For determining latitude it is necessary, using a triangle, to lower the perpendicular from point A to the degree frame to the line of latitude and read to the right or left on the latitude scale, the corresponding degrees, minutes, seconds. φА= φ0+ Δφ

φА=54 0 36 / 00 // +0 0 01 / 40 //= 54 0 37 / 40 //

For determining longitude it is necessary, using a triangle, to lower the perpendicular from point A to the degree frame of the line of longitude and read the corresponding degrees, minutes, seconds from above or below.

Determination of rectangular coordinates of a point on the map

The rectangular coordinates of the point (X, Y) on the map are determined in the square of the kilometer grid as follows:

1. Using a triangle, perpendiculars are lowered from point A to the kilometer grid line X and Y, values ​​are taken XA=X0+Δ X; UA=U0+Δ At

For example, the coordinates of point A are: XA \u003d 6065 km + 0.55 km \u003d 6065.55 km;

UA \u003d 4311 km + 0.535 km \u003d 4311.535 km. (coordinate is reduced);

Point A is located in the 4th zone, as indicated by the first digit of the coordinate at given.

9. Measurement of line lengths, directional angles and azimuths on the map, determination of the angle of inclination of the line specified on the map.

Length measurement

To determine the distance between points of the terrain (objects, objects) on the map, using a numerical scale, it is necessary to measure the distance between these points in centimeters on the map and multiply the resulting number by the scale value.

A small distance is easier to determine using a linear scale. To do this, it is enough to apply a compass-meter, the solution of which is equal to the distance between given points on the map, to a linear scale and take a reading in meters or kilometers.

To measure the curves, the “step” solution of the measuring compass is set so that it corresponds to an integer number of kilometers, and an integer number of “steps” is set aside on the segment measured on the map. The distance that does not fit into an integer number of “steps” of the measuring compass is determined using a linear scale and added to the resulting number of kilometers.

Measurement of directional angles and azimuths on the map

.

We connect point 1 and 2. We measure the angle. The measurement takes place with the help of a protractor, it is located parallel to the median, then the angle of inclination is reported clockwise.

Determining the slope angle of a line defined on the map.

The definition occurs exactly according to the same principle as finding the directional angle.

10. Direct and inverse geodesic problem on the plane. In the computational processing of measurements made on the ground, as well as in the design of engineering structures and calculations for transferring projects to nature, it becomes necessary to solve direct and inverse geodetic problems. Direct geodetic problem . Known coordinates X 1 and at 1 point 1, directional angle 1-2 and distance d 1-2 to point 2 you need to calculate its coordinates X 2 ,at 2 .

Rice. 3.5. To the solution of direct and inverse geodetic problems

The coordinates of point 2 are calculated by the formulas (Fig. 3.5): (3.4) where X,atincrements of coordinates equal to

(3.5)

Inverse geodesic problem . Known coordinates X 1 ,at 1 point 1 and X 2 ,at 2 points 2 need to calculate the distance between them d 1-2 and directional angle  1-2 . From formulas (3.5) and fig. 3.5 shows that. (3.6) To determine the directional angle  1-2, we use the function of the arc tangent. At the same time, we take into account that computer programs and microcalculators give the main value of the arc tangent  = , lying in the range 90+90, while the desired directional angle  can have any value in the range 0360.

The formula for the transition from  to  depends on the coordinate quarter in which the given direction is located or, in other words, on the signs of the differences y=y 2 y 1 and  x=X 2 X 1 (see table 3.1 and fig. 3.6). Table 3.1

Rice. 3.6. Directional angles and main values ​​of the arc tangent in I, II, III and IV quarters

The distance between points is calculated by the formula

(3.6) or in another way - according to the formulas (3.7)

In particular, electronic tacheometers are equipped with programs for solving direct and inverse geodetic problems, which makes it possible to determine the coordinates of observed points directly in the course of field measurements, calculate angles and distances for marking work.

And to find the exact location of objects on the earth's surface allows degree network- a system of parallels and meridians. It serves to determine the geographical coordinates of points on the earth's surface - their longitude and latitude.

Parallels(from Greek. parallelos- walking nearby) - these are lines conditionally drawn on the earth's surface parallel to the equator; equator - a line of section of the earth's surface depicted by a plane passing through the center of the earth perpendicular to the axis of its rotation. The longest parallel is the equator; the length of the parallels from the equator to the poles decreases.

meridians(from lat. meridianus- midday) - lines conventionally drawn on the earth's surface from one pole to another along the shortest path. All meridians are equal in length. All points of a given meridian have the same longitude, and all points of a given parallel have the same latitude.

Rice. 1. Elements of a degree network

Geographic latitude and longitude

Geographic latitude of the point is the value of the meridian arc in degrees from the equator to the given point. It varies from 0° (equator) to 90° (pole). Distinguish between northern and southern latitudes, abbreviated n. and y.sh. (Fig. 2).

Any point south of the equator will have a south latitude, and any point north of the equator will have a north latitude. To determine the geographical latitude of any point means to determine the latitude of the parallel on which it is located. On maps, the latitude of parallels is signed on the right and left frames.

Rice. 2. Latitude

Geographic longitude of a point is the magnitude of the parallel arc in degrees from the prime meridian to the given point. The initial (zero, or Greenwich) meridian passes through the Greenwich Observatory, located near London. To the east of this meridian, the longitude of all points is east; to the west, it is west (Fig. 3). Longitude varies from 0 to 180°.

Rice. 3. Geographic longitude

To determine the geographical longitude of any point means to determine the longitude of the meridian on which it is located.

On the maps, the longitude of the meridians is signed on the upper and lower frames, and on the map of the hemispheres - on the equator.

The latitude and longitude of any point on Earth make up its geographical coordinates. Thus, the geographic coordinates of Moscow are 56°N. and 38°E

Geographic coordinates of cities in Russia and CIS countries

City	Latitude	Longitude
Abakan	53.720976	91.44242300000001
Arkhangelsk	64.539304	40.518735
Astana(Kazakhstan)	71.430564	51.128422
Astrakhan	46.347869	48.033574
Barnaul	53.356132	83.74961999999999
Belgorod	50.597467	36.588849
Biysk	52.541444	85.219686
Bishkek (Kyrgyzstan)	42.871027	74.59452
Blagoveshchensk	50.290658	127.527173
Bratsk	56.151382	101.634152
Bryansk	53.2434	34.364198
Velikiy Novgorod	58.521475	31.275475
Vladivostok	43.134019	131.928379
Vladikavkaz	43.024122	44.690476
Vladimir	56.129042	40.40703
Volgograd	48.707103	44.516939
Vologda	59.220492	39.891568
Voronezh	51.661535	39.200287
Grozny	43.317992	45.698197
Donetsk, Ukraine)	48.015877	37.80285
Yekaterinburg	56.838002	60.597295
Ivanovo	57.000348	40.973921
Izhevsk	56.852775	53.211463
Irkutsk	52.286387	104.28066
Kazan	55.795793	49.106585
Kaliningrad	55.916229	37.854467
Kaluga	54.507014	36.252277
Kamensk-Uralsky	56.414897	61.918905
Kemerovo	55.359594	86.08778100000001
Kyiv(Ukraine)	50.402395	30.532690
Kirov	54.079033	34.323163
Komsomolsk-on-Amur	50.54986	137.007867
Korolev	55.916229	37.854467
Kostroma	57.767683	40.926418
Krasnodar	45.023877	38.970157
Krasnoyarsk	56.008691	92.870529
Kursk	51.730361	36.192647
Lipetsk	52.61022	39.594719
Magnitogorsk	53.411677	58.984415
Makhachkala	42.984913	47.504646
Minsk, Belarus)	53.906077	27.554914
Moscow	55.755773	37.617761
Murmansk	68.96956299999999	33.07454
Naberezhnye Chelny	55.743553	52.39582
Nizhny Novgorod	56.323902	44.002267
Nizhny Tagil	57.910144	59.98132
Novokuznetsk	53.786502	87.155205
Novorossiysk	44.723489	37.76866
Novosibirsk	55.028739	82.90692799999999
Norilsk	69.349039	88.201014
Omsk	54.989342	73.368212
Eagle	52.970306	36.063514
Orenburg	51.76806	55.097449
Penza	53.194546	45.019529
Pervouralsk	56.908099	59.942935
Permian	58.004785	56.237654
Prokopyevsk	53.895355	86.744657
Pskov	57.819365	28.331786
Rostov-on-Don	47.227151	39.744972
Rybinsk	58.13853	38.573586
Ryazan	54.619886	39.744954
Samara	53.195533	50.101801
St. Petersburg	59.938806	30.314278
Saratov	51.531528	46.03582
Sevastopol	44.616649	33.52536
Severodvinsk	64.55818600000001	39.82962
Severodvinsk	64.558186	39.82962
Simferopol	44.952116	34.102411
Sochi	43.581509	39.722882
Stavropol	45.044502	41.969065
Sukhum	43.015679	41.025071
Tambov	52.721246	41.452238
Tashkent (Uzbekistan)	41.314321	69.267295
Tver	56.859611	35.911896
Tolyatti	53.511311	49.418084
Tomsk	56.495116	84.972128
Tula	54.193033	37.617752
Tyumen	57.153033	65.534328
Ulan-Ude	51.833507	107.584125
Ulyanovsk	54.317002	48.402243
Ufa	54.734768	55.957838
Khabarovsk	48.472584	135.057732
Kharkov, Ukraine)	49.993499	36.230376
Cheboksary	56.1439	47.248887
Chelyabinsk	55.159774	61.402455
Mines	47.708485	40.215958
Engels	51.498891	46.125121
Yuzhno-Sakhalinsk	46.959118	142.738068
Yakutsk	62.027833	129.704151
Yaroslavl	57.626569	39.893822

In order to find the desired object on a map, you need to know its geographical coordinates - latitude and longitude.

Remember how you found a point on the coordinate plane in math lessons? In the same way, you can find any point on the planet using the system of parallels and meridians, or, as it is also called, the degree network.

First, set the geographic latitude of the point. That is, determine how far it is from the equator. To do this, calculate the value of the meridian arc from the equator to this point in degrees. Geographic latitude can vary from 0° to 90°. All points in the Northern Hemisphere have a northern latitude (abbreviated north latitude), and in the southern hemisphere they have a southern latitude (abbreviated south latitude).

Determination of geographical coordinates

To determine the geographic latitude of any point on the globe and map, you need to find out on which parallel it is located. For example, if Moscow is located on the parallel between 50° and 60° N. latitude, then its latitude is approximately 56 ° N. sh. All points of the same parallel have the same latitude. In order to establish the geographic longitude of a point, you need to find out how far it is from the initial (zero) meridian. It is conducted through the old building of the Greenwich Observatory, built in 1675 near London. This meridian is chosen conditionally as the zero meridian. It's called Greenwich. The magnitude of the arc of the parallel from it to a given point is measured in the same way as the geographic latitude - in degrees. If you move from the zero meridian to the east, then the longitude will be east (abbreviated east), and if you move west, west (abbreviated west). The value of longitude can be from 0° to 180°. To determine the geographical longitude of any point means to establish the longitude of the meridian on which it is located. So, Moscow is located at 38 ° E. Yes

Coordinates called angular and linear quantities (numbers) that determine the position of a point on a surface or in space.

In topography, such coordinate systems are used that allow the most simple and unambiguous determination of the position of points on the earth's surface, both from the results of direct measurements on the ground and using maps. These systems include geographic, flat rectangular, polar and bipolar coordinates.

Geographical coordinates(Fig.1) - angular values: latitude (j) and longitude (L), which determine the position of the object on the earth's surface relative to the origin of coordinates - the point of intersection of the initial (Greenwich) meridian with the equator. On the map, the geographic grid is indicated by a scale on all sides of the map frame. The western and eastern sides of the frame are meridians, while the northern and southern sides are parallels. In the corners of the map sheet, the geographical coordinates of the points of intersection of the sides of the frame are signed.

Rice. 1. The system of geographical coordinates on the earth's surface

In the geographic coordinate system, the position of any point on the earth's surface relative to the origin of coordinates is determined in angular measure. For the beginning, in our country and in most other states, the point of intersection of the initial (Greenwich) meridian with the equator is accepted. Being, therefore, the same for our entire planet, the system of geographical coordinates is convenient for solving problems of determining the relative position of objects located at considerable distances from each other. Therefore, in military affairs, this system is used mainly for conducting calculations related to the use of long-range combat weapons, such as ballistic missiles, aviation, etc.

Planar rectangular coordinates(Fig. 2) - linear quantities that determine the position of the object on the plane relative to the accepted origin - the intersection of two mutually perpendicular lines (coordinate axes X and Y).

In topography, each 6-degree zone has its own system of rectangular coordinates. The X-axis is the axial meridian of the zone, the Y-axis is the equator, and the point of intersection of the axial meridian with the equator is the origin of coordinates.

Rice. 2. System of flat rectangular coordinates on maps

The system of flat rectangular coordinates is zonal; it is set for each six-degree zone into which the Earth's surface is divided when it is depicted on maps in the Gaussian projection, and is intended to indicate the position of images of points on the earth's surface on a plane (map) in this projection.

The origin of coordinates in the zone is the point of intersection of the axial meridian with the equator, relative to which the position of all other points of the zone is determined in a linear measure. The origin of the zone coordinates and its coordinate axes occupy a strictly defined position on the earth's surface. Therefore, the system of flat rectangular coordinates of each zone is connected both with the coordinate systems of all other zones, and with the system of geographical coordinates.

The use of linear quantities to determine the position of points makes the system of flat rectangular coordinates very convenient for making calculations both when working on the ground and on the map. Therefore, this system finds the widest application in the troops. Rectangular coordinates indicate the position of terrain points, their battle formations and targets, with their help they determine the relative position of objects within one coordinate zone or in adjacent sections of two zones.

Polar and bipolar coordinate systems are local systems. In military practice, they are used to determine the position of some points relative to others in relatively small areas of the terrain, for example, in target designation, marking landmarks and targets, drawing up terrain maps, etc. These systems can be associated with systems of rectangular and geographical coordinates.

2. Determination of geographical coordinates and mapping of objects by known coordinates

The geographical coordinates of a point located on the map are determined from the parallels and meridians closest to it, the latitude and longitude of which are known.

The frame of the topographic map is divided into minutes, which are separated by dots into divisions of 10 seconds each. Latitudes are indicated on the sides of the frame, and longitudes are indicated on the northern and southern sides.

Rice. 3. Determination of the geographical coordinates of a point on the map (point A) and drawing a point on the map by geographical coordinates (point B)

Using the minute frame of the map, you can:

1 . Determine the geographic coordinates of any point on the map.

For example, the coordinates of point A (Fig. 3). To do this, use a measuring compass to measure the shortest distance from point A to the southern frame of the map, then attach the meter to the western frame and determine the number of minutes and seconds in the measured segment, add the resulting (measured) value of minutes and seconds (0 "27") with the latitude of the southwestern corner of the frame - 54 ° 30 ".

Latitude points on the map will be equal to: 54°30"+0"27" = 54°30"27".

Longitude defined in a similar way.

Using a measuring compass, measure the shortest distance from point A to the western frame of the map, apply the measuring compass to the southern frame, determine the number of minutes and seconds in the measured segment (2 "35"), add the obtained (measured) value to the longitude of the southwestern corner frames - 45°00".

Longitude points on the map will be equal to: 45°00"+2"35" = 45°02"35"

2. Put any point on the map according to the given geographical coordinates.

For example, point B latitude: 54°31 "08", longitude 45°01 "41".

To map a point in longitude, it is necessary to draw a true meridian through a given point, for which connect the same number of minutes along the northern and southern frames; to plot a point in latitude on a map, it is necessary to draw a parallel through this point, for which connect the same number of minutes along the western and eastern frames. The intersection of two lines will determine the location of point B.

3. Rectangular coordinate grid on topographic maps and its digitization. Additional grid at the junction of coordinate zones

The coordinate grid on the map is a grid of squares formed by lines parallel to the coordinate axes of the zone. The grid lines are drawn through an integer number of kilometers. Therefore, the coordinate grid is also called the kilometer grid, and its lines are kilometer.

On the 1:25000 map, the lines forming the coordinate grid are drawn through 4 cm, that is, through 1 km on the ground, and on maps 1:50000-1:200000 through 2 cm (1.2 and 4 km on the ground, respectively). On the 1:500000 map, only the exits of the coordinate grid lines are plotted on the inner frame of each sheet after 2 cm (10 km on the ground). If necessary, coordinate lines can be drawn on the map along these exits.

On topographic maps, the values ​​of the abscissas and ordinates of the coordinate lines (Fig. 2) are signed at the exits of the lines behind the inner frame of the sheet and nine places on each sheet of the map. The full values ​​of abscissas and ordinates in kilometers are signed near the coordinate lines closest to the corners of the map frame and near the intersection of the coordinate lines closest to the northwestern corner. The rest of the coordinate lines are signed in abbreviated form with two digits (tens and units of kilometers). Signatures near the horizontal lines of the coordinate grid correspond to distances from the y-axis in kilometers.

Signatures near the vertical lines indicate the zone number (one or two first digits) and the distance in kilometers (always three digits) from the origin of coordinates, conditionally moved to the west of the zone's central meridian by 500 km. For example, the signature 6740 means: 6 - zone number, 740 - distance from the conditional origin in kilometers.

The outputs of the coordinate lines are given on the outer frame ( additional grid) coordinate systems of the adjacent zone.

4. Determination of rectangular coordinates of points. Drawing points on the map by their coordinates

On the coordinate grid using a compass (ruler) you can:

1. Determine the rectangular coordinates of a point on the map.

For example, points B (Fig. 2).

For this you need:

• write X - digitization of the lower kilometer line of the square in which point B is located, i.e. 6657 km;
• measure along the perpendicular the distance from the lower kilometer line of the square to point B and, using the linear scale of the map, determine the value of this segment in meters;
• add the measured value of 575 m with the digitization value of the lower kilometer line of the square: X=6657000+575=6657575 m.

The Y ordinate is determined in the same way:

• write the Y value - the digitization of the left vertical line of the square, i.e. 7363;
• measure the perpendicular distance from this line to point B, i.e. 335 m;
• add the measured distance to the Y digitization value of the left vertical line of the square: Y=7363000+335=7363335 m.

2. Put the target on the map according to the given coordinates.

For example, point G by coordinates: X=6658725 Y=7362360.

For this you need:

• find the square in which the point G is located by the value of whole kilometers, i.e. 5862;
• set aside from the lower left corner of the square a segment on the scale of the map, equal to the difference between the abscissa of the target and the lower side of the square - 725 m;
• from the obtained point along the perpendicular to the right, set aside a segment equal to the difference in the ordinates of the target and the left side of the square, i.e. 360 m.

Rice. 2. Determining the rectangular coordinates of a point on the map (point B) and plotting a point on the map using rectangular coordinates (point D)

5. Accuracy of determining coordinates on maps of various scales

The accuracy of determining geographical coordinates on maps 1:25000-1:200000 is about 2 and 10 "" respectively.

The accuracy of determining the rectangular coordinates of points on a map is limited not only by its scale, but also by the magnitude of the errors allowed when shooting or compiling a map and drawing various points and terrain objects on it

Geodetic points and are plotted most accurately (with an error not exceeding 0.2 mm) on the map. objects that stand out most sharply on the ground and are visible from afar, having the value of landmarks (individual bell towers, factory chimneys, tower-type buildings). Therefore, the coordinates of such points can be determined with approximately the same accuracy with which they are plotted on the map, i.e. for a map of a scale of 1:25000 - with an accuracy of 5-7 m, for a map of a scale of 1:50000 - with an accuracy of -10- 15 m, for a map at a scale of 1:100000 - with an accuracy of 20-30 m.

The remaining landmarks and contour points are plotted on the map, and, therefore, are determined from it with an error of up to 0.5 mm, and points related to contours that are not clearly expressed on the ground (for example, the contour of a swamp), with an error of up to 1 mm.

6. Determining the position of objects (points) in systems of polar and bipolar coordinates, mapping objects in direction and distance, in two angles or in two distances

System flat polar coordinates(Fig. 3, a) consists of a point O - the origin, or poles, and the initial direction of the OR, called polar axis.

Rice. 3. a – polar coordinates; b – bipolar coordinates

The position of the point M on the ground or on the map in this system is determined by two coordinates: the position angle θ, which is measured clockwise from the polar axis to the direction to the determined point M (from 0 to 360 °), and the distance OM = D.

Depending on the task being solved, an observation point, a firing position, a starting point for movement, etc. are taken as a pole, and a geographic (true) meridian, a magnetic meridian (the direction of a magnetic compass needle) or a direction to some landmark is taken as a polar axis .

These coordinates can be either two position angles that determine directions from points A and B to the desired point M, or distances D1=AM and D2=BM to it. The position angles, as shown in Fig. 1, b, are measured at points A and B or from the direction of the basis (i.e., angle A=BAM and angle B=ABM) or from any other directions passing through points A and B and taken as initial ones. For example, in the second case, the location of the point M is determined by the position angles θ1 and θ2, measured from the direction of the magnetic meridians. System flat bipolar (two-pole) coordinates(Fig. 3, b) consists of two poles A and B and a common axis AB, called the basis or base of the serif. The position of any point M relative to the two data on the map (terrain) points A and B is determined by the coordinates that are measured on the map or on the terrain.

Drawing the detected object on the map

This is one of the most important moments in object detection. The accuracy of determining its coordinates depends on how accurately the object (target) will be mapped.

Having found an object (target), you must first determine exactly what is detected by various signs. Then, without stopping the observation of the object and without revealing yourself, put the object on the map. There are several ways to plot an object on a map.

visually: Places a feature on the map when it is close to a known landmark.

By direction and distance: to do this, you need to orient the map, find the point of your standing on it, sight on the map the direction to the detected object and draw a line to the object from the point of your standing, then determine the distance to the object by measuring this distance on the map and commensurate it with the scale of the map.

Rice. 4. Drawing a target on the map with a straight cut from two points.

If in this way it is graphically impossible to solve the problem (the enemy interferes, poor visibility, etc.), then you need to accurately measure the azimuth to the object, then translate it into a directional angle and draw a direction on the map from the standing point, on which to plot the distance to the object.

To get the directional angle, you need to add the magnetic declination of this map (direction correction) to the magnetic azimuth.

straight serif. In this way, an object is put on a map of 2-3 points from which it is possible to observe it. To do this, from each selected point, the direction to the object is drawn on the oriented map, then the intersection of straight lines determines the location of the object.

7. Ways of targeting on the map: in graphic coordinates, flat rectangular coordinates (full and abbreviated), by squares of a kilometer grid (up to a whole square, up to 1/4, up to 1/9 of a square), from a landmark, from a conditional line, by azimuth and target range, in the bipolar coordinate system

The ability to quickly and correctly indicate targets, landmarks and other objects on the ground is important for controlling subunits and fire in combat or for organizing combat.

Target designation in geographic coordinates It is used very rarely and only in those cases when the targets are removed from a given point on the map at a considerable distance, expressed in tens or hundreds of kilometers. In this case, geographical coordinates are determined from the map, as described in question No. 2 of this lesson.

The location of the target (object) is indicated by latitude and longitude, for example, height 245.2 (40 ° 8 "40" N, 65 ° 31 "00" E). On the eastern (western), northern (southern) sides of the topographic frame, mark the position of the target in latitude and longitude with a prick of a compass. From these marks, perpendiculars are lowered into the depth of the sheet of the topographic map until they intersect (commander's rulers, standard sheets of paper are applied). The point of intersection of the perpendiculars is the position of the target on the map.

For approximate target designation rectangular coordinates it is enough to indicate on the map the square of the grid in which the object is located. The square is always indicated by the numbers of kilometer lines, the intersection of which forms the southwestern (lower left) corner. When indicating the square, the cards follow the rule: first they name two numbers signed at the horizontal line (at the western side), that is, the “X” coordinate, and then two numbers at the vertical line (south side of the sheet), that is, the “Y” coordinate. In this case, "X" and "Y" are not spoken. For example, enemy tanks are spotted. When transmitting a report by radiotelephone, the square number is pronounced: eighty-eight zero two.

If the position of a point (object) needs to be determined more accurately, then full or abbreviated coordinates are used.

Work with full coordinates. For example, it is required to determine the coordinates of a road sign in square 8803 on a map at a scale of 1:50000. First, determine what is the distance from the lower horizontal side of the square to the road sign (for example, 600 m on the ground). In the same way, measure the distance from the left vertical side of the square (for example, 500 m). Now, by digitizing kilometer lines, we determine the full coordinates of the object. The horizontal line has the signature 5988 (X), adding the distance from this line to the road sign, we get: X=5988600. In the same way, we determine the vertical line and get 2403500. The full coordinates of the road sign are as follows: X=5988600 m, Y=2403500 m.

Abbreviated coordinates respectively will be equal: X=88600 m, Y=03500 m.

If it is required to clarify the position of the target in a square, then target designation is used by letter or number inside the square of the kilometer grid.

When targeting in a literal way inside the square of the kilometer grid, the square is conditionally divided into 4 parts, each part is assigned a capital letter of the Russian alphabet.

The second way - digital way target designation inside the kilometer grid square (target designation by snail ). This method got its name from the arrangement of conditional digital squares inside the square of the kilometer grid. They are arranged as if in a spiral, while the square is divided into 9 parts.

When targeting in these cases, they name the square in which the target is located, and add a letter or number that specifies the position of the target inside the square. For example, a height of 51.8 (5863-A) or a high-voltage support (5762-2) (see Fig. 2).

Target designation from a landmark is the simplest and most common method of target designation. With this method of target designation, the nearest landmark to the target is first called, then the angle between the direction to the landmark and the direction to the target in goniometer divisions (measured with binoculars) and the distance to the target in meters. For example: "Landmark two, forty to the right, further two hundred, at a separate bush - a machine gun."

target designation from the conditional line usually used in combat vehicles. With this method, two points are selected on the map in the direction of action and connected by a straight line, relative to which target designation will be carried out. This line is indicated by letters, divided into centimeter divisions and numbered starting from zero. Such a construction is done on the maps of both the transmitting and receiving target designation.

Target designation from a conditional line is usually used in combat vehicles. With this method, two points are selected on the map in the direction of action and connected by a straight line (Fig. 5), relative to which target designation will be carried out. This line is indicated by letters, divided into centimeter divisions and numbered starting from zero.

Rice. 5. Target designation from a conditional line

Such a construction is done on the maps of both the transmitting and receiving target designation.

The position of the target relative to the conditional line is determined by two coordinates: a segment from the starting point to the base of the perpendicular, lowered from the target location point to the conditional line, and a segment of the perpendicular from the conditional line to the target.

When targeting, the conditional name of the line is called, then the number of centimeters and millimeters contained in the first segment, and, finally, the direction (left or right) and the length of the second segment. For example: “Direct AC, five, seven; zero to the right, six - NP.

Target designation from a conditional line can be issued by indicating the direction to the target at an angle from the conditional line and the distance to the target, for example: "Direct AC, right 3-40, one thousand two hundred - machine gun."

target designation in azimuth and range to the target. The azimuth of the direction to the target is determined using a compass in degrees, and the distance to it is determined using an observation device or by eye in meters. For example: "Azimuth thirty-five, range six hundred - a tank in a trench." This method is most often used in areas where there are few landmarks.

8. Problem solving

Determining the coordinates of terrain points (objects) and target designation on the map is practiced practically on training maps using pre-prepared points (marked objects).

Each student determines geographic and rectangular coordinates (maps objects at known coordinates).

Methods of target designation on the map are worked out: in flat rectangular coordinates (full and abbreviated), in squares of a kilometer grid (up to a whole square, up to 1/4, up to 1/9 of a square), from a landmark, in azimuth and range of the target.

There are many different coordinate systems. All of them are used to determine the position of points on the earth's surface. This includes mainly geographic coordinates, flat rectangular and polar coordinates. In general, it is customary to call coordinates angular and linear quantities that define points on a surface or in space.

Geographic coordinates are angular values ​​- latitude and longitude, which determine the position of a point on the globe. Geographic latitude is the angle formed by the plane of the equator and a plumb line at a given point on the earth's surface. This angle value shows how far a particular point on the globe is north or south of the equator.

If the point is located in the Northern Hemisphere, then its geographical latitude will be called northern, and if in the Southern Hemisphere - southern latitude. The latitude of points located on the equator is zero degrees, and at the poles (North and South) - 90 degrees.

Geographic longitude is also an angle, but formed by the plane of the meridian, taken as the initial (zero), and the plane of the meridian passing through the given point. For the uniformity of the definition, it was agreed to consider the meridian passing through the astronomical observatory in Greenwich (near London) as the initial meridian and call it Greenwich.

All points located to the east from it will have eastern longitude (up to the meridian of 180 degrees), and to the west of the initial one - western longitude. The figure below shows how to determine the position of point A on the earth's surface if its geographical coordinates (latitude and longitude) are known.

Note that the difference in longitudes of two points on Earth shows not only their relative position with respect to the zero meridian, but also the difference in these points at the same moment. The fact is that every 15 degrees (24th part of the circle) in longitude is equal to one hour of time. Based on this, it is possible to determine the difference in time at these two points by geographical longitude.

For example.

Moscow has a longitude of 37°37′ (East), and Khabarovsk -135°05′, that is, lies to the east of 97°28′. What time do these cities have at the same moment? Simple calculations show that if it is 13:00 in Moscow, then it is 19:30 in Khabarovsk.

The figure below shows the design of the sheet frame of any map. As can be seen from the figure, in the corners of this map, the longitude of the meridians and the latitude of the parallels that form the frame of the sheet of this map are signed.

On all sides, the frame has scales divided into minutes. For both latitude and longitude. Moreover, each minute is divided by dots into 6 equal sections, which correspond to 10 seconds of longitude or latitude.

Thus, in order to determine the latitude of any point M on the map, it is necessary to draw a line through this point parallel to the lower or upper frame of the map, and read the corresponding degrees, minutes, seconds on the latitude scale to the right or left. In our example, point M has a latitude of 45°31’30”.

Similarly, drawing a vertical line through the point M parallel to the lateral (closest to this point) meridian of the border of this sheet of the map, we read the longitude (east) equal to 43 ° 31'18 ".

Drawing a point on a topographic map according to given geographical coordinates.

Drawing a point on the map according to the given geographical coordinates is carried out in the reverse order. First, the indicated geographical coordinates are found on the scales, and then parallel and perpendicular lines are drawn through them. Intersecting them on will show the point with the given geographic coordinates.

Based on the book "The map and the compass are my friends."
Klimenko A.I.