visible in the Northern Hemisphere is carried out according to the following rules. The starry sky is conventionally divided into three sections (Fig. 2.1).
In the first part of the sky are the constellations Ursa Major, Ursa Minor, Bootes, Virgo, Scorpio and Leo.
A well-known constellation in this area is the constellation Ursa Major. From there they begin to find other constellations. The seven brightest stars of this constellation form the characteristic shape of a ladle with a handle, the most memorable figure in the starry sky. The third star from the end of the handle is the navigation star Alioth. It should be borne in mind that the handle of the bucket due to the rotation of the starry sky in different times has a different direction to the horizon line.
To find North Star you need to mentally draw a straight line through the two outermost stars of the bucket of the constellation Ursa Major in the direction of the outer part of the bucket, and then on this line plot five distances between the indicated stars. At the end of the delayed distance, Polaris will be revealed, the brightest star, part of the constellation Ursa Minor. The seven stars of this constellation form a small bucket with a handle, at the end of which is the North Star. This star is very important because of its special position in the sky. It almost exactly coincides with the celestial pole, and therefore you can always use it to indicate the direction to the north and determine the latitude of the observer. Most of the stars of the small dipper are faint.
Rice. 2. 1. Rules for finding navigation stars in the Northern Hemisphere
Among them, only the two outer stars of the bucket stand out. They are called the “guardians” of the pole because they walk around the pole like sentries.
To find the navigation stars Arcturus and Spica, you need to continue with your gaze the arched line of the handle of the Ursa Major bucket. First, this line will pass through the constellation Bootes, which has the shape of a parachute icon, which includes the star Arcturus, the brightest not only in this constellation, but in the entire first part of the sky. Arcturus is a very prominent star with an orange tint. Further along the continuation of the arc-shaped line is the only bright star Spica, part of the large constellation Virgo, which consists mainly of faint stars.
To find the star Antares in the constellation Scorpio, you need to draw a straight line through the stars of the handle of the Big Dipper. This line will pass by the clearly visible crescent-shaped constellation of the Northern Crown.
The star Antares is located at a distance approximately twice as great as the distance from the Big Dipper bucket to the Northern Crown.
To find the star Regulus, you need to draw a straight line through the two stars of the Ursa Major bucket closest to the handle, in the direction opposite to the North Star. Having plotted a distance on this line, approximately 1.5 times greater than the distance from Ursa Major to the North Star, they look for the star Regulus of the constellation Leo, which has a trapezoidal shape.
In the second section of the sky are the constellations Orion, Taurus, Auriga, Gemini, Canis Minor and Canis Major. In this area, the reference constellation is the constellation Orion, which is almost as well known as the constellation Ursa Major. This constellation is very rich in bright stars. There are so many bright stars in no other constellation: five stars of the second magnitude and two of the first. Its four bright stars form a trapezoid, inside which three also bright stars, called Orion’s belt, are located nearby. The two brightest stars of this constellation, located in opposite corners of the trapezoid, are navigational.
The star that is closer to Polaris is called Betelgeuse, and the star opposite it is called Rigel. Betelgeuse is a red star and Rigel is white.
On the continuation of the spiral line begun in Orion's belt, in a counterclockwise direction, the stars Aldebaran (Taurus), Capella (Auriga), Pollux (Gemini), Procyon (Canis Minor) and Sirius (Canis Major) are located in sequence - the brightest star in the whole sky.
The third section of the sky contains the constellations Lyra, Cassiopeia, Cygnus, Eagle, Pegasus, Andromeda, Aries and Southern Pisces. In this area, the constellation Cassiopeia and the brilliant star Vega of the constellation Lyra stand out. The star Vega is the brightest star in the third region of the sky.
The constellation Cassiopeia, which has the outline of the Latin letter W, although it does not contain a navigation star, is a characteristic landmark.
Vega is located on the continuation of a straight line drawn through two stars at the base of the handle of the Ursa Major bucket in the direction opposite to Regulus. Near Vega, four faint stars of the small constellation Lyra form a characteristic parallelogram figure.
Near the constellation Lyra are the constellations Cygnus and Aquila. The brightest stars of the Cygnus constellation form a cross shape known as the Northern Cross, at the top of which the bright star Deneb stands out.
The constellation Aquila resembles the figure of an airplane. Its brightest star is the navigation star Altair. Altair, Vega and Deneb form a large summer triangle, known to all navigators.
If you draw a straight line through the two outermost stars of the bucket, Ursa Major and Polaris, it will pass through the constellation Pegasus. A group of stars in the constellations Pegasus and Andromeda form a bucket that is significantly larger than the bucket of Ursa Major. At the base of the handle of this ladle is the star Alferaz (Andromeda). On a clear and moonless night, not far from the star Alferats towards the constellation Cassiopeia, you can see the Andromeda nebula, the closest galaxy to us.
To find the star Fomalhaut of the constellation Southern Pisces, you need to continue a straight line going from Polaris through the constellation Pegasus.
To find the star Hamal, which is part of the constellation Aries, you need to draw a straight line from the North Star past the easily identifiable constellation Cassiopeia towards the constellation Andromeda, near which the star Hamal is located.
When flying in the Southern Hemisphere, 24 navigation stars are used, of which 16 are the same as those used in the Northern Hemisphere and 8 additional ones: Hamal (Aries), Canopus (Argo), Achernar (Eridani), Peacock (Pavlina), Yuzhny Cross, and Centauri, and Southern Triangle and 8 Sagittarius.
In the Southern Hemisphere, of the total number of navigation stars, only two are not used - Polaris and Betelgeuse.
Navigation stars located in the Southern Hemisphere usually begin to be found from an easily identifiable group of constellations Carina, Puppis, Compass and Sails, which used to be part of one large constellation Ship of the Argonauts (Fig. 2.2).
In the constellation Carina, the yellow star Canopus stands out, which is second only to Sirius in brightness. The bright stars Sirius, Canopus and Rigel form a triangle that stands out when you first look at the sky.
A famous constellation of the Southern Hemisphere is also the famous constellation of the Southern Cross. Its longer crossbar points almost exactly to the South Celestial Pole, which, unlike the North Celestial Pole, is not marked by any star. The Southern Cross constellation is small, but consists of bright stars. The brightest star is the navigation star.
In the same part of the sky there is a large and expressive group of stars that are part of the constellation Centaurus. In this constellation, two stars stand out, located at a short distance from each other. The navigational one is Centauri, which is brighter. Not far from this star is the noticeable constellation Southern Triangle with the navigation star a.
Constellations that have highly visible configurations and contain bright stars include Pavo and Sagittarius. The constellation Pavo contains the navigational star Peacock, and the constellation Sagittarius contains the star. These stars with the navigation star a of the Southern Triangle form an easily distinguishable triangle. These three stars have approximately the same brightness and stand out among the fainter stars in this part of the sky.
Rice. 2.2. Rules for finding navigation stars in the Southern Hemisphere
A very large part of the sky of the Southern Hemisphere is occupied by the large, but weak and shapeless constellation Eridanus. It stretches across one of the most desolate areas of the sky. Its only bright star, Achernar, is a navigation star. Due to the fact that in this part of the sky, except for the Achernar star, there are no other bright stars, it is necessary to use the Hamal star, located in the Northern Hemisphere near the equator, although it is not very bright.
Almost all of the listed navigation stars are located on the same arc-shaped line going around the South Pole of the world.
In order to master the considered rules for finding navigation stars, it is necessary not only to study them, but also to conduct a series of trainings on applying these rules directly in the starry sky.
The most rational way to study the starry sky is to study it in a planetarium, where you can simulate the appearance of the starry sky for any time of day and different latitudes. Each navigator must train himself so as to find the necessary constellations and stars not only when the entire sky is visible, but also its individual sections. To accurately find and identify navigation stars, in addition to the peculiarities of the configurations of the constellations and their relative positions, it is necessary to take into account the color and magnitude of the stars being searched and the stars located nearby.
All considered navigation stars can be used for aircraft navigation. However, it should be borne in mind that the possibility of their visibility in the sky depends on the latitude of the observation site, time of year and day.
In the middle of the night, those constellations that are located in the part of the sky opposite the Sun are accessible to observation. Knowing the dates of the location of the Sun at the main points of the ecliptic, it is possible to easily determine the constellations located on the night side of the starry sky, visible at a given time of year, using the star maps attached to the AAE.
Finding planets follows different rules than finding stars, since they do not have a permanent place in the sky. They continuously wander among the stars. Of the four planets used for aircraft navigation, usually one is visible, often two, sometimes three, and sometimes all four are visible at the same time. Planets are always observed near the ecliptic, which is easiest to find in the sky using the navigation stars Antares, Crshka, Regulus and Aldebaran (see Fig. 2.1). These stars are located almost on the ecliptic and often two or even three are visible at the same time. One or two planets are observed not far from the line passing through the indicated stars.
The position of the planets used for aircraft navigation on the date of observation is determined according to special diagrams attached to the AAE. Knowing in which part of the sky the planets are located, they are always easy to recognize by their even, non-flickering light and brightness. This is how they differ from stars.
Venus is much brighter than all the stars. It shines with a silvery-white light. Observed after sunset or before sunrise. At its maximum distance from the Sun, it sets no later than 3-4 hours after sunset or rises no earlier than 3-4 hours before sunrise.
Mars is easy to recognize by reddish tint. The brightness of Mars varies greatly depending on its distance from Earth. Sometimes it is significantly brighter than Sirius, and sometimes its brightness fades to second magnitude and it is observed as Polaris.
Jupiter has a yellowish color. It is less bright than Venus, but also shines brighter than all the stars.
Saturn is fainter than Jupiter in brightness. Its apparent brightness is approximately equal to that of first magnitude stars. It, like Jupiter, has a yellowish color. The visibility of planets depends on their position relative to the Sun. If the planet is nearby or in the same constellation as the Sun, then daylight will not allow her to be observed. Therefore, when choosing planets for aircraft navigation, it is always necessary to take into account the relative positions of the planets and the Sun.
Let's look at an example of how to find out which constellations and planets will be observed on a given night, how to find and identify the desired star. Date of flight: January 5, 1975. Time of use of astronomical aids from 22:00 to 24:00. Geographical latitude of the observer: 50° N.
It is known that the visible picture of the starry sky depends on the position of the Sun on the ecliptic. According to the daily AAE tables, we find that on January 5 the right ascension of the Sun is 286°. Using Appendix 3, we determine that the Sun on the specified date is in the constellation Sagittarius. Therefore, this constellation and the constellations adjacent to it will be in the sky during the day. Under normal conditions they cannot be seen. At night, those constellations that are located in the part of the sky diametrically opposite to the Sun will be visible, that is, constellations whose right ascension differs by 180° from the right ascension of the Sun. These will be the constellations Gemini, Auriga, Taurus, M. Canis and Orion.
Suppose you want to find the navigation star Pollux. This star is part of the constellation Gemini, characterized by its two bright stars - Pollux and Castor. In order not to confuse them, you need to look at the table given in AAE and find out what magnitudes these stars have. The magnitude of Pollux is 1.21, and that of Castor is 1.99-2.85. From these data we see that the star Pollux is brighter than the star Castor. In addition, it is known that Pollux is a yellow star and Castor is white. And finally, the star Pollux is closer to the constellation M. Canis than the star Castor. All of the above features help to find and accurately identify the star Pollux.
According to the diagrams given in AAE, we learn that on January 5 the planet Saturn is located in the constellation Gemini. Knowing the declination of this planet and the star Pollux, as well as the latitude of the observer, we find that the height of these luminaries at the moment of their culmination does not exceed 70°. Therefore, they are convenient to observe for the given conditions in the example.
Navigation stars
stars of apparent magnitude, used by navigators and pilots when determining the location of ships and aircraft beyond the visibility of earthly landmarks.
Source: "Architectural Dictionary"
Construction dictionary.
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Books
- Guiding stars. Navigation Secrets of the Pacific Islanders, D. Lewis. When it comes to the elements, we have a lot to learn from those who spend their entire lives in close proximity to them. David Lewis, the famous scientist, traveler and writer, described...
Brilliant achievements Soviet science and technology in the field of space flight - the world's first satellite, the first rocket on the Moon, the first rocket on the way to Venus, the first satellite spacecraft and the first person on board a spacecraft to fly into the Universe - attract everyone more people to the study of practical astronomy.
The book offered to the attention of readers tells about the great practical importance for a person of orientation by the stars and other celestial bodies, how to independently find the brightest constellations and stars in the sky, how to determine the time by the stars and the Sun, as well as about astronomical methods of orientation to terrain, determining the course and place of the aircraft in flight, orientation during space flight.
Some factual material ( general information about the Galaxy, about the movement of the Sun, Moon and planets, the main systems of celestial coordinates) expands the general horizons of the reader.
The book summarizes the latest data from Soviet and foreign aviation astronomy in a popular scientific form. It is written in accessible language and is intended for a wide range of readers - flight personnel, cadets and students of secondary and higher education. educational institutions Air Force, Civil Air Fleet and DOSAAF, as well as persons interested in issues of orientation by celestial bodies.
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STARRY SKY
On a clear, moonless night, both bright stars are visible above our heads, immediately attracting attention, and less bright ones, which are barely visible to the naked eye. On one side of the sky there are some star patterns, on the other - others (see appendix). Some groups of stars with their designs resemble some kind of figure: a ladle, a cross, a sickle, etc.
The brightest stars differ from each other and in color. Due to differences in the surface temperature of stars, some of them emit white light, others yellowish, others reddish or orange, etc.
From the Earth it seems that the starry sky is one whole, like inner surface a huge ball constantly rotating around an axis. The rotation of the firmament, in which the stars are motionless one relative to the other, can be noticed within one to two hours. In one day, the vault of heaven makes a complete revolution. If you photograph this rotation of the starry sky, the stars in the picture will draw lines corresponding to their movement. The rotation of the starry sky near the celestial pole is especially clear (Fig. 13).
But the rotation of the celestial sphere is apparent. In fact, the Earth rotates around its axis.
Due to the rotation of the Earth around its axis, the apparent daily rotation of the celestial sphere around the axis of the world occurs at an angular velocity equal speed rotation of the Earth, but in the opposite direction. In this case, each star describes a small circle; the planes of these circles are parallel to the plane of the celestial equator.
At different geographic latitudes, the pattern of apparent rotation of the firmament is different. In mid-latitudes (Fig. 14, a), stars located near the North Star describe a circle around it without going beyond the horizon. For a given latitude, these are the so-called non-setting luminaries. Some stars appear over the horizon and, having passed across the sky, disappear. The luminaries located near the south pole of the world are not visible at all, since during rotation they do not emerge from the horizon. These are non-rising luminaries.
From Fig. 14 it is clear that the non-setting luminaries in the Northern Hemisphere will be those with? ? (90° - ?), non-ascending - those with? ? - (90° - ?). The conditions for the rising and setting of the luminaries will be
- (90° - ?) ? ? ? (90° -?).
As the latitude of the observation site increases, the number of non-setting, and therefore non-rising, stars increases.
At the North Pole of the Earth (Fig. 14, b) only one celestial hemisphere can be observed. There, the celestial pole coincides with the zenith, the true horizon with the celestial equator, and the horizontal coordinate system with the equatorial one. There are no phenomena of rising and setting stars. All visible stars revolve around Polaris parallel to the true horizon. The altitudes of the stars are constant and equal to their declinations, and the azimuths vary uniformly from 0° to 360° (to measure the azimuth you need to move slightly away from the pole point).
At the earth's equator (Fig. 14, c), the entire celestial sphere is available for observation. All stars rise and set, and the direction of their movement is perpendicular to the plane of the true horizon. The polar star is visible near the point of north, that is, at the very horizon in the northern direction.
Based on brightness (brilliance), stars are divided into groups in accordance with stellar magnitudes. 1st magnitude stars are those that are 100 times brighter than the faintest stars visible with normal naked eye vision; stars whose brightness is 2.5 times less than 1st magnitude stars are considered 2nd magnitude stars, and those whose brightness is 2.5 times weaker than 2nd magnitude stars are considered 3rd magnitude stars etc., i.e., each subsequent group is 2.5 times weaker than the previous one in brightness. The faintest stars visible to normal naked eye vision are 6th magnitude stars.
For more precise definition brightness, fractional magnitude designations are used. For example, the magnitude of Polaris is 2.1; Aliota 1.7; Run 0.1, etc. There are stars whose magnitude is less than one and even less than zero.
The brightest stars in the sky are Sirius and Canopus. Their magnitude is expressed as a negative number: for Sirius it is equal to -1.3; Canopus has -0.9. Ten stars range in magnitude from zero to one. These are Bega, Arcturus, Capella, Procyon, Altair, Betelgeuse, Rigel, Achernar, ? And? Centauri. There are 41 stars brighter than stars of the 2nd magnitude, brighter than the 3rd - 138, brighter than the 4th - 357, brighter than the 5th - 1030 stars, etc. Although modern telescopes allow you to see stars only up to the 23rd magnitude, through mathematical calculations it has been established that there are stars of at least the 50th magnitude and that greatest number stars of 27th magnitude. A person with normal vision sees about 2,500 stars (up to 6th magnitude) above the horizon at the same time.
The brightness of the brightest celestial bodies, expressed in stellar magnitudes, is: Sun -26.7, Moon (full) -12.6, Venus -4.3, Mars -2.8, Jupiter -2.5 (stellar magnitudes of the planets are given according to their greatest brilliance).
The starry sky is conventionally divided into sections various shapes, called constellations. Each of them has its own name. These names were given to the constellations back in ancient times and reflect the similarity of the configurations of individual groups of stars with the outlines of certain objects, with the figures of certain animals and fairy-tale heroes. In this regard, on ancient star maps, constellations were depicted in the form of contours of corresponding figures.
In each constellation, the bright stars are designated by letters of the Greek alphabet, and the brightest of them also have their own names. Less bright stars are often designated by letters of the Latin alphabet or numbers.
The belonging of stars to the same constellation is their “visible” proximity. In fact, the stars of the same constellation are at very different distances from us.
To determine navigation elements in aircraft navigation, a relatively small number of celestial bodies are used: during the day - the Sun and sometimes the Moon; at night - the Moon, the brightest planets (Mars, Jupiter, Saturn, Venus) and the so-called aeronautical stars, for which special astronomical tables have been compiled: these are Sirius, Canopus, Vega, Arcturus, Capella, Rigel, Procyon, Achernar, Betelgeuse, Altair, Aldebaran, Antares, Pollux, Spica, Deneb, Regulus, Fomalhaut, ? Cross, ? Southern Triangle, Rigil, Aliot, Kaus Astralia, Peacock, Polar Star, Alferaz, Hamal and El Suhail.
There are several ways to find stars. One of them is as follows.
In the northern hemisphere, the starry sky is conventionally divided into three large areas with bright constellations and stars.
In the first of them (Fig. 15), the starting point for finding many aeronautical stars is the constellation Ursa Major, the seven brightest stars of which form a characteristic shape of a ladle or pan. According to ancient legend, the Big Dipper (Fig. 16) is Callisto, the daughter of King Lycaon, transformed by the goddess Hera into the bear, the daughter of King Lycaon, who was almost hunted by the dogs of the shepherd Bootes. The constellations Ursa Major, Bootes and Canes Venatici are located close to each other. The ancient Arabs called the constellation Ursa Major the Seven Brothers.
Due to the rotation of the starry sky, the handle of the bucket of the constellation Ursa Major is at different times directed to the left, now down, now up, and sometimes the bucket seems to be overturned and is visible almost above your head (Fig. 13).
The third star from the end of the bucket handle is Aliot - an aeronautical star. Its actual brightness is 3500 times greater than the brightness of our Sun. It seems like a small luminous point, because it is located at an enormous distance from us - 50 light years, although it is the closest of the stars of Ursa Major.
The second star from the end of the handle of the ladle is called Mizar. If you look closely at the space surrounding it, then on a moonless night and with good transparency of the atmosphere you can see a barely noticeable star next to it. called Alcor. This star is 6th magnitude; since its brightness is at the very limit of visibility with the naked eye, you can use it to test your vision.
If you mentally draw a straight line through the two outermost stars in the “front wall of the bucket,” then on this line at a distance equal to approximately five distances between the same stars, up from the bottom of the bucket, you can see the North Star. She is almost at the point north pole world (less than 1° from it) and therefore can serve as a reliable guide for determining the direction to the north. No wonder the peoples Central Asia They called the North Star “Temir-kozukh”, which means “iron nail”. It is 6 times further from us than Alioth. Polaris is part of the constellation Ursa Minor, the bright stars of which, although fainter than the stars of Ursa Major, resemble a ladle, but smaller.
If you draw an arc through the stars that form the handle of the Ursa Major bucket and continue it with the same radius, then on this line there will be bright stars: Arcturus, part of the constellation Bootes, and then Spica, part of the constellation Virgo.
Arcturus is 26 times larger in diameter than the Sun and is located 36.2 light years from Earth. Its actual brightness is 78 times that of the Sun.
Spica is 5 times larger in diameter than the Sun, its actual brightness is 575 times the brightness of the Sun. It is a colossal distance from us - 155 light years.
Let us continue the handle of the B. Ursa ladle along a straight line drawn through the outer and middle stars. This line will pass by the crescent-shaped constellation of the Northern Crown, clearly visible in the sky, and at a distance approximately twice as great as the distance from the Northern Corona to the middle star of the Ursa Major bucket, you can see the aeronautical star Antares, which is part of the constellation Scorpio. Corona Borealis is one of the smallest and most visible constellations in the northern sky. In the center of the constellation, the brightest star stands out - Gemma, which translated from ancient Greek means “pearl”.
Antares is one of the largest giant stars. It is 36,000,000 times larger in volume than the Sun and could include the Sun along with the Earth's orbit. Its actual brightness is 690 times greater than the brightness of the Sun. Antares is 172 light years away from us. Translated from Greek, Antares means “rival of Mars.” Like the planet Mars, Antares has a reddish color.
To find the last aeronautical star of this part of the sky - Regulus, you need to draw a straight line through two inner stars(at the base of the handle) of the B. Ursa ladle in the direction opposite to the North Star. On this line, at a distance approximately 1.5 times greater than the distance from Ursa Major to Polaris, Regulus will be located, part of the constellation Leo, the brightest stars of which form a figure somewhat reminiscent of an elongated trapezoid. The actual brightness of Regulus is 145 times greater than the brightness of the Sun, the distance to it is 83.6 light years.
Due to the apparent annual movement of the Sun, the appearance of the starry sky depends on the time of year. In spring, the firmament looks different than in summer, and in summer differently than in autumn "And in winter. The North Star and the Star Aliot, which are part of the circumpolar constellations, are visible at any time of the year. Arcturus is visible most of the year: in spring and autumn it is visible all night, in autumn it appears in the evening in the western part of the sky, then goes under the horizon, and in the morning it rises again in the eastern part of the sky. In winter, Arcturus is clearly visible in the second half of the night. Spica is a spring star; it is also clearly visible in winter after midnight.
The star Antares is clearly visible near the horizon in the spring after midnight and in the summer before midnight, when the tail of the constellation Ursa Major is lowered to the south. It is especially visible in the southern republics of the Soviet Union.
The star Regulus, like the entire constellation Leo, is one of the most beautiful and easy to find constellations, clearly visible in spring and winter.
In the second part of the sky (Fig. 17) there is one of the most beautiful constellations - Orion. Its four bright stars form a large quadrangle, inside which three more stars are located close to each other - Orion's belt. By ancient Greek myth, Orion is a giant hunter, endowed with exceptional beauty (Fig. 18).
The two brightest stars of this constellation, located in opposite corners of the quadrangle, are aeronautical stars. The star that is closer to Polaris is called Betelgeuse, and the star opposite it is called Rigel. On the continuation of the spiral line, begun in the belt and drawn through the outermost stars of the constellation Orion in a counterclockwise direction, one can successively see Aldebaran, Capella, Pollux, Procyon and Sirius.
Betelgeuse (translated from Arabic means “star in the shoulder of a giant”) is a huge luminary, a supergiant star. Its volume is many millions of times larger than the Sun; its actual brightness is 13,000 times greater than the brightness of the Sun. The surface temperature is low - about 3000°, which explains the reddish color of this star. Betelgeuse is a great distance away from us - 652 light years. Actually, now we see not the real star Betelgeuse, but the one it was like more than six centuries ago. Betelgeuse is a winter star, but is clearly visible after midnight in the fall and before midnight in early spring.
Rigel is the second most apparent bright star from the constellation Orion, which has a very (high luminosity: it is 23,000 times brighter than the Sun, its surface temperature is twice as high as the temperature of the Sun's surface. In its actual brightness, which characterizes the power of light radiation, Rigel surpasses all known stars. The source of such powerful light and thermal radiation is, like other stars, the intranuclear energy released during the transformation of some. chemical elements to others. These processes occur under the influence of enormous pressures in the interior of stars and high temperatures, reaching many millions of degrees.
The star Rigel is located 652 light years from Earth. Like the entire constellation Orion, it is visible in the winter sky, as well as in the fall after midnight.
Aldebaran is the decoration of the zodiac constellation Taurus. Ancient people imagined the figure of a wild bull in this place in the sky. In terms of brilliance, this star is inferior to Betelgeuse, but superior to Arcturus, Spica and Rigel. Aldebaran is a double star. One of its stars is 120 times brighter and 40 times larger than the Sun; the other is a small star: its brightness is only 0.002 that of the Sun. Both stars revolve around each other.
Aldebaran is visible in the sky in winter, autumn before midnight and early spring.
The constellation Taurus includes one of the many star clusters - the Pleiades. The Pleiades, according to legend, are the nine daughters of the giant Atlas, who fled from the hunter Orion who was pursuing them and were turned into stars. The Pleiades star cluster is located several hundred light years away from us. It has about 130 stars, but no more than nine can be seen with the naked eye. A person with normal vision good conditions observation can see 5-6 stars, and with more acute vision - 7-9 stars.
Capella (translated from Latin as “goat”) is the brightest star in the constellation Auriga, the brightest stars of which form a clearly visible pentagon in the sky, slightly elongated in the direction of the constellation Ursa Major. Capella is 44.6 light years away from Earth; its actual brightness is 125 times the brightness of the Sun. This is a triple star; two relatively small stars, invisible to the naked eye, revolve around it. The chapel in mid-latitudes is visible at all times of the year.
Pollux is a star in the zodiac constellation Gemini, located 32.9 light years away from us.
The Sun passes through the constellation Gemini in June (the summer solstice point is located here). In December, when the Sun is in the opposite part of the sky, the constellation Gemini is best observed at midnight. Pollux is visible in winter, almost all spring and in autumn in the second half of the night.
In the constellation Gemini, not far from Pollux (which, obviously, determined the name of the constellation), another bright star is clearly visible - Castor (Castor and Pollux are the names of the Siamese twins).
Procyon is the brightest star in the constellation Canis Minor. It is one of the medium-sized stars, its surface temperature is about 7000°, its brightness is 5.9 times greater than the brightness of the Sun. This is the closest aeronautical star to us after Rigil (? Centauri) and Sirius (11.3 light years).
Procyon is the star of the winter sky; it is also visible in early spring before midnight and in the second half of autumn after midnight.
Sirius (translated from Greek as “flaming”, “sparkling”) is the brightest star in the firmament and one of the stars closest to Earth. It is located 8.7 light years from us.
Our eye perceives only a narrow beam of visible rays. Of all electromagnetic waves, but if it had the ability to sense thermal radiation, then the brightest stars would be Antares, Aldebaran and Betelgeuse, whose maximum radiation lies in the invisible, infrared region. The star Sirius would then be in fourth place in brightness.
Sirius is 17 times brighter than the Sun; The diameter of Sirius is 1.6 times the diameter of the Sun. The surface temperature of Sirius reaches 10,000°.
When observing through binoculars, a faint white star can be detected near Sirius. This is a satellite of Sirius, orbiting around it with a period of 40 years.
Sirius is visible in autumn and early winter after midnight, and in late winter and early spring before midnight. IN ancient Rome The first morning appearance of Sirius in the rays of the rising Sun after the period of invisibility coincided with the onset of heat, the time of tropical fevers and other epidemics. At this time, a break in the work of all institutions was announced - the vacation period began. The constellation Canis Major, which includes Sirius, is called Canis Major in Latin, which means summer break from studies, or vacation. Schoolchildren and students, using the word “vacation”, obviously do not even suspect that it is connected with the name of the constellation Canis Major.
In the third section of the sky (Fig. 19), the W-shaped constellation Cassiopeia formed by five stars and the brilliant star Vega, the only bright star of the Lyra constellation, are clearly visible. The constellation Cassiopeia has no aeronautical stars, but it can serve as an excellent landmark. This bright, beautiful circumpolar constellation is located in a section of the Milky Way and therefore sparkles as if in a foyer of light, silvery fog. The most powerful known cosmic radio emission comes to us from the constellation Cassiopeia, the source of which is a barely visible ring nebula, formed more than one and a half thousand years ago as a result of the explosion of a “supernova” star. Such flares in space are not isolated and represent an extremely interesting and dynamic physical process. Due to the rapid release of nuclear energy from the depths of the star, the star suddenly begins to expand with an age of several thousand kilometers per second. The size of the star increases many thousands of times, its actual brightness reaches the brightness of millions of Suns. After some time, the star dims and becomes invisible to the naked eye, although its gas shell continues to expand for many thousands of years, emitting radio signals into space, indicating a catastrophe that has occurred in space.
On a straight line running through the two stars of Cassiopeia, the most distant from the North Star, is the star Vega; it can also be found on the continuation of a straight line drawn through the two internal stars at the base of the handle of the dipper of Ursa Major in the direction opposite to Regulus. Near Vega, four faint stars of the constellation Lyra form the characteristic figure of a small parallelogram. Vega is close in size to the Sun, its surface temperature is about 10,000°, and it is located at a distance of 26.5 light years from us.
Due to precession earth's axis The celestial pole moves among the stars and describes a counterclockwise circle in 26,000 years. By about the 22nd century, the distance from the North Star to the celestial pole will be halved and will be 28’, and after 12,000 years the celestial pole will be located near the star Vega at a distance of 6°. Vega will become like a “polar” star.
Adjacent to the constellation Lyra is the cruciform figure of the constellation Cygnus (Fig. 20). At the top of the cross is the star Deneb, which, together with Vega and Altair - the brightest star in the constellation Aquila, which resembles the figure of an airplane - forms an almost isosceles triangle.
The constellation Cygnus is located in the Milky Way region and is therefore very rich in stars. The brightest star in the constellation is Deneb, a giant among stars. Its actual brightness is 9400 times the brightness of the Sun, and its diameter is 35 times that of the Sun. The surface temperature reaches 11,000°. Deneb is located 652 light years away from us. In mid-latitudes Deneb can be observed all year round.
Altair is 8.3 times brighter than the Sun and more than twice its diameter. Altair's surface temperature is 10,000°; The distance to Earth is 16.6 light years. Altair is a star in the summer sky; it is also visible in the fall until midnight, in the first half of winter immediately after dark and in the second half of winter before dawn, in the spring in the second half of the night.
Not far from the considered constellations, on the side opposite Ursa Major from the North Star, there is a group of stars of the constellations Pegasus and Andromeda, forming the shape of a bucket, which is much larger than Ursa Major. The brightest star at the base of the handle of this bucket is ? Andromeda (? Pegasus), or Alpheratz, is an aeronautical star.
The actual brightness of Alferaz is 130 times greater than the brightness of the Sun, but it appears to us as a luminous point, since the distance to it is 120 light years. Alferats is visible in summer, autumn and in the first half of the night in winter. In spring it is visible before dawn, and for some time after dark (in March).
Not far from Alferaz towards the constellation Cassiopeia there is a small, faintly flickering cloud. With good transparency of the atmosphere, it is easy to find with the naked eye. This is the famous spiral nebula of Andromeda - our closest extragalactic neighbor (Fig. 2).
According to ancient legend, Andromeda, the daughter of the Ethiopian king Cepheus and his wife Cassiopeia, was chained to a rock on the seashore and was to be torn to pieces by the terrible Whale. The hero Perseus, passing by on the winged horse Pegasus, decided to save Andromeda. In his bag was the head of a terrible monster - Medusa, who turned everyone who looked at her into stone. Perseus, looking into his shield shining like a mirror, defeated Medusa, cutting off her head. He showed the severed head of Medusa to Keith and thereby turned him to stone. Perseus returned the rescued Andromeda to her parents. The constellations Cassiopeia, Cepheus, Pegasus, Perseus and Cetus are located in the sky around the constellation Andromeda.
On the continuation of the straight line coming from the Ursa Major bucket through the North Star and the constellation Pegasus, there is a beautiful white star Fomalhaut (mouth of the fish), which is part of the constellation Southern Pisces. Most of this southern constellation is not visible at northern latitudes, as it lies below the horizon. In August, September, October, Fomalhaut is clearly visible near the horizon. Fomalhaut is 11 times brighter than the Sun and is 23 light years away.
Between the stars Alferaz and Aldebaran there is another small aeronautical star in this part of the sky - Hamal, which is part of the constellation Aries. It is located at the apex of a right triangle formed by the star Alferaz and one of the bright stars of the constellation Cassiopeia. The handle of the bucket of the constellations Pegasus and Andromeda passes between the constellations Cassiopeia and Aries. Hamal is an autumn star, in October-November it is visible all night, in winter - in the first half of the night, in summer - in the second half.
The south pole of the world, unlike the north, is not marked by bright stars. But, like the northern, southern starry sky is very beautiful with its unique constellations and bright stars. Some of them are also used as air navigation services. These are Canopus, Achernar, Rigil, Peacock, El Suheil, Kaus Australia, ? Cross and? Southern Triangle.
The large beautiful constellation formerly known as Argo (ship of the Argonauts) is now divided into separate constellations: Carina, Puppis, Compass and Velas. It really resembles an old sailing ship with a very bright star Canopus in its keel and with the star El Suheil on the sails.
Together with Sirius and Fomalhaut, Peacock, Rigil, ? Cross and El Suheil are located on the same arc-shaped line going around the south pole of the world. Near this line, between the stars Peacock and Rigil, there is a small constellation of the Southern Triangle with the brightest star a S. Triangulum, and approximately halfway between Fomalhaut and Canopus you can see Achernar.
The aeronautical star Cous Australia, together with the stars Peacock and Antares, forms a characteristic isosceles triangle.
The star Canopus is 181 light years away from us, its brightness is 5400 times greater than the brightness of the Sun.
Rigil (? Centauri) is the closest star to us (4.24 light years). Its surface temperature reaches 5000°, and its brightness is approximately equal to the brightness of the Sun.
The star Achernar is approximately 96 light-years from Earth, has a surface temperature exceeding 16,000°, and is 370 times brighter than the Sun.
Aeronautical stars of the southern sky (Fig. 21) at high latitudes are non-setting luminaries. Therefore, they are visible all year round throughout the night. At middle and low latitudes (approximately from 0° to 60° south latitude), their visibility in the sky is determined by the time of year. Canopus is visible throughout the night in winter, in the first half of the night in spring, and in the second half in autumn. Rigil is visible throughout the night in spring, in the first half of the night in summer, and in the second half in winter. Achernar is visible all night in the fall, in the winter - in the first half of the night and in the summer - in the second half, ? The Cross is visible all night at the end of winter and early spring, in the summer - in the first half of the night, in the fall and at the beginning of winter - in the second, and the South Triangle is visible all night in the spring, in the summer - in the first half of the night, in the winter - in the second. Peacock is visible all night in summer, in autumn - in the first half of the night and in spring - in the second half. El Suheil is visible throughout the night in winter, in the first half of the night in spring, and in the second half in autumn. Cous Australia is visible all night in summer, in autumn - in the first half of the night and in spring - in the second half.
We looked at the main stars used for navigational definitions.
When studying the stars, you need to train yourself so that you can quickly find the necessary constellations and stars in certain areas of the starry sky, even in cases where other areas are covered by clouds. Usually, several careful trainings give good results, and, as a rule, practically mastered techniques for finding stars remain in memory for a lifetime.
In table 1, the purpose of which is to make it easier to find aeronautical stars in the sky, the stars are given in order of decreasing brightness. Next to the name of each of them, in parentheses it is indicated which constellation it belongs to and which letter of the Greek alphabet it is designated by.
Table 1
: Sirius (? B. Dog)
Magnitude : -1,3
Star color : White
Search method: By brightness and location relative to the constellation Orion. Located on a spiral line extending from the constellation Orion; the last, lowest star on this spiral. It is also on the straight line going through Orion's belt (Fig. 17)
Name of aeronautical star : Canopus (? Carinae)
Magnitude : -0,9
Star color : Yellow
Search method: By brightness. Located at the top of the right angle of a right triangle formed by the stars Sirius, Canopus, El Suheil (Fig. 21)
Vega (? Lyra)
Magnitude: 0,1
Star color: White
Search method: By brightness. It is located in the continuation of a line drawn through the two inner stars of the Ursa Major bucket or from the two outermost stars of Cassiopeia, the most distant from the North Star. Lines passing through Begu, Polaris and Alioth form a right angle. Near Bega there is a small parallelogram of four dim stars. Nearby is the constellation Cygnus, which has a characteristic cross shape (Fig. 19)
Name of aeronautical star: Chapel (? Charioteer)
Magnitude: 0,2
Star color: Yellow
Search method: By brightness. It is located on a spiral line coming from the constellation Orion, between this constellation and the North Star, as well as on a straight line coming from the bucket of the constellation Ursa Major (Fig. 17)
Name of aeronautical star: Arcturus (? Bootes)
Magnitude: 0,2
Star color: Orange
Search method: By brightness. Lies on the continuation of the arcuate line of the handle of the bucket of the constellation Ursa Major (Fig. 15)
Name of aeronautical star: Rigel (? Orion)
Magnitude: 0,3
Star color: Blue
Search method: Located in the lower right corner of the Orion constellation (Fig. 17)
Name of aeronautical star: Procyon (? M. Canis)
Magnitude: 0,5
Star color: White
Search method: Located on a spiral line running from the constellation Orion to the star Sirius (Fig. 17)
Name of aeronautical star: Achernar (? Eridani)
Magnitude: 0,6
Star color: Yellow
Search method: It is located approximately in the middle of the straight line connecting the stars Kapopus and Fomalhaut (Fig. 21)
Name of aeronautical star: Altair (? Orla)
Magnitude: 0,9
Star color: White
Search method: According to the characteristic constellation Aquila, whose four stars resemble the figure of an airplane. Nearby is the cross-shaped figure of the constellation Cygnus and the bright star Vega (Fig. 19)
Name of aeronautical star: Betelgeuse (? Orionis)
Magnitude: 0,9
Star color: Red
Search method: By color. Located in the upper left corner of the constellation Orion, the brightest of its two upper stars (Fig. 17)
Name of aeronautical star: Aldebaran (? Taurus)
Magnitude: 1,1
Star color: Reddish
Search method: By color. It is located on a spiral line extending from the constellation Orion. Nearby is a characteristic group of dim stars of the Pleiades (Fig. 17)
Name of aeronautical star: Pollux (? Gemini)
Magnitude: 1,2
Star color: Yellow
Search method: It is located on a spiral-shaped line coming from the constellation Orion, as well as on a straight line going through the bucket of the constellation Ursa Major (Fig. 17)
Name of aeronautical star: Spica (?Virgo)
Magnitude: 1,2
Star color: White
Search method: Located on the continuation of the arc of the handle of the bucket of the constellation Ursa Major, the next bright star behind Arcturus (Fig. 15)
Name of aeronautical star: Antares (? Scorpio)
Magnitude: 1,2
Star color: Red
Search method: It is located on the continuation of a straight line coming from the handle of the bucket of the constellation Ursa Major, near the constellation Northern Crown (Fig. 15)
Name of aeronautical star: Fomalhaut (? Southern Fish)
Magnitude: 1,3
Star color: White
Search method: It is located on the continuation of the straight line coming from the constellation Ursa Major through the North Star and the outer two stars of the bucket of the constellations Pegasus and Andromeda (Fig. 19)
Name of aeronautical star: Deneb (? Swan)
Magnitude: 1,3
Star color: White
Search method: According to the characteristic cross-shaped figure of the constellation Cygnus and the stars Vega and Altair, with which Deneb forms an almost isosceles triangle (Fig. 19)
Name of aeronautical star: Regulus (? Leo)
Magnitude: 1,3
Star color: White
Search method: It is located on the continuation of a straight line drawn through two internal stars at the base of the handle of the bucket of the constellation Ursa Major in the direction approximately opposite to the North Star (Fig. 15)
Name of aeronautical star: ? Cross
Magnitude: 1,5
Star color: Blue
Search method: According to the characteristic arrangement of the brightest stars of this constellation, forming the shape of a cross (Fig. 21)
Name of aeronautical star: Rigil (? Centauri)
Magnitude: 0,3-1,7
Star color: Yellow
Search method: It is located on an arcuate line going through the stars Fomalhaut, Pihok, Rigil, ? Cross and El Suheil, as well as at the apex of the right angle of the right triangle formed by the stars Rigil, Antares, Spiha (Fig. 21)
Name of aeronautical star: Aliot (? B. Ursa)
Magnitude: 1,7
Star color: White
Search method: The brightest star of the constellation B. Medzeditsa, the third from the end of the handle of the bucket (Fig. 15)
Name of aeronautical star: ? Southern Triangle
Magnitude: 1,9
Star color: Red
Search method: Along the characteristic triangle of bright stars. It is located near the arcuate line passing through the stars Fomalhaut, Peacock, Rigil, ? Cross, El Suheil, between the stars Peacock and Rigil (Fig. 21)
Name of aeronautical star: Kaus Australia (? Sagittarius)
Magnitude: 2,0
Star color: White
Search method: Together with Peacock and Antares, it forms an almost isosceles obtuse triangle (Fig. 21)
Name of aeronautical star: Peacock (? Peacock)
Magnitude: 2,1
Star color: Blue
Search method: It is located on an arcuate line passing through the stars Fomalhaut, Peacock, Rigil, ? Cross, El Suheil. Together with Antares and Kaus, Australia forms an almost isosceles obtuse triangle (Fig. 21)
Name of aeronautical star: Alferats (? Andromeda)
Magnitude: 2,1
Star color: White
Search method: The middle and brightest of the stars of the bucket, formed by the constellations Pegasus and Andromeda and located on the continuation of the straight line coming from the constellation Ursa Major through the North Star (Fig. 19)
Name of aeronautical star: Polar (? M. Medveditsy)
Magnitude: 2,1
Star color: White
Search method: It is located on the continuation of the straight line drawn through the two extreme stars of the bucket of the constellation Ursa Major (Fig. 15).
Name of aeronautical star: Hamal (? Aries)
Magnitude: 2,2
Star color: Red
Search method: It is located at one of the vertices of a right triangle formed by the stars Hamal, Alferaz and one of the outermost stars of the constellation Cassiopeia (Fig. 19)
Name of aeronautical star: El Suheil (? Sails)
Magnitude: 2,2
Star color: Red
Search method: Located on the arcuate line of the stars Fomalhaut, Peacock, Rigil, (? Cross, El Suheil, Sirius, (Fig. 21)
In the process of studying the starry sky, to make it easier to find and identify stars, they use maps (atlases) of the starry sky.
In aviation astronomy, a moving star map is used, known as an on-board sky map - BKN (Fig. 22). It consists of a fixed base on which a star chart with stars up to the fourth magnitude rotates around the celestial pole, and an overlay sheet with a cutout depicting the horizon for a given latitude. The star map shows four declination circles, which correspond to right ascensions 0, 90, 180 and 270°, and the celestial equator with a right ascension scale every 10°. The two declination circles have a scale of 10°. Along the edge of the oval cutout there are marks showing the position of the points of north, south, east and west, as well as an azimuth scale every 30°.
In the arched cutout of the overlay sheet, a scale of 365 divisions is visible with digitization by days and months of the year, printed on a rotating map. Along the edge of the arcuate cutout are marked the divisions of hours and tens of minutes corresponding to night time. If, by rotating the map, you combine the division of a given day with the division of a given hour of observation according to local time, then in the oval cutout you will see a picture of the starry sky corresponding to the given moment of observation according to local civil time.
For ease of use, the BKN was published for different latitudes of the Northern Hemisphere: BKN-I - for 37° (from 30 to 44°); BKN-II - for 53° (from 46 to 60°) and BKN-III - for 69° (from 62 to 72°). They differ from each other in the size and configuration of the oval cutout, which limits the visible part of the starry sky for the selected latitude.
For lower northern latitudes and for southern latitudes, there are special sky maps.
Before using the on-board sky map, it is necessary to plot the position of the planets on the image of the visible part of the sky. As mentioned above, the position of the planets among the stars is not constant, they wander across the starry sky, and therefore it is impossible to map them in advance, along with the stars. They should be applied not only when we are going to observe them, but also every time before using BKN. After all, the appearance of a planet in a certain constellation somewhat changes its general appearance and this can make it difficult to find and identify the necessary aeronautical stars.
When orienting the map, you should hold it approximately vertically in front of you, combining the designations of the horizon points with the corresponding actual directions of the cardinal points.
Using BKN, you can not only obtain a view of the starry sky for a given moment in time (month, day and hour), but also solve the following problems.
1. Mark on the ground, before the flight, the stars by which it is most convenient to make navigational determinations in the air. To do this, the map is installed at a given moment in local time and, based on the apparent position of the stars in the BKN oval, depending on the flight course, the most convenient aeronautical stars are selected for measurements. For greater accuracy of astronomical navigation determinations based on several stars, choose those whose azimuth difference between them is close to 90°.
2. Determine the horizontal and equatorial coordinates of the luminaries. To determine the equatorial coordinates, you need to set the map at a given point in time and count: the hour angle - along the arc of the equator from the southern part of the celestial meridian to the circle of declination of the star, i.e. to the straight line passing through the celestial pole and the star; declination - along the circle of declination from the celestial equator to the luminary.
To determine the horizontal coordinates, you need to mark the zenith at the center of the oval. The position of the luminary between the horizon line (the edge of the oval cutout) and the zenith characterizes the height of the luminary. The azimuth value is reported along the edge of the oval cutout from the point of north in the eastern direction to the vertical (a straight line on the map connecting the luminary to the zenith); altitude - vertically from the horizon to the luminary.
3. Determine the moments of sunrise and sunset on a certain day. To do this, by rotating the map, the image of a given luminary is placed under the edge of the oval in the eastern part, if you need to determine the rising of the luminary, or in the western part, if you need to determine the setting of the luminary. On the arched cutout opposite the given date, you can read the moment of sunrise (sunset) of the star according to local time.
4. Determine the moments of the culmination of the luminaries. To do this, the image of the luminary is installed on the celestial meridian along the north-south line between the pole and the south point, if you need to determine the upper culmination, or between the pole and the north point, if you need to determine the lower culmination. On the arched cutout opposite the given date, you can read the moment of culmination in local time.
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The picture of the starry sky, which can be observed on a clear, cloudless night, contains about 3,000 stars - a tiny fraction of the 150 million stars in our Galaxy.
For navigation purposes, from the entire set of luminaries, use a small part of them - the brightest stars, planets, as well as the Sun and Moon.
Of 9 planets solar system those of interest are those that are visible to the naked eye: Venus, Mars, Jupiter and Saturn; they are called navigational.
A list of 160 navigation stars is given in many manuals and documents, for example: MAE, Nautical tables (MT-2000), MAL.
There are 25-30 stars that are the brightest and most convenient for determining the location of the ship, which facilitates the task of identifying them in the sky.
Navigation stars are identified primarily by the configuration of the constellations in which they are located. In northern latitudes, it is most convenient to start navigating by stars by finding in the northern half of the sky the well-known constellation Ursa Major, which resembles the outline of a bucket. Next, having connected the outer stars of the bucket calamus Ursa Major (Dubhe and Msrak) with a conditional line, you should postpone the resulting segment 5 times, at the end of this extended line you will find the Ursa Minor - the Polar Star. The North Star is located almost at the point of the north celestial pole, so the direction towards it corresponds to the direction north (N), and the height of the North Star above the horizon corresponds to the geographic latitude (cf) of the observer (Fig. 6.1).
In some cases, it is more convenient to use the Orion constellation as a reference constellation (Fig. 6.2).
IN northwestern regions In Russia at the beginning of winter, this constellation in the form of a powerful narrowed quadrangle with a characteristic oblique belt is located in the southern part of the sky. To the north of Orion are the constellations Taurus, Auriga and Gemini, to the west and southwest are the constellations Canis Minor and Big Dog. The brightest stars of these constellations are Rigel, Betelgeuse, Aldebaran, Capella, Castor, Pollux, Procyon and Sirius.
Another important sign of star identification is the apparent brightness (brilliance) of the star. The brightness of a star is estimated by its “apparent magnitude” m, given in reference books. Brightness m = 0 has very bright stars (for example, Vega and Arcturus); the brightest star Sirius has a magnitude of m= -2. Stars with magnitude m = 2 are six times fainter in brilliance than stars with m = 0. On star maps and a star globe, the brilliance of stars is shown by the size of their images.
An additional sign of identifying stars is their color. Possible following colors: blue, white, orange, yellow, red, dark yellow.
A significant aid in identifying luminaries is the use of a star globe.