What is azimuth in geography. Orientation on the terrain in azimuths. Determination of azimuths to local objects

Compass and azimuth.

Surely, you have heard more than once about the true and magnetic azimuth. They are radically different from each other, and therefore you need to navigate in a particular area, given these differences. You will need this so that in the future you will not encounter the following problem - when a point on the map indicated using a compass will have completely different indicators than those obtained using the map.

What is magnetic and true azimuth in geography?

The angle located between the north direction and the one that is at a certain point is the azimuth. The northern direction is called the one that is directed directly to North Pole. However, the path pointing north on the compass, of course, is considered only the direction indicating the magnetic pole. But this is not a geographic location at all. Therefore, speaking about the true pole, we are talking about the geographical, which is directly related to the shape of our planet. Plus, it is also connected with the axis of rotation of the Earth, which passes through 2 poles.

The magnetic pole is closely related to magnetic field our Earth, which has 2 poles. This field does not coincide with the true poles of the planet, just as the fields corresponding to them do not coincide with the meridians: neither with the true nor with the magnetic ones.

Having laid this or that direction between the meridians, which will directly touch the subject of the selected area, then the angle between these meridians will turn out to be the true azimuth, as well as magnetic, respectively. The difference between these azimuths is called magnetic declination. This declination can have several names, it all depends on which direction of the world it is more inclined to.

• Leaning to the east means east declination
• Leaning to the west means western declination

The declination going to the east is indicated by a plus, but to the east by a minus.

How to determine the azimuth using a compass?

To learn how to navigate correctly in a particular area and get the necessary direction, you need to calculate the azimuth using a compass. This is done very simply:

• Take in left palm compass, lay it horizontally. With help right hand release the brake that holds the needle on the compass. Start rotating the compass so that the north tip of the needle points to "0" of the scale. Then turn the ring with the sight so that the line of sight coincides with the distant object and with the one that is clearly visible. count down right amount divisions of the magnetic azimuth to this particular element. Take a count from the “0” indicator, move as the hour hand moves until you get to the number that is opposite the sight and its pointer.

• Align the pointer of the sight with the pointer to the given object. Perform this manipulation several times: first look at the pointer of the sight, then look at the pointer of the object, do the process in reverse. Remember important point: The compass should never be held close to the face, and especially to the eyes, as the accuracy of future azimuth measurements may be impaired. Use a special compass, for example, Andrianov's compass. This way you will get more accurate results.
• If you will only move in the opposite direction from the selected object, then try to calculate the back azimuth. Direct azimuth readings are less than 180 degrees, plus 180 degrees. But, and if these indicators are greater than this mark, then 180 degrees are subtracted.
• To determine the indicated direction using the old azimuth values, it is necessary to rotate the reticle ring: the reticle pointer is aligned with the indication located on the scale, which is equal to the previously set azimuth value. After that, the arrow brake on the compass is removed, its body rotates until the northern edge of the arrow points to the “0” number. The pointer of the sight will show the required course.

How to determine the azimuth using a protractor on a topographic map?

Azimuth starts at 0 and moves clockwise to 360 degrees. That is, from the northern mark of the magnetic meridian to a given point.

If you need to move exactly according to the compass, you need to indicate the azimuth values ​​\u200b\u200bon the map. This technique is used by aircraft and sea vessels that make long-distance flights or voyages. Also, this method is used by travelers during poor visibility, for example, at night, if there is no chance at all to move along a special landmark.

For the correct definition, take:

• Travel map
• Compass
• Simple pencil with ruler
• Protractor

• Mark your own location on your map. Try to navigate by the signs that are on the map.
• Find a landmark where exactly you should go. Rectilinear movement can be carried out exclusively by air or by sea. There is truth and exceptions on land - it is a desert or a steppe. As a rule, on the ground, movement occurs along a broken line, while all natural obstacles are taken into account. Therefore, you will have to regularly correct the azimuth while moving.
• Place a ruler on the route map so that your location and final destination are on this ruler. Draw with simple pencil strip until it intersects with the nearest meridian. Attach the base of your own protractor to this strip. Draw the risk, which is located in the central part, to the place where it intersects with the drawn strip - the direction should look at the landmark. From the arc of the protractor where it intersects with that strip, take the readings. Your azimuth is ready.

How to determine the azimuth from the coordinates of two points?

Determining the coordinates located between one point and another point is very simple. Draw a meridian from the starting point. This meridian should be parallel to the east frame or the west frame on the paper. Relative to this meridian, the azimuth is calculated. Since drawing a meridian is not so easy, then first you need to determine the directional angle of the direction that you want to calculate.

To measure the directional angle of the resulting line, it is necessary to draw a strip through the first point that is parallel to the abscissa axis, and then measure the directional angle. And you can still lay a strip to the place where it intersects with the coordinate strip. Where there will be an intersection, you need to measure the directional angle.

What is the difference between azimuth and directional angle?

The directional angle is measured using a protractor, as well as using a route map. Magnetic bearing is measured using a compass and terrain. If we take the true azimuth, then it is calculated due to two main elements:

• The first is the magnetic azimuth
• The second is magnetic declination.

In what units is the azimuth value measured?

As it was written above, the azimuth is measured in degrees and can start from the indicator "0" and end with the indicator "360".

Determine: what directions of the sides of the horizon correspond to the azimuths of the southeast, northeast and northwest directions?

Southeast equals 135 degrees

Northeast equals 45 degrees

Northwest equals 315 degrees

Which side of the horizon corresponds to the azimuth of 90 and 180 degrees?

90 degrees is east azimuth

180 degrees is south azimuth

Orientation of movement on the ground in azimuths: orientation angles

To orient a line means to calculate where exactly it is directed relative to the initial direction. For example, due to the meridians or the x-axis.

• The angle, which is calculated on a special scale in the direction of the hour hand, is the azimuth
• The angle that starts the calculation from the north point to the final (given) point - magnetic azimuth
• The angle located between the northern indicator of the meridian and the extreme (final) indicator is the directional angle

Video: Azimuth. Or how to use a compass on the ground?

How to determine the azimuth?

Azimuth is an indicator that is used in geography, geodesy, cartography and other sciences. It indicates the angle at a certain point on the terrain between the north direction and any object (or object on the map). More more information you can find about this indicator in our article -.

How to determine the azimuth: methods

You can determine the azimuth both by compass (if there is no map of the area), or by using a conventional protractor (if the angle is measured for an object on the map). The azimuth angle can be from 0 to 360 degrees. The reading is made in the direction of the clock hand, and the reference point (0 °) is considered the northernmost point on the map (terrain).

In this case, it is easiest to determine the azimuth of both northern and southern, eastern and western objects: it is always 0 °, 180 °, 90 ° and 270 °, respectively. It should be noted that the azimuth 360° does not exist, since its value coincides with the azimuth 0°, therefore, it is customary to consider the direction to the north as an angle with a value of 0°. You can read more about determining the cardinal points in our article -.

Determination of the azimuth using a protractor

In addition to the protractor itself, a ruler, a pencil and a map will also come in handy for this. To measure the angle, you need to put a ruler so that the point (object, object), the azimuth of which is determined, intersects with the nearest meridian. You can draw a light line with a pencil. The angle measured between this line and the meridian (north direction) will be the desired azimuth.

Determine bearing with compass

How to determine the azimuth by compass if there is no map at hand or there is no protractor on which a graduated scale indicating degrees is applied? In this way, the true azimuth is usually measured, which may differ from the magnetic one. For example, if the azimuth of an object is 40 degrees, then it may not be worth moving taking into account this change.

A map is useful here: on it you need to find the magnetic correction closest to the desired object. She may be different meanings(eg "+2" or "-3"). When determining the azimuth of 40 degrees, the magnetic correction must be taken into account and move already in the direction with the value of this correction taken into account.

Azimuth- this is the angle formed at a given point on the ground or on the map between the direction to the north and the direction to any object. Azimuth is used when moving in, in the mountains, or in conditions of poor visibility, when it is difficult, and sometimes impossible, to compare the map with the terrain and navigate it. With the help of azimuth, the direction of movement of ships and aircraft is also determined.

Azimuths are counted from the direction of the arrow (from its northern end) along the arrow from 0 ° to 360 °, in other words, from the magnetic meridian of a given point. If the object is exactly to the north from the observer, then its azimuth is 0 °, if in the east - 90 °, in the south - 180 °, in the west - 270 °. When observing with a compass, the magnetic azimuth is measured.

To determine the azimuth, the compass is positioned so that 0 ° on the dial and the letter "C" point exactly to the north, that is, the compass is oriented to the sides. Making sure that the compass box remains stationary and the arrow does not move away from the 0 ° branch, it is necessary to rotate a special sighting device and point its front sight at the object whose azimuth must be determined. Next, you need to notice at what number on the degree circle of the compass the pointer stopped. The reading on the pointer in degrees will be equal to the azimuth of this object. If the compass does not have a sighting device, it must be replaced with a thin stick. It is placed on the compass glass so that it passes through the center of the dial and is directed at the object whose azimuth must be determined.

The figure shows the compass azimuth reading, examples of determining the azimuth for some local objects: it is 50 ° for power line poles, 135 ° for a house, 210 ° for a road intersection, and 210 ° for a detached conifer tree- 330°. When recording, the azimuth is indicated by the letter A, then degrees are written (A \u003d 330 °).

Azimuth is determined not only on the ground, but also on the map. True azimuth is defined as the angle between the direction of the geographic meridian passing through a given point and the direction of the object. Geographic and magnetic poles do not match. Therefore, there is a declination of the magnetic needle. It can be western or eastern. When working on the ground, it has to be taken into account in the same way as when working with a map. Magnetic declination on given time indicated outside the frame. Using this, you can easily convert the azimuth from magnetic to true and vice versa.

To measure azimuths on the ground, it is more convenient to use a type of compass - a compass. Its main difference from a compass is that the compass has a device for sighting, that is exact definition directions to a certain point in the area. Usually these are slots in the vertical plates of the compass. A thin hair is stretched in one of these slots.

The article reveals the main methods of how to determine the azimuth using a magnetic compass and the place of its possible application. The use of azimuth is common in satellite television.

AT modern world, saturated with gadgets and technologies, only a few can independently find the direction of interest with the help of a compass and a map. The ability to find the azimuth can be useful and help out in any business.

True (geographic) azimuth is a dihedral angle counted clockwise (from 0 to 360 degrees) from the north geographic meridian to the direction line.

Magnetic azimuth is the angle formed by the magnetic meridian and the given direction of the landmark line. The countdown is clockwise (from 0 to 360 degrees). Angle search can be done using compasses, compasses. The magnetic azimuth is not accurate, as the compass needle points to a magnetic meridian that is subject to yearly changes.

Magnetic declination is the angle of difference between the true and magnetic meridian, which was mentioned earlier. It can be positive if the compass needle deviates from the true meridian to the right, or negative if it is to the left. On maps, magnetic declination is indicated relative to the year of printing. Each subsequent year of operation, the data provided are subject to adjustment.

Naturally, the magnetic declination for each region and area of ​​\u200b\u200blocation varies.

A topographic map of an area is used for various purposes. It is a universal map, with the presence of the maximum amount of information about a particular region. Divided topographic map parallels (horizontal lines) and meridians (vertical lines). The map is useful for compass orientation. Geographic location data contains information about the terrain, soils, waters, roads, and other terrain features.

Finding values ​​and working with acquired parameters

1. Plan for determining the true azimuth (using a magnetic compass):

• The compass aligns horizontally to the ground, allowing the magnetic needle to point north;
• The desired object is determined, on which the reference point is taken;
• Without changing the position, the compass bulb is adjusted to the arrow, so that the letter N (C) is clearly opposite the magnetic indicator;
• The degree is counted according to the compass divisions, from zero to the given line of the direction of the object (clockwise);
• Result - obtained magnetic azimuth;
• The magnetic declination of the given region is added or subtracted to the found degree;
• And so, the true azimuth is found.

1. Calculation of azimuth on the map:

• The desired landmark is selected and marked on the map with a dot;
• Further, from the intended landmark, a solid line is drawn from the starting point to the marked area;
• From the starting point, a parallel straight line is projected relative to the geographic meridian;
• Having two lines drawn, the protractor finds an angle that will be equal to the true azimuth.

Calculation by coordinates is similar to the process of finding the azimuth on the map. Instead of the marked landmark on the map, the coordinates of the point are taken, and the direction is built.

1. Back azimuth.

The desired direction determined by the compass or map changes by one hundred and eighty degrees, receiving a reverse calculation.

Benefits of the acquired information:

• One way to get mirror data from the opposite direction point.
• The ability to make a precise turn and follow the return path.

Application of azimuth data in the field of satellite dishes

A correctly calculated azimuth, whether using a map or a compass, will not only tell you the way back home, but will also help with setting up a satellite dish.

The main guidance parameters will be the angular coordinates of the orientation of the antenna beam axis in elevation and, of course, azimuth. Before installing the antenna, you need to decide from which satellite the signal will be caught. The coordinates of various satellites can be found on thematic sites or in the antenna purchase store. Knowing the orbital position of the satellite, you can calculate the azimuth and elevation.

The elevation angle is a degree value in the vertical plane that characterizes the angle between the horizontal and the direction to the satellite.

The calculation of this value is carried out using a special protractor, or devices based on the work of the accelerometer. Also, if you have a modern smartphone, you can download from the Internet software performing data measurements. This will definitely help the user to adjust the antenna to the chosen angle.

The direction of the satellite dish in the vertical plane can be built thanks to the compass by calculating with the found angle and getting the true azimuth (the description of the process is described earlier). Or more exact way- calculation on the map.

The theoretical part of finding the azimuth and elevation angle can be expressed in three formulas:

Az - azimuth in degrees;

El is the angle of inclination in degrees;

Lo ES - geographic longitude of the area (northern hemisphere sign - "+", southern - "-")

Lo SAT- geographical latitude terrain ( eastern hemisphere- "+", Western - "-")

La ES - longitude of the satellite position (eastern hemisphere - "+", western - "-")

After determining the correct position of the parabolic mirror of the dish, at the installation site you need to make sure that there are no direct obstacles that interrupt the reception of information (roofs, houses, trees). For example, if the elevation angle of a satellite dish is twenty degrees, obstacles are fifty degrees, we can conclude that such placement is unsuitable, since the reception lines are blocked and the signal from the satellite will not pass. It is logical that during installation it is necessary to choose the right side of the house where the plate will be placed, because the “view” sector of the parabolic mirror mounted on the wall does not exceed one hundred and eighty degrees. And it is important that the azimuth and elevation of the satellite are included in this zone.

A common option for placing a satellite dish on the roof of a building. This is a good choice terrain, as there is good review dishes. The minus is the great windiness and the impossibility of quick adjustment of the antenna, in contrast to the wall dishes adjacent to the balconies.

By correctly installing the antenna and providing good guidance to the satellite, you can achieve high-definition broadcasting of your favorite TV channels.

When determining the azimuth, it is worth:

1. You can only rely on high-quality and serviceable compasses, cheap Chinese counterparts can give an error of up to twenty degrees.
2. Have a compass of two types:

• "Finger" magnetic compass.

Pros: ease of orientation in the area, resistance to shaking. Cons: not convenient when working on the map.

• Tablet magnetic compass.

Pros: accurate calculation of the direction on the map (due to the built-in ruler), the presence of a magnifying glass.

Cons: inconvenience of use on the ground.

1. The article discusses antennas with azimuth-elevation suspension (receiving reception from one satellite) and their possible do-it-yourself localization. To adjust the polar suspension, it is necessary to invite classified specialists. Do not undertake the installation without prior experience.
2. Do not overtighten the bolts when installing the antenna mirror to suspension system. Distorting the shape of the parabolic mirror will disrupt the transmission signal, and calculating with a map with a compass will not be as effective.
3. Satellites located on the same line near the dish being installed have a ready-made attitude. Having a compass, countable programs on a smartphone and special tools you can measure the angle of inclination and azimuth of the dish (according to the converter holder bar) by copying it to your sample.
4. The SAT Finder signal meter can achieve the maximum effect of the location of the satellite dish. It determines the most advantageous rotation of the antenna to millimeter accuracy.

Azimuth- horizontal angle measured clockwise from the north direction of the meridian to the direction of the landmark or to the direction of movement. The azimuth is measured in degrees from 0º to 360º.

Movement in azimuth provides for the ability to maintain the direction of movement with the help of a compass and exit to the intended point.

The azimuth is determined on the map or on the ground after choosing the direction of movement or landmark. If the route consists of several segments of different directions, the azimuth is determined for each segment.

Azimuth can be true or magnetic, depending on whether it is measured from the true or magnetic meridian.

The directions of the true and magnetic meridians do not coincide, since the magnetic and geographic poles are at different points. The angle between these meridians is called magnetic declination.

Fig.2 Magnetic declination and azimuth

On a compass, magnetic declination looks like a deviation of the magnetic needle by a certain angle from the true meridian to the left (western magnetic declination - considered negative) or to the right (east magnetic declination - considered positive).

If we, turning the compass, match the arrow with the north direction and measure the azimuth, it will be magnetic.

To determine the true azimuth, it is necessary from the obtained value take away magnetic declination value, if it is western , or add if it is east. The magnetic declination is indicated on the map. If it is not on the map, it is determined from the reference book.

Azimuth. Personal experience.

On practice, when moving along the azimuth, referring to the compass, it is easier to set it (the compass) so that the arrow indicates the magnetic declination. Then the angle between the north direction and the direction of movement will indicate the true azimuth (see Fig. 2). In this case, there is no need to calculate and indicate the correction for the magnetic azimuth when laying a route for movement in azimuth on the map, since it will be taken into account each time the compass is accessed.

movement in azimuth.

Movement in azimuth has its own limit of accuracy. When measuring on a map and using a compass, inevitable errors occur that affect the accuracy of the direction of movement and, ultimately, the accuracy of reaching the destination and the accuracy of determining the azimuth value.

There are two ways to mitigate the effects of these errors.

First way involves minimizing error. This is achieved in several ways:

1. The method of movement in azimuth along intermediate landmarks. It consists in the fact that the entire transition is divided into segments according to clearly visible landmarks and the azimuth is calculated for each segment. In this way we will move from one to another clearly visible landmark.

2. The method of movement along the alignments, when the direction is checked by milestones left on the way (sticking branches), heaps of snow, a chain of tracks or a ski track. Looking back, we check the straightness of the movement, correct deviations. One variant of this method is to observe the people in front and correct the direction of their movement. It is easier to notice the deviation of the one ahead than one's own.

3. Bypass small obstacles alternately on the right and left. In this case, the errors in the direction are mutually leveled.

4. Method for controlling the distance traveled in time when moving in azimuth or in pairs of steps ( average length the step of a person is 0.7 m., the length of your step can be specified). In this case, there is less risk of missing the destination.

5. Obstacle avoidance method with restoration of the previous direction. If we need to get around, say, a lake, we start moving to the right or left along a new azimuth, noticing the distance traveled. Then, moving in the main direction, we go around the lake, and on the opposite bank we return along the reverse azimuth to the observed bypass distance. Then we continue the main direction of movement.

6. The method of preparing the scheme of movement in azimuth and compiling a table. Work is carried out before the exit to the route. First, a diagram is drawn up, azimuths are determined, distances are measured and entered in the table.

This is the first way to move in azimuth. It is good for small routes, as well as for training purposes.

movement in azimuth. Personal experience.

More practical in practice and more convenient to use the second way of movement in azimuth . It is characterized by ease of movement and orientation.

In this case, the azimuth is not perceived as a mandatory line of motion, but as a general direction.

For example, we need to move to the northeast. Azimuth 45º. We are moving to the northeast, imagining where the north is, where the east is. At the same time, for the convenience of moving, we can deviate to the side, subsequently making an amendment to take into account this deviation.

And if we need to go to the hut on the river bank, then it is not necessary to break through the bushes and ravines according to the calculated azimuth. It is more convenient to go along the road of a passing direction to the river upstream or downstream, and then go along the shore to the hut.

Or the case of moving in azimuth, a little more complicated, when there is a group camp on the shore of the lake that we need to get to. In the direction towards it, the area is swampy. Therefore, it is more expedient and more convenient for passing and orientation to go, say, to the bank of the river, along it to go to the mouth of a noticeable stream, from where it is more convenient to get to the lake. At the same time, you can check the direction using the compass and the map. Normal heroes, as you know, always go around.

With this method of movement in azimuth, it is advisable to control the distance traveled by the time of movement and compare the area with the map.

Having studied the map, we will know that after 10 kilometers to the right of the route, a lake should appear two kilometers to the right, and a noticeable bend of the river with an island on the left. This means that at the next bend we need to turn right and reach the height, etc.

When moving in azimuth, it is more convenient to use linear landmarks that are easier to notice - a river, a road, ridges, valleys.

This method makes it possible to choose convenient landmarks and ways to avoid obstacles. It is simple, convenient and practical.