How to write geographic coordinates. Geographical coordinates

Gone are the days when GPS was the exclusive prerogative of navigators. Now a GPS receiver can be in a car alarm, in a video surveillance system, in a camera and in a phone. It has also become fashionable to indicate exact coordinates on business cards and websites instead of addresses.

Many have faced the different devices the coordinates look different, and attempts to get to the desired point by coordinates due to a mismatch in their recording system are accompanied by problems. You either have to look for the right place additionally, guided by signs, or in general the case ends in failure. If we are looking for something noticeable, or we know other landmarks, the matter is easily remedied. And losing at GPS orienteering competitions due to incorrect reading of the coordinates is easy to survive.

But situations can be more serious. For example, you have completely trusted your alarm with GPS tracking of the location of the car, for example, by installing the StarLine Pobedit or Pandora DXL 3700 security system. The car was stolen, but you are calm, knowing where to find it. When it comes to the practice of searching for it, problems suddenly begin: there is no car in the supposed place. Now let's imagine a much more serious situation: a person is in trouble, the coordinates of his location are known, but it is impossible to find him.

Why might this happen? The whole point turns out to be that a simple set of numbers, although very similar to each other, in non-coincident coordinate systems can lead us to a completely different place.

About coordinate recording systems

The school geography course says that coordinates should be measured in Degrees, Minutes and Seconds. Therefore, the difference in spelling is often perceived as a whim of the interface designer. But is it? This is where the catch lies, which can lead to completely unexpected consequences.

Let's figure out how the three most common coordinate systems differ.

Usual recording format: degrees, minutes, seconds

This format is used as a preset, for example, in JJ Connect navigators. It looks like this: YYY ° MM "SS, S"

The coordinates look like this:

N 067°27"13.8"
E 034°16"59.9"

What does this mean in practice?

The maximum number of degrees that can be is 180. Therefore, for latitude, where the maximum value is 90, a three-digit number is often used anyway. All three systems converge on this issue. The leading zero is often omitted, but it's usually intuitive how many digits the degrees represent. For our country, for the northern coordinate, the numbers are always at least two - from 41 in the south to 90 degrees at the North Pole, and for the east - either two or three, from 19 for Kaliningrad region up to 170 degrees in the Barents Sea.

For all three coordinate systems, the last five digits indicate fractions of a degree. In this coordinate system, minutes follow. There are 60 of them in a degree. Minutes are followed by seconds (60 in one minute) and decimal (!) fractions of a second. The confusion is added by the different format for separating decimal parts in the American and European traditions - a comma or a period.

If you don't see the usual ‘' for minutes and " for seconds, for example, the coordinates look like this:

No. 067 27 13.8
E 034 16 59.9

Or worse than that, like this:

N 672713.8
E 0341659.9

then you can recognize this format by a dot or a comma before the last digit.

The following notation format: degrees, minutes, decimal fractions of a minute

This format is used by default, for example, Garmin navigators. It looks like this: YYY°MM.SSS"

For example:

N 067°27.230"
E 034°16.998"

As seen, appearance coordinates are almost the same. There is a difference, but if it were not for the number 9, which suggests that these cannot be seconds (there cannot be more than 60, as we remember), then one would think that this is the same recording system. But no, here are minutes and decimal fractions of a minute to the third digit.

If the usual degrees and the sign of the minute at the end of the specified coordinates are absent, this recording format can be identified by a dot or a comma before the last three digits.

However, this approach also does not always give a 100% hit guarantee. For example, the MS-PGSM "Sputnik" security complex issues coordinates in a similar recording system, but the number of decimal places in minutes is not three, but four. At the same time, the number of digits for degrees is different: for latitude 2 digits, and for longitude - three. It is easy to assume this in this case due to the fact that here the point is obviously used to separate the decimal fractions of a number. Since there cannot be more than ninety degrees in latitude, the following color numbers mean minutes.

Type of recording coordinates of the security complex MS-PGSM "Sputnik"

Finally, the third notation format: degrees, decimal fractions of a degree to the fifth decimal place

In this format, there are no minutes and seconds at all. All five characters mean exclusively decimal fractions of a degree.

N 67.45383°
E 34.28331°

In the absence of a degree sign, it can be identified by the fact that there are no periods or commas between the last five digits.

The decimal format for recording coordinates as a preset, for example, is used by Lexand navigators and StarLine security systems. This form of writing coordinates makes it easier to calculate the distance between different coordinates, since this requires the cosine of the latitude angle.

So what is this long intro for?

If you look more closely at these different-looking figures, it turns out that this is the same point in different coordinate systems!

Very often there are complaints at competitions, for example, from Mercedes-Benz pilots, or when reading some navigation sheets, that “here, we were given Garmin coordinates, and we searched for an exit for a long time, but did not find it.”

Indeed, by hammering the coordinates of the first recording system into the second and vice versa, it will be difficult to find what you are looking for, but theoretically possible. The difference between the resulting points at a latitude of 67 degrees will be about 200 - 300 meters.

For example,

N 067 27 13.8 and N 067 27.138
E 034 16 59.9 and E 034 16.599

Between 27.138 "and 27" 13.8 "the difference will be as follows: in one second of latitude at this latitude 0.03087 km, that is, almost 30 meters. Our error in latitude is 5.52 seconds, that is, 170 meters.

With longitude it is not better: at this latitude in one second of longitude there will be 0.01185 km, and the difference with the real coordinates of the place is almost 24 seconds. That is approximately 280 meters.
Instead of a point, we got a rough square of 300x200 meters. It's bad, especially when you consider that the navigator itself can give inaccurate positioning with poor satellite reception. But for many tasks, the difference is quite acceptable, so often people do not think why they did not get exactly to their destination.

If you thoughtlessly drive numbers into the last recording format, then the error will be much more serious, if not to say that it will be fatal. There are more than 11 km in one tenth of a degree of latitude! Yes, and in longitude it is not better: in one tenth of a degree of longitude at a latitude of an example of more than 4 km. And the difference between the real and imaginary coordinates of a point begins already in tenths of a degree!

What to do?

In most navigators, you can change the coordinate recording systems in the settings. If the coordinates offered to you do not look the same as what you see in the navigator, do not be too lazy to deal with the device and find how the coordinate system changes. Unfortunately, given function often well "hidden" and not always easy to find.

However, in some cases it is not possible to change the coordinate system. In this case, the coordinates of the points must be recalculated to bring them into line with each other.

Default coordinate view in Lexand SG-555 and Garmin Rino 530HCx navigators

How to convert coordinates from one notation system to another?

Initial data: degrees, minutes, seconds
YYY° MM"SS,S" in YYY° MM, MMM"	New minutes are calculated like this: SS.S "/60 + MM = MM, MMM"
YYY° MM "SS, S" in YYY,YYYYY°	Seconds and minutes are converted to decimal format: SS.S "/3600 + MM/60 = 0,YYYYY
Input data: degrees, minutes, decimal fractions of a minute
YYY° MM,MMM" in YYY° MM "SS, S"	To convert decimal minutes to seconds and decimal fraction of a second, (MM,MMM" - MM)*60 = SS,S
YYY° MM,MMM" in YYY,YYYYY°	Minutes are converted to decimal degrees: MM,MMM"/60 = 0,YYYYY
Input data: degrees and decimal degrees
YYY,YYYYY° in YYY° MM "SS, S"	whole part(0,YYYYY60) = MM (0,MMM) 60 = CC,C
YYY,YYYYY° in YYY° MM, MMM"	0,YYYYY*60 = MM,MMM

Reference: how many kilometers are in one degree?

Latitude

One degree of latitude is a constant unit. The length of the meridian is 40007.86 km. Therefore, in one degree of latitude, the number of kilometers is always the same: 40007.86 km / 360 ° \u003d 111.1329 km.

Longitude

Since we are in a polar coordinate system - all longitudes converge at the poles - the number of kilometers in one degree of longitude depends on latitude. At the equator, the distance between longitudes is maximum.

The length of the equator is slightly longer than the length of the meridian and is 40075.7 km. In one degree of longitude at the equator, there is approximately the same number of kilometers as in latitude: 40075.7 km / 360 ° \u003d 111.3213 km. In order to calculate the number of kilometers in longitude at a particular latitude, you need to multiply this number by the cosine of latitude.

Those. in one degree of longitude at the 67th parallel from the example will be (40075.7 km / 360 °) x cos 67.45383 ° = 111.3213 x 0.3834 = 42.68 km

If you move closer to the equator, for example, to the 55th parallel to Moscow, then in one degree of longitude it will already be (40075.7 km / 360 °) x cos 55 ° = 63.85 km

And in Sochi and Vladivostok on the 43rd parallel in one degree of longitude it will already be (40075.7 km / 360 °) x cos 43 ° = 81.41 km.

Measured from 0° to 90° either side of the equator. The geographical latitude of points lying in the northern hemisphere (northern latitude) is considered to be positive, the latitude of points in the southern hemisphere is negative. It is customary to speak of latitudes close to the poles as high, and about those close to the equator - as about low.

Due to the difference in the shape of the Earth from the ball, the geographical latitude of the points differs somewhat from their geocentric latitude, that is, from the angle between the direction to a given point from the center of the Earth and the plane of the equator.

Longitude

Longitude- the angle λ between the plane of the meridian passing through the given point, and the plane of the initial zero meridian, from which the longitude is counted. Longitudes from 0° to 180° east of the prime meridian are called east, to the west - west. Eastern longitudes are considered to be positive, western - negative.

Height

To fully determine the position of a point in three-dimensional space, a third coordinate is needed - height. The distance to the center of the planet is not used in geography: it is convenient only when describing very deep regions of the planet or, on the contrary, when calculating orbits in space.

Within the geographic envelope, the "height above sea level" is usually used, measured from the level of the "smoothed" surface - the geoid. Such system of three coordinates turns out to be orthogonal, which simplifies a number of calculations. Altitude above sea level is also convenient in that it is related to atmospheric pressure.

The distance from the earth's surface (up or down) is often used to describe a location, however not serves coordinate

Geographic coordinate system

The main disadvantage in practical application The GCS in navigation is the large values of the angular velocity of this system at high latitudes, increasing up to infinity at the pole. Therefore, instead of HCS, a semi-free CS in azimuth is used.

Semi-free in azimuth coordinate system

The semi-free in azimuth SC differs from the HSC in only one equation, which has the form:

Accordingly, the system has the same initial position that the HCS and their orientation also coincide with the only difference that its axes and are deviated from the corresponding axes of the HCS by an angle for which the equation is valid

The conversion between the HCS and semi-free in the azimuth of the CS is carried out according to the formula

In reality, all calculations are carried out in this system, and then, to issue output information, the coordinates are transformed into the GCS.

Recording formats for geographic coordinates

The WGS84 system is used to record geographic coordinates.

Coordinates (latitude -90° to +90°, longitude -180° to +180°) can be written:

in ° degrees as a decimal fraction (modern version)
in ° degrees and "minutes with decimals
in ° degrees, " minutes and " seconds with a decimal fraction (historical notation)

The decimal separator is always a dot. Positive signs of coordinates are represented by the (in most cases, omitted) sign "+", or by the letters: "N" - north latitude and "E" - east longitude. Negative signs of coordinates are represented either by a "-" sign or by the letters: "S" - southern latitude and "W" - western longitude. Letters can stand both in front and behind.

There are no uniform rules for recording coordinates.

By default, search engine maps show coordinates in degrees with a decimal fraction with "-" signs for negative longitude. On Google maps and Yandex maps, latitude first, then longitude (until October 2012, the reverse order was adopted on Yandex maps: first longitude, then latitude). These coordinates are visible, for example, when laying routes from arbitrary points. The search also recognizes other formats.

In navigators, by default, degrees and minutes are more often shown with a decimal fraction with a letter designation, for example, in Navitel, in iGO. You can enter coordinates in accordance with other formats. The degrees and minutes format is also recommended for maritime communications.

At the same time, the original way of writing with degrees, minutes and seconds is often used. Currently, coordinates can be written in one of many ways or duplicated in two main ways (with degrees and with degrees, minutes and seconds). As an example, the options for recording the coordinates of the sign "Zero kilometer of the roads of the Russian Federation" - 55.755831 , 37.617673 55°45′20.99″ N sh. 37°37′03.62″ E d. / 55.755831 , 37.617673 (G) (O) (I):

55.755831°, 37.617673° -- degrees
N55.755831°, E37.617673° -- degrees (+ additional letters)
55°45.35"N, 37°37.06"E -- degrees and minutes (+ additional letters)
55°45"20.9916"N, 37°37"3.6228"E -- degrees, minutes and seconds (+ additional letters)

Notes

Wikimedia Foundation. 2010 .

See what "Geographic coordinates" are in other dictionaries:

See Coordinates. Mountain Encyclopedia. Moscow: Soviet Encyclopedia. Edited by E. A. Kozlovsky. 1984 1991 ... Geological Encyclopedia

- (latitude and longitude), determine the position of a point on the earth's surface. Geographical latitude j is the angle between the plumb line at a given point and the plane of the equator, counted from 0 to 90 degrees on both sides of the equator. Geographic longitude l angle ... ... Modern Encyclopedia

Latitude and longitude determine the position of a point on the earth's surface. Geographic latitude? the angle between the plumb line at a given point and the plane of the equator, counted from 0 to 90. in both directions from the equator. Geographic longitude? angle between ... ... Big Encyclopedic Dictionary

Angular values that determine the position of a point on the surface of the Earth: latitude - the angle between the plumb line at a given point and the plane of the earth's equator, measured from 0 to 90 ° (northern latitude north of the equator and southern latitude south); longitude ... ... Marine dictionary

geographical coordinates- A generalized concept of astronomical and geodetic coordinates, when the deviations of plumb lines are not taken into account. [GOST 22268 76] Topics of geodesy Generalizing terms of coordinate systems EN geographic coordinatesgeographical coordinates DE… … Technical Translator's Handbook

geographical coordinates- Values that determine the position of a point on the earth's surface (geographic latitude and geographic longitude). → Fig. 124 ... Geography Dictionary

Geographical coordinates- (latitude and longitude), determine the position of a point on the earth's surface. Geographic latitude j is the angle between the plumb line at a given point and the plane of the equator, counted from 0 to 90 ° on both sides of the equator. Geographic longitude l angle ... ... Illustrated Encyclopedic Dictionary

Latitude and longitude, angular quantities that determine the position of a point on the globe relative to the equator and the prime meridian. The latitude of a point is the angle between the plane of the equator and the plumb line at a given point; longitude - the angle drawn by ... ... Geographic Encyclopedia

The quantities that determine the position of a point on the earth's surface: latitude φ, measured by the angle between the plumb line at a given point and the plane of the earth's equator, and longitude λ, measured by the dihedral angle between the meridian plane of a given point ... ... Great Soviet Encyclopedia

Video lesson “Geographical latitude and geographical longitude. Geographical coordinates will help you get an idea of the geographic latitude and geographic longitude. The teacher will tell you how to correctly determine the geographical coordinates.

Geographic latitude- the length of the arc in degrees from the equator to the given point.

To determine the latitude of an object, you need to find the parallel on which this object is located.

For example, the latitude of Moscow is 55 degrees and 45 minutes north latitude, it is written as follows: Moscow 55 ° 45 "N; New York latitude - 40 ° 43" N; Sydney - 33°52"S

Geographic longitude is determined by meridians. Longitude can be western (from 0 meridian west to 180 meridian) and eastern (from 0 meridian east to 180 meridian). Longitudes are measured in degrees and minutes. Geographic longitude can have values from 0 to 180 degrees.

Geographic longitude- length of the arc of the equator in degrees from the initial meridian (0 degrees) to the meridian of the given point.

The prime meridian is the Greenwich meridian (0 degrees).

Rice. 2. Definition of longitudes ()

To determine longitude, you need to find the meridian on which the given object is located.

For example, the longitude of Moscow is 37 degrees and 37 minutes of east longitude, it is written as follows: 37 ° 37 "E; the longitude of Mexico City is 99 ° 08" W.

Rice. 3. Geographic latitude and geographic longitude

To accurately determine the location of an object on the surface of the Earth, you need to know its geographic latitude and geographic longitude.

Geographical coordinates- quantities that determine the position of a point on the earth's surface using latitudes and longitudes.

For example, Moscow has the following geographic coordinates: 55°45" N and 37°37" E. The city of Beijing has the following coordinates: 39°56′ N 116°24′ E The latitude value is written first.

Sometimes you need to find an object by already given coordinates, for this you must first assume in which hemispheres this object is located.

Homework

Paragraphs 12, 13.

1. What is geographic latitude and longitude?

Bibliography

Main

1. Initial course of geography: Proc. for 6 cells. general education institutions / T.P. Gerasimova, N.P. Neklyukov. - 10th ed., stereotype. - M.: Bustard, 2010. - 176 p.

2. Geography. Grade 6: atlas. - 3rd ed., stereotype. - M.: Bustard, DIK, 2011. - 32 p.

3. Geography. Grade 6: atlas. - 4th ed., stereotype. - M.: Bustard, DIK, 2013. - 32 p.

4. Geography. 6 cells: cont. cards. - M.: DIK, Bustard, 2012. - 16 p.

Encyclopedias, dictionaries, reference books and statistical collections

1. Geography. Modern illustrated encyclopedia / A.P. Gorkin. - M.: Rosmen-Press, 2006. - 624 p.

Literature for preparing for the GIA and the Unified State Examination

1. Geography: an initial course. Tests. Proc. allowance for students 6 cells. - M.: Humanit. ed. center VLADOS, 2011. - 144 p.

2. Tests. Geography. 6-10 cells: Teaching aid/ A.A. Letyagin. - M .: LLC "Agency" KRPA "Olimp": "Astrel", "AST", 2001. - 284 p.

Materials on the Internet

1. Federal Institute of Pedagogical Measurements ().

2. Russian Geographical Society ().

Latitude - the angle φ between the local direction of the zenith and the plane of the equator, measured from 0 ° to 90 ° on both sides of the equator. GEOGRAPHICAL COORDINATES - latitude and longitude, determine the position of a point on the earth's surface. By default, search engine maps show coordinates in degrees with a decimal fraction with "-" signs for negative longitude.

Eastern longitudes are considered to be positive, western - negative. To fully determine the position of a point in three-dimensional space, a third coordinate is needed - the height. The main drawback in the practical application of G.S.K. in navigation is the large values of the angular velocity of this system at high latitudes, increasing up to infinity at the pole.

These coordinates are visible, for example, when laying routes from arbitrary points. The search also recognizes other formats. The most common way to find a point on the surface of the Earth (globe) is well known - using geographical coordinates called latitude and longitude. Parallels and meridians form a grid system of coordinates on the surface of the Earth, with which any place on Earth can be precisely defined.

We can think of the Earth as a sphere rotating on its own axis. The ends of the axis are the North and South Poles. The equator is a line of latitude with a value of 0°. This means that the Equator is the starting point for measuring other lines of latitude.

All lines of latitude are parallel to the equator and are sometimes also called parallels. The equator divides the Earth into northern and southern hemispheres. Northern latitudes have positive values and southern latitudes have negative values. In the end, it was decided that the line of zero longitude passes through the Greenwich Laboratory, located in England on the eastern outskirts of London. This line is also called the zero or Greenwich meridian.

What is longitude?

Each circle line can be divided into degrees with minutes and seconds. A degree of longitude is 1/360 of the equator. The interval between the 39th and 40th parallels is 1° of latitude. The interval between the 175th and 176th meridians is 1° of longitude. In this way, complete record geographic coordinates of the Ngauruhoe volcano: 39° 07′ S, 175° 37′ E. 39 degrees, seven minutes south latitude.

What is latitude?

A second of latitude is approximately 0.03 kilometer, or approximately 30 meters. At the equator it is about 111 kilometers, the same distance as a degree of latitude. The size of longitude gradually decreases and tends to zero as the meridians converge at the Earth's poles. Thus, at a latitude of 45°, a degree of longitude is approximately 79 kilometers. As degrees of longitude change in size, minutes and seconds of longitude also change, decreasing in size towards the poles.

Almost all globes have lines of parallels and meridians. Also, many globes have a so-called meridian arc, which serves not only to hold the sphere of the globe on a stand, but also helps to determine geographical coordinates. There is a degree scale on the meridian arc (see photo). This scale is used to determine latitude. If there is no degree scale on the meridian arc, then there is such a scale on the zero meridian (Greenwich) and on the date line (180° meridian). But longitude is determined by the equator.

If this point is above the equator, then it will be the north latitude, if below the equator - the south latitude. Then determine the longitude. To do this, you need to look at the numerical value of the point of intersection of the equator and the meridian arc. This value must be viewed on the equator scale. It combines the beauty of levitation and modern technology.

An electromagnetic globe is a wonderful gift and souvenir for you and your friends. The geographical latitude of points lying in the northern hemisphere (northern latitude) is considered to be positive, the latitude of points in the southern hemisphere is negative. It is customary to speak of latitudes close to the poles as high, and those close to the equator as low. The choice of the zero meridian is arbitrary and depends only on agreement.

Within the geographic envelope, the ‘altitude above sea level’ is usually used, measured from the level of the “smoothed” surface - the geoid. Such a system of three coordinates turns out to be orthogonal, which simplifies a number of calculations. The orientation of the axes in the geographic coordinate system (GCS) is selected by the algorithm. The orientation of the trihedron is XYZ, due to the rotation of the earth and the movement of the vehicle, it constantly shifts with angular velocities.

There are no uniform rules for recording coordinates. All GPS navigators and major mapping projects on the Internet work in this coordinate system. The generally available accuracy when working with geographic coordinates is 5 - 10 meters on the ground. Coordinates are angular quantities and are expressed in degrees. AT search line maps (as well as on the panel on the right) the geographic coordinates will appear.

A panel with the address and geographic coordinates will appear below the search bar. The current location is usually captured as a waypoint, from which coordinates can later be read.

Wherein numerical values coordinates remain available (they can be seen in the search bar of the map that opens via the link). Please note that point markers displayed on the map are tied to roads, and their position corresponds to the entered coordinates only approximately. Recording forms can be simply converted one into another (1 degree = 60 minutes, 1 minute = 60 seconds).

On google maps and Yandex maps, latitude first, then longitude (until October 2012, the reverse order was adopted on Yandex maps: first longitude, then latitude). Longitude - the angle λ between the plane of the meridian passing through the given point, and the plane of the initial zero meridian, from which the longitude is counted.

1.10. RECTANGULAR COORDINATES ON MAP

Rectangular coordinates (flat) - linear quantities: abscissa X and ordinateY ,determining the position of points on a plane (on a map) relative to two mutually perpendicular axes X andY(Fig. 14). Abscissa X and ordinateYpoints AND- distances from the origin of coordinates to the bases of perpendiculars dropped from a point AND on the corresponding axes, indicating the sign.

Rice. fourteen.Rectangular coordinates

In topography and geodesy, as well as on topographic maps, orientation is carried out along the north, counting angles in a clockwise direction, therefore, to preserve the signs of trigonometric functions, the position of the coordinate axes, adopted in mathematics, is rotated by 90 °.

Rectangular coordinates on topographic maps of the USSR applied to coordinate zones. Coordinate zones - parts of the earth's surface, limited by meridians with a longitude that is a multiple of 6 °. The first zone is limited by the meridians 0° and 6°, the second - b "and 12°, the third - 12° and 18°, etc.

The zones are counted from the Greenwich meridian from west to east. The territory of the USSR is located in 29 zones: from the 4th to the 32nd inclusive. The length of each zone from north to south is about 20,000 km. The width of the zone at the equator is about 670 km, at latitude 40°- 510 km, t latitude 50°-430 km, at latitude 60°-340 km.

All topographic maps within a given zone have common system rectangular coordinates. The origin of coordinates in each zone is the point of intersection of the middle (axial) meridian of the zone with the equator (Fig. 15), the middle meridian of the zone corresponds to

Rice. 15.The system of rectangular coordinates on topographic maps: a-one zone; b-parts of the zone

the abscissa axes, and the equator - the ordinate axes. With such an arrangement of the coordinate axes, the abscissas of points located south of the equator and the ordinates of points located west of the middle meridian will have negative values. For the convenience of using coordinates on topographic maps, a conditional account of ordinates is adopted, excluding negative values of ordinates. This is achieved by the fact that the ordinates are not counted from zero, but from the value 500 km, That is, the origin of coordinates in each zone is, as it were, moved by 500 km to the left along the axisY .In addition, to unambiguously determine the position of a point in rectangular coordinates on the globe to the coordinate valueYthe zone number is assigned to the left (one-digit or two-digit number).

The relationship between conditional coordinates and their actual values is expressed by the formulas:

X" \u003d X-, Y \u003d U- 500 000,

where x" and Y"-real values of ordinates;X , Y -conditional values of ordinates. For example, if the point has coordinates

X = 5 650 450: Y= 3 620 840,

then this means that the point is located in the third zone at a distance of 120 km 840 m from the middle meridian of the zone (620840-500000) and north of the equator at a distance of 5650 km 450 m.

Full coordinates - rectangular coordinates written (named) in full, without any abbreviations. In the example above, the full coordinates of the object are given:

X = 5 650 450; Y= 3620 840.

Abbreviated coordinates are used to accelerate target designation on a topographic map, in this case only tens and units of kilometers and meters are indicated. For example, the shortened coordinates of a given object would be:

X = 50 450; Y = 20 840.

Abbreviated coordinates cannot be used when targeting at the junction of coordinate zones and if the area of action covers a space with a length of more than 100 km by latitude or longitude.

Coordinate (kilometer) grid - a grid of squares on topographic maps, formed by horizontal and vertical lines drawn parallel to the axes of rectangular coordinates at certain intervals (Table 5). These lines are called kilometers. The coordinate grid is intended for determining the coordinates of objects and drawing objects on the map by their coordinates, for target designation, map orientation, measurement of directional angles, and for approximate determination of distances and areas.

Table 5 Coordinate grids on maps

Map scales	Sizes of the sides of the squares		area of squares, sq. km
Map scales	on the map, cm	on the ground, km	area of squares, sq. km
1:25 000		1
1:50 000
1:100 000
1:200 000

On a map with a scale of 1:500,000, the coordinate grid is not shown completely; only the exits of kilometer lines are applied on the sides of the frame (after 2 cm). If necessary, a coordinate grid can be drawn on the map using these outputs.

Kilometer lines on the maps are signed at their out-of-bounds exits and at several intersections inside the sheet (Fig. 16). The kilometer lines that are extreme on the map sheet are signed in full, the rest are abbreviated, with two digits (that is, only tens and units of kilometers are indicated). Signatures near the horizontal lines correspond to distances from the y-axis (equator) in kilometers. For example, the caption 6082 in the upper right corner shows that this line is 6082 from the equator km.

The captions of the vertical lines indicate the zone number (one or two first digits) and the distance in kilometers (always three digits) from the origin, conditionally moved west of the middle meridian by 500 km. For example, the signature 4308 in the lower left corner means: 4 - zone number, 308 - distance from the conditional origin in kilometers.

An additional coordinate (kilometer) grid can be plotted on topographic maps at a scale of 1:25,000, 1:50,000, 1:100,000, and 1:200,000 at the exits of kilometer lines in the adjacent western or eastern zone. The exits of kilometer lines in the form of dashes with the corresponding signatures are given on maps located over a distance of 2 ° to the east and west of the boundary meridians of the zone.

rice. sixteen.Coordinate (kilometer) grid on a map sheet

An additional coordinate grid is intended to convert the coordinates of one zone into the coordinate system of another, neighboring, zone.

On fig. 17 dashes on the outer side of the western frame with signatures 81.6082 and on the north side of the frame with signatures 3693, 94, 95, etc. denote the exits of kilometer lines in the coordinate system of the adjacent (third) zone. If necessary, an additional coordinate grid is drawn on the map sheet by connecting dashes of the same name on opposite sides of the frame. The newly constructed grid is a continuation of the kilometer grid of the map sheet of the adjacent zone and must completely coincide (merge) with it when gluing the map.