As soon as humanity discovered that the Earth has the shape of a ball, the first question that arose was the determination of the location on the ground. It turned out to be possible to solve it thanks to the joint development of geodesy, astronomy and technology. The article discusses in detail the questions of what is latitude and longitude.

The concept of latitude

First, let's define what latitude is. In geography, it is understood as the angle formed by a straight line passing through a given point on the surface of the planet and through its center with the equatorial plane. According to this definition, the apex of the angle that determines the geographic latitude is located in the center of our planet, through which the equatorial plane also passes. If, without changing this angle, you rotate the straight line connecting the center and a point on the surface around an axis perpendicular to the equator, then the straight line will draw a circle on the surface of the Earth. As you might guess, all points of this circle will have the same latitude. This circle is called a parallel.

Knowing the definition of what latitude is, we can safely say that this value is measured in degrees. Since the maximum value of the angle between a straight line and a plane is 90o, this figure shows greatest value latitude (it corresponds to the poles of our planet). Smallest value latitudes (0o) are points that lie on the equatorial circle.

How is latitude recorded?

Since the Earth is spherical (geoid, to be precise), the equator divides it into two equal hemispheres. The upper one is called the northern one, and the lower one is called the southern one. This fact is taken into account when recording the coordinates of the geographical latitude. It should also be recalled that geographic degrees are expressed in the sexagesimal system, that is, the whole circle is 360o, 1o is 60 "(minutes), and 1" includes 60 "" (seconds). There are two ways to represent latitude coordinates:

  • Use of "+" and "-" signs, the first of which corresponds to the northern hemisphere, the second to the southern. For example, the numbers 22o45 "11" "mean 22 degrees 45 minutes and 11 seconds north.
  • Adding Latin letters N (north) or S (south). The entry 22o45 "11" "N defines the same latitude as in the example above. Russian maps may use the letters" C "and" U "for the northern and southern hemispheres, respectively.

It is curious to give the value of the distance on the surface of the planet, which corresponds to 1o of latitude. It is not constant because the Earth is flattened from the poles. So, at the latitude of the equator 1o = 110.57 km, near the poles 1o = 111.70 km. Usually, the average value of this value is used, it is 111.12 km. One minute from last value is equal to 1852 meters and is called a nautical mile. One second of latitude is on average 30 m 86 cm.

Important parallels


Due to the round shape of our planet, the sun's rays fall on it from different angles. Moreover, the magnitude of the angle of incidence is uniquely determined by the geographic latitude. Where the sun's rays fall at right angles to the surface, the earth, air and water are warmed up more. This situation is typical for low latitudes... On the contrary, small angles of incidence of rays lead to the fact that solar energy practically does not enter the given area, this is observed in high latitudes. Thanks to the described fact, 4 important parallels are distinguished, which form 3 climatic zones on the planet:

  • The Tropic of Cancer (23o26 "14" "N) and the Tropic of Capricorn (23o26" 14 "" S) delimit the tropical climate zone.
  • The parallels 66oN and 66oS are called the North and South Polar Circle, respectively. Together with the tropics, they form a zone temperate climate in both hemispheres.
  • Cold polar belts lie between 66o and 90o of each hemisphere.

Longitude concept

After getting to know the question of what latitude is, let's move on to determining longitude. Geographic longitude is an angle that is described by the following three points:

  1. Its top is located on the axis of the Earth, perpendicular to the plane of the equator.
  2. The point on the surface that is the assumed reference origin.
  3. The point on the terrain, the longitude of which is determined.

All the named points lie in the same plane, that is, at the same latitude (two on the surface and one in the center of the Earth on its axis). The illustration in the first paragraph of the article will help you understand the concept of longitude.

In this definition, an important point is the choice of the reference point. At present, the longitude at which the Greenwich Observatory (London, England) is located is considered to be such throughout the world; the value of 0o is attributed to it. Note that different nations prior to the 19th century used their own zero longitude. For example, the Spaniards considered such an observatory in the city of Cadiz, and the French - an observatory in Paris.

What is a meridian?

When talking about latitude and longitude, many people think of parallels and meridians. The first has already been defined in the article. As for the meridian, it is understood as a line that connects the points of the north and south poles. Thus, all meridians are of the same length and they intersect the parallels at right angles.


The idea of ​​introducing a meridian is associated not only with the concept of longitude, but also with the time of day. Its name has Latin roots and means the middle of the day. Due to the rotation of the Earth around its axis, the Sun crosses all the meridians of our planet during the day as a result of its apparent movement across the sky. This fact allows us to introduce the concept of time zones, each of which occupies a strip of 15o (360o / 24 hours) width.


Longitude recording

If we go back to the definition of longitude, then in order to describe all points on a particular parallel, it is necessary to make a revolution of 360o. It is customary to describe longitude in the following ways:

  • One digit when moving east of the prime meridian (Greenwich Observatory). In this case, the longitude ranges from 0o to 360o.
  • From 0o to 180o, indicating the hemisphere (western (W or W) or eastern (B or E)).
  • 0o to 180o, using + for the eastern hemisphere and - for the western hemisphere.

Thus, records of longitude 270o, -90o and 90oW (90o3) are equivalent.

Geographical coordinates

Thus, in order to determine the position of an object on the ground, it is necessary to know its latitude and longitude coordinates. Let us give simple task: it is necessary to determine the coordinates of the capital of Russia, Moscow.

To solve the problem, we will use a map that shows the corresponding meridians and parallels. Below is an example of such a map, with which you can roughly determine the latitude and longitude of Moscow (Moscow).


The map shows that Moscow lies below 60oN, given the scale, we can say that its latitude is near 56oN. As for the longitude, it can be seen that the city lies to the right of 30oE. Given the scale, we get about 38oE. Thus, the coordinates of the capital of Russia are approximately equal to 56oN 38oE (or in the Russian version 56oС 38oВ). If you use a more accurate map, you can determine that the latitude and longitude of Moscow are 55o45 "N and 37o37" E.

History reference

Although the given definitions of the geographical coordinates of latitude and longitude are quite simple, in practice their measurement is a difficult task.


Until the 18th century, sailors could more or less accurately determine only the latitude, thanks to the measurement of the angle above the horizon of the North Star. As for the longitude, it was determined only approximately, using primitive tools, for example, a rope with knots for calculating the speed of a ship and an hourglass. Only with the invention of the chronometer at the end of the 18th century, mariners were able to determine the longitude of their location with good accuracy.

Since the time of man's departure to the sea, the need to determine longitude and latitude has been vital necessary skill person. Epochs changed, and man became able to determine the cardinal points in any weather. All new methods of determining one's position were required.

The captain of a Spanish galleon in the eighteenth century knew exactly where the ship was, thanks to the position of the stars in the night sky. A 19th-century traveler could determine the deviation from the established route in the forest using natural clues.

Now the twenty-first century is in the yard and many have lost the knowledge gained from the lessons of geography. Android smartphones or iPhones can serve as a tool, but will never replace the knowledge and ability to determine your location.

What is latitude and longitude in geography

Determination of geographic coordinates

Apps that users install on iPhones read location coordinates to provide services or data based on where the person is. After all, if the subscriber is in Russia, then he has no reason to read sites on English language... Everything happens in the background.

While the average user will never have to deal with GPS coordinates, knowing how to get and read them can be valuable. In some cases, they can save lives when there is no card nearby.

At any geographic system there are two indicators: latitude and longitude. Geodata from a smartphone show exactly where the user is in relation to the equator.

How to find the latitude and longitude of your location

Consider two options for determining geographic coordinates:

  1. Through "Android" the simplest is the Google Maps application, perhaps the most complete collection of geographic maps in one application. After starting the application Google maps the location on the road map so that the user can get the most out of the surrounding area. The app also offers an extensive list of features, including real-time GPS navigation, traffic status and transit information, and detailed information about nearby places, including popular food and recreation spots, photos and reviews.
  2. Through the "iPhone" no third-party application is required to view latitude and longitude data. The location is determined only with the maps app. To find out the current coordinates, just start the "maps". Tap the arrow in the upper right corner of the screen, then tap the blue dot - this is the location of the phone and the user. Then we swipe up the screen, and now the user can see the GPS coordinates. Unfortunately, there is no way to copy these coordinates, but you can get such data.

To copy them, you need another Compass application. It is already installed on the iPhone, you can use it right away.

To view latitude, longitude, and altitude coordinates in the Compass app, simply launch and find the data below.

Determine the geographical coordinates of Moscow

For this:

  1. We open the maps of the yandex search engine.
  2. Enter the name of our capital "Moscow" in the address line.
  3. The city center (Kremlin) opens and under the name of the country we find the numbers 55.753215, 37.622504 - these are the coordinates, that is, 55.753215 north latitude and 37.622504 east longitude.

All over the world, GPS coordinates are determined by latitude and longitude according to the wgs-84 coordinate system.

In all situations, latitude is a point relative to the equator and longitude is a point relative to the meridian of the British Royal Observatory in Greenwich, UK. This defines two important parameters of online geography.

Finding the latitude and longitude of St. Petersburg

To consolidate the skill, we repeat the same algorithm of actions, but for the Northern capital:

  1. We open "Yandex" cards.
  2. Prescribing the name of the northern capital "St. Petersburg".
  3. The result of the request will be a panorama of the Palace Square and the required coordinates 59.939095, 30.315868.

Coordinates of Russian cities and world capitals in the table

Cities of Russia Latitude Longitude
Moscow 55.753215 37.622504
Saint Petersburg 59.939095 30.315868
Novosibirsk 55.030199 82.920430
Yekaterinburg 56.838011 60.597465
Vladivostok 43.115536 131.885485
Yakutsk 62.028103 129.732663
Chelyabinsk 55.159897 61.402554
Kharkov 49.992167 36.231202
Smolensk 54.782640 32.045134
Omsk 54.989342 73.368212
Krasnoyarsk 56.010563 92.852572
Rostov 57.185866 39.414526
Bryansk 53.243325 34.363731
Sochi 43.585525 39.723062
Ivanovo 57.000348 40.973921
Capitals of world states Latitude Longitude
Tokyo 35.682272 139.753137
Brasilia -15.802118 -47.889062
Kiev 50.450458 30.523460
Washington 38.891896 -77.033788
Cairo 30.065993 31.266061
Beijing 39.901698 116.391433
Delhi 28.632909 77.220026
Minsk 53.902496 27.561481
Berlin 52.519405 13.406323
Wellington -41.297278 174.776069

Reading GPS data or where negative numbers come from

The geographic positioning system of the object was changed several times. Now thanks to her, you can quite accurately determine the distance to the desired object and find out the coordinates.

The ability to show the location is a vital necessity in the search activities of the rescue services. Different situations come with travelers, tourists or extreme sportsmen. It is then that high accuracy is important, when a person is on the brink of life, and the count goes by minutes.

Now, dear reader, having similar knowledge, you may have questions. There are many of them, but even from the table, one of the most interesting arises - why is the figure negative? Let's figure it out.

GPS when translated into Russian sounds like this - "global positioning system". Remember that the distance to the desired geographic object (city, village, village, etc.) is calculated according to two landmarks on the globe: the equator and the observatory in London.

At school, they talked about latitude and longitude, but in yandex maps they are replaced with the left and right parts of the code. If the navigator has positive values, then you are heading north. Otherwise, the numbers become negative, which indicates a southern latitude.

So it is with longitude. Positive values Is east longitude, and negative is west longitude.

For example, the coordinates of the Lenin Library in Moscow: 55 ° 45'08.1 ″ N 37 ° 36'36.9 ″ E. It reads like this: "55 degrees 45 minutes and 08.1 seconds north and 37 degrees 36 minutes and 36.9 seconds east" (data from the "google map").

Geographic longitude and latitude are used for precise definition the physical location of any object on the globe. The most in a simple way finding geographic coordinates is to use a geographic map. This method requires some theoretical knowledge to implement it. How to determine longitude and latitude is described in the article.

Geographical coordinates

Coordinates in geography are a system in which each point on the surface of our planet is assigned a set of numbers and symbols that allows you to accurately determine the position of that point. Geographic coordinates are expressed in three numbers - latitude, longitude, and altitude. The first two coordinates, that is, latitude and longitude, are most often used in various geographic tasks. The origin of the report in the geographic coordinate system is at the center of the earth. Spherical coordinates are used to represent latitude and longitude, which are expressed in degrees.

Before considering the question of how to determine longitude and latitude by geography, you should understand these concepts in more detail.

The concept of latitude

The latitude of a specific point on the surface of the Earth is understood as the angle between the equatorial plane and the line connecting this point with the center of the Earth. Through all points at the same latitude, you can draw a plane that will be parallel to the plane of the equator.

The equatorial plane is the zero parallel, that is, its latitude is 0 °, and it divides the entire globe into the southern and northern hemispheres. Accordingly, the north pole lies at the parallel of 90 ° north latitude, and the south pole lies at the parallel of 90 ° south latitude... The distance that corresponds to 1 ° when moving along a particular parallel depends on which parallel it is. With increasing latitude, moving north or south, this distance decreases. Thus, is 0 °. Knowing that the circumference of the Earth at the latitude of the equator has a length of 40075.017 km, we obtain a length of 1 ° along this parallel equal to 111.319 km.

Latitude indicates how far north or south a given point lies on the Earth's surface from the equator.

Longitude concept

The longitude of a specific point on the surface of the Earth is understood as the angle between the plane passing through this point and the axis of rotation of the Earth, and the plane of the prime meridian. According to the settlement agreement, the meridian is considered to be zero, which passes through the Royal Observatory at Greenwich, located in the southeast of England. Greenwich meridian divides the globe into eastern and

Thus, each line of longitude passes through the north and south poles. The lengths of all meridians are equal and amount to 40007.161 km. If we compare this figure with the length of the zero parallel, then we can say that the geometric shape of the planet Earth is a ball flattened at the poles.

Longitude indicates how far to the west or east of the prime (Greenwich) meridian a particular point on Earth lies. If latitude has a maximum value of 90 ° (latitude of the poles), then the maximum value for longitude is 180 ° west or east of the prime meridian. The 180 ° meridian is known as the International Date Line.

You can ask interesting question, the longitude of which points cannot be determined. Based on the definition of the meridian, we find that all 360 meridians pass through two points on the surface of our planet, these points are the south and north poles.

Geographic degree

From the above figures, it can be seen that 1 ° on the Earth's surface corresponds to a distance of more than 100 km, which is along the parallel, which is along the meridian. For more accurate coordinates of the object, the degree is divided into tenths and hundredths, for example, they say about 35.79 north latitude. In this form, information is provided by satellite navigation systems such as GPS.

Ordinary geographic and topographic maps fractions of a degree are represented as minutes and seconds. So, each degree is divided by 60 minutes (denoted by 60 "), and each minute is divided by 60 seconds (denoted by 60" "). Here you can draw an analogy with the representation of the measurement of time.

Acquaintance with the geographical map

To understand how to determine the geographical latitude and longitude on a map, you must first familiarize yourself with it. In particular, you need to figure out how the coordinates of longitude and latitude are represented on it. First, the top of the map shows the northern hemisphere, the bottom shows the southern. The numbers on the left and right on the edge of the map indicate latitude, and the numbers on the top and in lower parts maps are longitude coordinates.

Before determining the coordinates of latitude and longitude, you must remember that they are represented on the map in degrees, minutes and seconds. This system of units should not be confused with decimal degrees. For example, 15 "= 0.25 °, 30" = 0.5 °, 45 "" = 0.75 ".

Using a Geographic Map to Determine Longitude and Latitude

Let's explain in detail how to determine longitude and latitude from geography using a map. To do this, you first need to purchase a standard geographic map... This map can be a map of a small area, region, country, continent, or the entire world. To understand which card you have to deal with, you should read its name. Below, under the name, the limits of latitudes and longitudes can be given, which are presented on the map.

After that, you need to select some point on the map, some object that needs to be marked in some way, for example, with a pencil. How to determine the longitude of an object located at a selected point, and how to determine its latitude? The first step is to find the vertical and horizontal lines that lie closest to the selected point. These lines are latitude and longitude, the numerical values ​​of which can be viewed at the edges of the map. Suppose the selected point is between 10 ° and 11 ° N and 67 ° and 68 ° W.

Thus, we know how to determine the geographic latitude and longitude of the object selected on the map with the accuracy that the map provides. In this case, the accuracy is 0.5 °, both in latitude and longitude.

Determining the exact value of geographic coordinates

How to determine the longitude and latitude of a point more accurately than 0.5 °? First you need to find out what scale the map is on. Usually, a scale bar is indicated in one of the corners of the map, showing the correspondence of distances on the map to distances in geographic coordinates and in kilometers on the ground.

After the scale ruler is found, you need to take a simple ruler with millimeter divisions and measure the distance on the scale ruler. Let in the considered example 50 mm corresponds to 1 ° latitude and 40 mm - 1 ° longitude.

Now we place the ruler so that it is parallel to the longitude lines drawn on the map, and we measure the distance from the point in question to one of the nearest parallels, for example, the distance to the 11 ° parallel is 35 mm. We make a simple proportion and get that this distance corresponds to 0.3 ° from the parallel of 10 °. Thus, the latitude of the point in question is + 10.3 ° (plus sign means latitude north).

Similar steps should be taken for longitude. To do this, place the ruler parallel to the lines of latitude and measure the distance to the nearest meridian from the selected point on the map, for example, this distance is 10 mm to the meridian of 67 ° West longitude. According to the rules of proportion, we find that the longitude of the object in question is -67.25 ° (the minus sign means western longitude).

Converting the obtained degrees into minutes and seconds

As mentioned above, 1 ° = 60 "= 3600" ". Using this information and the rule of proportion, we find that 10.3 ° corresponds to 10 ° 18" 0 "". For the value of longitude, we get: 67.25 ° = 67 ° 15 "0" ". In this case, for the translation, the proportion was used once for longitude and latitude. However, in general case When, after using the proportion once, you get fractional minutes, you should use the proportion a second time to get the value of the added seconds. Note that the accuracy of determining coordinates up to 1 "corresponds to the accuracy on the surface the globe equal to 30 meters.

Recording the obtained coordinates

After the question of how to determine the longitude of the object and its latitude has been sorted out, and the coordinates of the selected point have been determined, they should be recorded correctly. The standard notation is longitude followed by latitude. Both values ​​must be specified with as many decimal places as possible, since the accuracy of the object location depends on this.

Certain coordinates can be represented in two different formats:

  1. Using only the degree icon, for example + 10.3 °, -67.25 °.
  2. Using minutes and seconds, for example, 10 ° 18 "0" "North, 67 ° 15" 0 "" West.

Note that when geographic coordinates are represented by degrees only, the words "north (south) latitude" and "east (west) longitude" are replaced with the appropriate plus or minus signs.

The position of each point on earth surface determine its coordinates: latitude and longitude (Fig. 3).

Latitude called the angle formed by the plumb line passing through a given point on the surface of the Earth, and the plane of the equator (in Fig. 3 for point M, the angle MOS).

Wherever the observer is on the globe, his gravity will always be directed towards the center of the earth. This direction is called vertical, or vertical.

Latitude is measured by the meridian arc from the equator to the parallel of a given point in the range from 0 to 90 ° and is denoted by the letter f. Thus, the geographic parallel eabq is the locus of points that have the same latitude.

Depending on which hemisphere the point is in, the latitude is named north (N) or south (S).

Longitude called the dihedral angle between the planes of the initial meridian and the meridian of a given point (in Fig. 3 for point M, the angle AOS). Longitude is measured by the lesser of the arcs of the equator between the initial meridian and the meridian of a given point in the range from 0 to 180 ° and is denoted by the letter L. Thus, the geographic meridian of PN MCPs is the locus of points with the same longitude.

Depending on which hemisphere the point is in, the longitude is called east (O st) or west (W).

Latitude difference and longitude difference

During the voyage, the vessel continuously changes its position on the surface of the Earth, therefore, its coordinates also change. The magnitude of the change in latitude Af, resulting from the transition of the vessel from the point of departure MI to the point of arrival C1, is called latitude difference(RSh). RS is measured by the meridian arc between the parallels of the departure and arrival points M1C1 (Fig. 4).


Rice. 4


The name of the RSh depends on the location of the parallel of the point of arrival relative to the parallel of the point of departure. If the parallel of the arrival point is north of the parallel point of departure, then the RS is considered made to N, and if to the south, then to S.

The magnitude of the change in longitude Al, resulting from the transition of the vessel from the point of departure M1 to the point of arrival C2, is called difference in longitudes(RD). The taxiway is measured by the smaller arc of the equator between the meridians of the point of departure and the point of arrival of the MCN (see Fig. 4). If during the passage of the ship the east longitude increases or the west decreases, then the taxiway is considered to be made to O st, and if the east longitude decreases or the west increases, then to W. To determine the RS and taxiways, use the formulas:

РШ = φ1 - φ2; (one)

RD = λ1 - λ2 (2)

Where φ1 is the latitude of the point of departure;

φ2 - latitude of the point of arrival;

λ1 - longitude of the point of departure;

λ2 - longitude of the point of arrival.

In this case, the northern latitudes and eastern longitudes are considered positive and a plus sign is assigned to them, and the southern latitudes and western longitudes are negative and a minus sign is assigned to them. When solving problems according to formulas (1) and (2), in the case of positive results of RS it will be made to N, and RD - to O st (see example 1), and in the case of negative results of RS it will be to S, and RD - to W (see example 2). When receiving a taxiway result of more than 180 ° s negative sign you need to add 360 ° (see example 3), and if the taxiway result is more than 180 ° with a positive sign, you need to subtract 360 ° (see example 4).

Example 1. Known: φ1 = 62 ° 49 "N; λ1 = 34 ° 49" O st; φ2 = 72 ° 50 "N; λ2 = 80 ° 56" O st.

Find RSH and RD.

Solution.


Example 2. Known: φ1 = 72 ° 50 "N; λ1 =: 80 ° 56" O st: φ2 = 62 O st 49 "N;

Find RSH and RD.

Geographic coordinates consist of two components: latitude and longitude, angular values, using which each person can determine the location of any object on the world map. The study of the latitude and longitude of the globe was carried out in ancient times.

Geographic latitude concept

Latitude is a geographic coordinate in a number of spherical coordinate systems that defines points located on the Earth's surface relative to the equator. Geographic latitude objects that are located in the northern hemisphere are considered positive, in the southern hemisphere - negative.

In geography, there is the concept of southern and northern latitudes. Determining which latitude is south and which is north is simple: if the point moves from the equator to the side North Pole, it falls into the zone of northern latitudes.

Latitudes on the map are depicted by lines running parallel to the equator and to each other, hence the name of these lines - parallels. The distance between parallels is not measured in kilometers, but in degrees, in minutes and seconds.

Each degree has 60 minutes, 1 minute has 60 seconds. The equator is latitude zero, North and South Pole located at 90 degrees north and 90 degrees south latitude, respectively.

One degree of geographic longitude is equal to 1/360 of the length of the equator.

Geographic longitude concept

Longitude is a coordinate in a geographic coordinate system that defines the location of a point relative to the prime meridian. Thanks to longitude, we can find out the position of an object relative to the west and east.

In geographical science, the Greenwich Laboratory, which is located in the east of London (Greenwich meridian), is considered to be the zero point of geographic longitude.

The lines that define longitude are called meridians. All meridians run perpendicular to the equator line. All meridians intersect at two points - at the North and South Pole.

The territories located east of the Greenwich meridian are called the region of eastern longitudes, territories in the western direction are called the region of western longitudes.

Most of the continents are located in the region of eastern longitudes, with the exception of only two continents - South and North America... Points that are located on the meridians have the same longitude, but different latitudes.

1/180 of the meridian is one degree of latitude. The average length of one degree of latitude becomes about 111 km. Indicators of east longitude are considered positive, indicators of west longitude - negative.