View from space

The 20th century was the century of the launch of the first artificial Earth satellite, the first human flight into space, landing on the Moon and flights to the planets of the solar system. If Yu. A. Gagarin's flight into space was a world sensation, then today's flights have already become something commonplace, a matter of course. A look at the Earth from space, space photography of the planet’s surface is part of the working moments of astronauts.

Using images from space, you can track the shape of continents and oceans, you can see what state nature is in, you can tell about the upcoming weather, you can trace ocean currents, emerging vortices, you can directly observe everything that could not be done before.

Thus, today we can already talk about the birth of a new science - space geography. The first human flight into space was the beginning of the formation of knowledge of space geography.

To date, a huge fund of images from space has been accumulated, having different levels of detail and scale, and various video and photographic materials have been accumulated.

Note 1

It must be admitted that these materials are understandable only to specialists and are used to solve narrow specialized problems, in geology, for example, to clarify the structural-geological structure and search for minerals, in education to obtain interpretation skills.

Artificial Earth satellites perform very important tasks; they help determine the distribution of snow cover and water reserves in glaciers. Permafrost is studied using space geography.

With its help, a large amount of material has been collected about the variety of types and forms of relief, especially very large forms that cannot be covered from the Earth.

Images from space have revealed curved arc-shaped stripes in the deserts of North Africa, stretching for tens of kilometers in the direction of the blowing winds.

A view from space allowed scientists to find out that the entire planet is cut up by clayey faults, and among them there are “transparent” faults through a thick layer of loose sediments. Other images provide assistance in identifying minerals. Of course, doing such work while on Earth is very difficult, and sometimes simply impossible.

Meteorological satellites survey a vast area and monitor all phenomena occurring in the atmosphere, which is important when making weather forecasts.

Information about the energy sector of the planet, i.e. How much solar energy different parts of the Earth receive and what the loss of thermal radiation in space is equal to is also provided by satellites. Based on these data, scientists found that the planet is warmer and darker, but previously science had other data.

Space geography is quite successfully used in studying the flora of the Earth. From space, it is possible to determine the boundaries of vegetation zones much more accurately, which means that their changes can also be monitored.

Note 2

Thus, today it has become possible to determine from space all the changes occurring in nature and take appropriate measures already on Earth. Space geography helps scientists monitor the dynamics of natural processes and their frequency, and provides photographs of the same areas at different periods of time.

Space geography and modern sciences

Images of the Earth's surface from space are of great interest for science and the national economy. They provide new information about the planet.

Meteorologists were the first to use images of the Earth from space. Photographs of cloudiness convinced them of the correctness of the hypotheses about the physical state of the atmosphere, about the presence of cells with ascending and descending flows of air masses. Based on satellite images and their use, meteorologists solve the most difficult task of science - compiling 2-3 week weather forecasts.

Space photographs are also successfully and effectively used in geology. They help supplement and clarify geological maps and help develop new methods for searching for minerals. For example, observations from space helped to detect large faults in Kazakhstan and Altai, and this indicates their ore potential. Scientists, having such information, drew up a master plan for search work.

By studying the earth's crust using space photographs, hidden deep faults and huge ring formations were discovered. Scientists continue to study the geological structure of ocean shallows and the continental shelf.

A view of the Earth from above provides information about the characteristics of regions, allows you to clarify existing information or draw up new geological maps.

Space observations help in solving agricultural problems - using images you can monitor:

moisture reserves in the soil,
the condition of the crops,
use of pastures.

In arid regions, it is possible to detect groundwater at shallow depths.

With the help of space information, it becomes possible to keep records and assess land, and to determine areas affected by agricultural pests. In forestry, satellite imagery helps to develop a method of forest accounting, this is a problem facing forestry. Using images, they not only conduct an inventory of forest resources, but even calculate wood reserves.

Space methods are used to study the World Ocean; the images clearly show ocean currents and the speed of their movement, and the presence of sea waves in the ocean. Ice maps compiled from images are used in navigation, maps of the ocean surface help in organizing fishing.

Archaeologists also did not stand aside, extracting scientifically valuable information from the images. Traces of the past, buried from the eyes of scientists, also help to discover space images; for example, in the Kalmyk Trans-Volga region, thanks to photographs from orbit, numerous ancient settlements located underground were discovered. The photographs show once-paved roads and flowing rivers.

Today, for filming from space, the multispectral space camera MKF-6 is widely used, in the development of which specialists from the USSR and the GDR took part.

The device has 6 cameras and conducts spectrozonal photography in 6 ranges of the electromagnetic spectrum. In photographs taken by this device, only those objects that reflect electromagnetic waves of a certain length are visible.

Space cartography

Images from space have found application in cartography, and this is completely natural, because they capture the surface of the Earth in great detail, and specialists quite easily transfer these images to a map.

Note 3

Space images are deciphered using identification features, the main of which are the shape of the object, its size and tone.

For example, water bodies – lakes, rivers – are depicted in photographs in dark (black) tones, with the banks clearly visible. Forest vegetation has less dark tones of a fine-grained structure, and mountain relief stands out in sharp contrasting tones due to the different illumination of the slopes. Roads and settlements have their own decoding signs.

By comparing a map and a satellite image, you can find out additional information about the area - the information from the satellite image is more detailed and up-to-date.

Maps are compiled from photographs in the same way as from aerial photographs, using various methods using photogrammetric instruments.

A simpler option is to make a map to the scale of the photograph - objects are first copied onto tracing paper, and then transferred from tracing paper to paper. They, however, show only the contours of the area, are not tied to a cartographic grid, and their scale is arbitrary, which is why they are called map diagrams.

Space images are used in cartography to create small-scale maps, and today a variety of thematic maps have already been created.

Map information is gradually becoming outdated because the appearance of the Earth is constantly changing. Images from space make it possible to correct maps and update information, since it is reliable and the latest.

Space photographs are used not only to map the surface of the Earth; they are used to create maps of the Moon and Mars. Despite the fact that the lunar map is more detailed, the map of Mars quite clearly and accurately depicts the Martian surface.

Human spaceflight has made it possible to get to know our planet even better. The information provided about her is numerous and varied. But we are, of course, interested in those that relate to human habitats - the air basin and subsoil, vegetation cover and soils.

Using images from space in cartography

As the flow of cosmic energy intensifies, the scope of its application expands. Currently, to one degree or another, it is used in almost all sectoral and complex geographical studies. As for cartography, space images are just beginning to be studied. Nevertheless, it is already possible to indicate areas where it will find application in the near future. This is primarily in the depiction of the coastal zone of seas and lakes, flooded areas and coastal vegetation, as well as settlements, communications routes, etc.

It is estimated that the use of satellite images for these purposes provides significant savings in costs, labor costs and time.

Abroad, for example in the USA, there is experience in creating general geographic maps of little-explored territories using satellite images, in particular in. Based on satellite images, a map was made at a scale of 1:250,000.

Space images have found application in the production of intermediate cartographic documents - photo maps. They can only contain a photographic (from space) image of the earth’s surface, supplemented with elements from traditional maps: general geographical, geological, geomorphological, etc.

Photo maps have independent significance as sources for studying the earth's surface for various purposes of its economic use. They serve to update and improve traditional nature maps, but cannot replace them themselves.

Although satellite images are currently widely used in various studies of natural phenomena and processes, experimental work does not lead to the creation of fundamental maps of large spatial coverage. Conditions are apparently not yet ripe for this. Nevertheless, there is some experience in compiling nature maps using satellite images. It is known that the television program “Time” ends with a message from the Russian Hydrometeorological Center about the weather forecast. Often, synoptic maps are shown, which are compiled taking into account data received from satellites.

Today, meteorological research in our country is carried out with the widespread use of information received from meteorological satellites of the Earth. The Hydrometeorological Center of Russia compiles global maps of cloudiness for different dates. And analysis of cloud cover using maps helps to study many atmospheric processes: jet streams in the subtropics, air currents in the upper troposphere, tropical storms, etc. Using cloud cover maps, a method for estimating monthly precipitation amounts has been proposed. Abroad, maps of ocean surface temperatures have been compiled using satellite images.

However, all this work relates to the so-called operational mapping, i.e., to obtaining maps for immediate and short-term use in the interests of a particular government service or department.

As for the compilation of fundamental thematic maps of large territorial coverage from space images, back in the USSR, on the initiative of Soviet geologists, work was carried out to create a map of faults of the USSR and neighboring countries on a scale of 1: 2,500,000. This, in essence, was the first experience in using space information in thematic cartography. This work was carried out at the State Research and Production Center “Priroda”.

Abstract on the discipline

"Geography"

On this topic:

“Space photography. Types and properties of space images, their application in cartography"

Content

Introduction (p.3)

Types of filming (c.6)

Space cartography (p.8)

Monitoring the environment from space (p.12)

Conclusion (p.15)

References (p. 16)

Introduction

Goal of the work: consideration of the essence of space photography.

Space photography is a technological process of photographing the earth's surface from an aircraft in order to obtain photographic images of the area (photographs) with specified parameters and characteristics. The main tasks of space photography include: research of the planets of the solar system; study and rational use of the Earth's natural resources; study of anthropogenic changes in the earth's surface; exploration of the World Ocean; air and ocean pollution research; environmental monitoring; study of shelf and coastal waters .

The main difference between photographing from space is: high altitude, flight speed and their periodic change as the spacecraft moves in orbit; rotation of the Earth, and, consequently, of the objects being photographed relative to the orbital plane; rapid change in the illumination of the Earth along the flight path of the spacecraft; photographing through the entire layer of the atmosphere; photographic equipment is fully automated. A high shooting altitude causes the image to be zoomed out. The choice of orbital altitude is carried out based on the tasks that are solved during photography and the need to obtain photographic images of a certain scale. In this regard, the requirements for the optical system of cameras are increasing in terms of image quality, which must be good throughout the entire field. The requirements for geometric distortions are especially high.

We are witnessing how man is gradually mastering the near-Earth space and how automata sent from Earth are successfully studying other planets of the solar system. Artificial satellites created by people and launched into space transmit to Earth photographs of our planet taken from great heights.

So today we can sayabout space geodesy , or, as it is also called, satellite geodesy. We are witnessing the emergence of a new section of cartography, which it would be fashionable to callspace cartography.

Already today, images taken from space are used to make changes in the content of maps, being the most rapid means of identifying these changes. Further development of space cartography will lead to even more significant results.

The significance and advantage of images of the Earth from Space compared to conventional aerial photographs are undeniable. First of all, their visibility - images from heights of hundreds and thousands of kilometers make it possible to obtain both images covering aerial photography and images of an area extending hundreds and thousands of kilometers. In addition, they have the properties of spectral and spatial generalization, i.e., screening out the secondary, random and highlighting the essential, the main. Space photography makes it possible to obtain images at regular intervals, which in turn makes it possible to study the dynamics of any process.

The possibility of obtaining satellite images has led to the emergence of a number of new thematic maps - maps of such phenomena, the numerous characteristics of which are practically impossible to obtain by other methods. Thus, for the first time in the history of science, global maps of cloud cover and ice conditions were compiled. Satellite images are indispensable when studying the dynamics of atmospheric processes - tropical cyclones and hurricanes. For these purposes, photography from ceostationary satellites is especially effective - satellites “motionlessly” hovering over one point on the Earth’s surface, or, more precisely, moving along with the earth at the same angular velocity.

Satellite images provided fundamentally new information to geologists. They made it possible to increase the depth of research and gave rise to a new type of cartographic works - “cosmophotogeological” maps. The most important advantage of satellite images is the ability to show on them new features of the structure of territories that are invisible on conventional aerial photographs. It is the filtration of small details that leads to the spatial organization of devastated fragments of large geological formations into a single whole. Linear discontinuities, called lineaments, clearly visible in photographs, cannot always be detected during direct field surveys. Lineament maps provide significant assistance in deep exploration of minerals. Previously unknown geological structures were discovered in this way in the middle reaches of the Vilyuya.

Images from space are now intensively used in glaciology; they are the main source material. Practically, all space pioneers, especially participants in long-term space flights, successfully solve various thematic mapping problems. In our country, forests occupy more than half of the territory . Information on the many characteristics of this forest fund is enormous and must be updated regularly. Gigantic volumes of operational, comprehensive and at the same time detailed information are unthinkable without the help of astronauts and space photography. Practice has already proven that space mapping of forests is a necessary link in their study and resource management. Regular space mapping of changes occurring in forests is very important for preventing and localizing harmful impacts and solving environmental protection problems. Only with the help of space technology is it possible to obtain information about the sanitary condition of forests, and with the help of daily surveys from Meteor satellites, data on the fire situation in forests can be obtained.

Space-based continuous mapping of the state of the environment is today referred to as “monitoring.” The range of means and methods of a cartographer is becoming wider: from cosmic heights to underwater depths, but everywhere - at the control panel of a space topographer - a planetary rover, at an ordinary theodolite, there is a person creating a map.

Types of filming.

Space photography is carried out using different methods (Fig. “Classification of space images by spectral ranges and imaging technology”).

The nature covering the earth's surface with satellite images, the following surveys can be distinguished:

single photograph,

route,

sighting,

global survey.

Single (selective) photography is carried out by astronauts with hand-held cameras. The photographs are usually taken in perspective with significant angles of inclination.

Route shooting the earth's surface is carried out along the satellite flight path. The width of the shooting swath depends on the flight altitude and viewing angle of the shooting system.

Sighting (selective) shooting designed to obtain images of specially designated areas of the earth's surface away from the route.

Global filming produced from geostationary and polar-orbiting satellites. satellites. Four or five geostationary satellites in equatorial orbit provide almost continuous acquisition of small-scale survey images of the entire Earth (space patrol) with the exception of the polar ice caps.

Aerospace photo is a two-dimensional image of real objects, which is obtained according to certain geometric and radiometric (photometric) laws by remotely recording the brightness of objects and is intended for studying visible and hidden objects, phenomena and processes of the surrounding world, as well as for determining their spatial position.

A satellite image in its geometric properties is not fundamentally different from an aerial photograph, but has features associated with:

photographing from high altitudes,

and high speed.

Since a satellite moves much faster compared to an airplane, it requires short shutter speeds when shooting.

Space photography varies according to:

scale,

spatial resolution,

visibility,

spectral characteristics .

These parameters determine the possibilities of interpreting various objects in satellite images and solving those geological problems that are advisable to solve with their help.

Space cartography

Space images are especially widely used in cartography. And this is understandable, because a space photograph accurately and in sufficient detail captures the surface of the Earth, and specialists can easily transfer the image to a map.

Reading (deciphering) of space images, as well as aerial photographs, is based on identification (deciphering) features. The main ones are the shape of objects, their size and tone. Rivers, lakes and other bodies of water are depicted in photographs in dark tones (black) with clear identification of coastlines. Forest vegetation is characterized by less dark tones with a fine-grained structure. The details of the mountainous terrain are clearly highlighted by the sharp contrasting tones that are obtained in the photograph as a result of the different illumination of the opposite slopes. Settlements and roads can also be identified by their decryption characteristics, but only under high magnification. This cannot be done on printed copies.

The use of satellite images for cartographic purposes begins with determining their scale and linking them to a map. This work is usually carried out on a map of a smaller scale than the scale of the image, since it is necessary to plot the boundaries of not one, but a whole series of images.

By comparing a photograph with a map, you can find out what is shown in the photograph and how it is shown, how it is shown on the map, and what additional information about the area is provided by a photographic image of the earth’s surface from space. And even if the map is the same scale as the photograph, you can still obtain more extensive and, most importantly, up-to-date information about the area from the photograph compared to the map.

Mapping from satellite images is carried out in the same way as from aerial photographs. Depending on the accuracy and purpose of maps, various methods are used to compile them using appropriate photogrammetric instruments. It is easiest to make a map to the scale of the photograph. It is these cards that are usually placed next to photographs in albums and books. To compile them, it is enough to copy images of local objects onto tracing paper from a photograph, and then transfer them from tracing paper to paper.

Such cartographic drawings are called maps. They display only the contours of the terrain (without relief), have an arbitrary scale and are not tied to a cartographic grid.

In cartography, satellite images are used primarily to create small-scale maps. The advantage of space photography for these purposes is that the scale of the images is similar to the scale of the maps being created, and this eliminates a number of rather labor-intensive compilation processes. In addition, space images seem to have passed the path of primary generalization. This occurs as a result of photography being done on a small scale.

Currently, various thematic maps have been created using satellite images. In some cases, the characteristics of some phenomena can be determined only from satellite images, and it is impossible to obtain them by other methods. Based on the results of space photography, many thematic maps have been updated and detailed, and new types of geological landscape and other maps have been created. When compiling thematic maps, images taken in different spectral zones are especially useful, as they contain rich and varied information.

Space images have found wide application in the production of intermediate cartographic documents - photo maps. They are compiled in the same way as photographic plans, by mosaic gluing together individual photographs on a common basis. Photo cards can be of two types: some show only a photographic image, while others are supplemented with individual elements of regular cards. Photographic maps, like individual photographs, serve as valuable sources for studying the earth's surface. At the same time, they are additional material to a regular map and cannot fully replace it.

The appearance of the Earth is constantly changing, and any map is gradually aging. Satellite images contain the latest and most reliable information about the area and are successfully used to update not only small-scale but also large-scale maps. They allow you to correct maps of large areas of the globe. Space photography is especially effective in hard-to-reach areas, where field work requires a lot of effort and money.

Photography from space is used not only for mapping the earth's surface. Maps of the Moon and Mars were compiled from space photographs. When creating the map of the Moon, data obtained from the automatic self-propelled vehicles Lunokhod-1 and Lunokhod-2 were also used. How was filming carried out with their help? When the self-propelled vehicle moved, a so-called survey course was laid. Its purpose is to create a frame relative to which the topographic situation will be plotted on the future map. To construct the course, the lengths of the traversed sections of the path and the angles between them were measured. From each position of the Lunokhod, television filming of the area was carried out. Television images and measurement data were transmitted via radio to Earth. Here processing was carried out, as a result of which plans were drawn up for individual sections of the area. These separate plans were tied to the shooting progress and combined.

The map of Mars, compiled from space images, is less detailed compared to the map of the Moon, but still it clearly and quite accurately displays the surface of the planet (Fig. 55). The map is made on thirty sheets on a scale of 1:5000000 (1 cm 50 km). Two circumpolar sheets are compiled in an azimuthal projection, 16 near-equatorial sheets are in a cylindrical projection, and the remaining 12 sheets are in a conical projection. If all the sheets are glued together, you will get an almost regular ball, i.e. the globe of Mars.

Rice. 55. Fragment of a photo map of Mars

The basis for the map of Mars, as well as for the map of the Moon, was the photographs themselves, in which the surface of the planet is depicted with side lighting directed at a certain angle. The result is a photo map on which the relief is depicted in a combined way - horizontal lines and natural shadow coloring. On such a photo map, not only the general nature of the relief is clearly visible, but also its details, especially craters, which cannot be depicted as horizontal lines, since the height of the relief section is 1 km.

The situation with photographing Venus is much more complicated. It cannot be photographed in the usual way, because it is hidden from optical observation by dense clouds. Then the idea arose to make her portrait not in light, but in radio rays. For this purpose, they developed a sensitive radar that could, as it were, probe the surface of the planet.

To see the landscape of Venus, you need to bring the radar closer to the planet. This is what the automatic interplanetary stations Venera-15 and Venera-16 did.

The essence of radar survey is as follows. The radar installed at the station sends radio signals reflected from Venus to Earth to the radar information processing center, where a special electronic computing device converts the received signals into a radio image.

From November 1983 to July 1984, the Venera-15 and Venera-16 radars photographed the northern hemisphere of the planet from the pole to the thirtieth parallel. Then, using a computer, a photographic image of the surface of Venus was applied to the cartographic grid and, in addition, a relief profile was constructed along the station’s flight line.

Monitoring the environment from space

Currently, the problem of environmental protection is global. That is why space-based control methods are becoming increasingly important, making it possible to increase the volume of research and speed up the acquisition and processing of data. The main means of monitoring is a system of space surveys based on a network of ground stations. This system includes photography from artificial Earth satellites, manned spacecraft and orbital stations. The resulting photographic images are sent to ground receiving centers, where the information is processed.

What is visible on satellite images? First of all, almost all forms and types of environmental pollution. Industry is the main source of environmental pollution. The activities of most industries are accompanied by waste emissions into the atmosphere. The images clearly show plumes of such emissions and smoke screens stretching for many kilometers. When the concentration of pollution is high, even the earth's surface cannot be seen through it. There are known cases where vegetation over an area of several square kilometers died near some North American metallurgical enterprises. This is already affected not only by the impact of harmful emissions, but also by soil and groundwater pollution. These areas appear in photographs as a faded, dry, lifeless semi-desert among forests and steppes.

The photographs clearly show suspended particles carried by rivers. Heavy pollution is especially typical for delta sections of rivers. This is caused by coastal erosion, mudflows, and hydraulic engineering works. The intensity of mechanical pollution can be determined by the image density of the water surface: the lighter the surface, the greater the pollution. Shallow water areas also stand out in the images as light spots, but unlike pollution, they are permanent in nature, while the latter change depending on meteorological and hydrological conditions. Space photography has made it possible to establish that mechanical pollution of water bodies increases in late spring, early summer, and less often in autumn.

Chemical pollution of water areas can be studied using multispectral images that record how depressed aquatic and coastal vegetation is. The images can also be used to establish biological contamination of water bodies. It reveals itself by the excessive development of special vegetation, visible in photographs in the green region of the spectrum.

The release of warm water into rivers by industrial and energy enterprises is clearly visible in infrared images. The boundaries of the distribution of warm water make it possible to predict changes in the natural environment. For example, thermal pollution disrupts the formation of ice cover, which is clearly visible even in the visible range of the spectrum.

Forest fires cause great damage to the national economy. From space they are visible primarily due to the smoke plume, sometimes stretching for several kilometers. Space photography allows you to quickly determine the extent of fire spread. In addition, satellite images help to detect nearby clouds, from which heavy rain is caused using special reagents sprayed in the air.

Space images of dust storms are of great interest. For the first time, it became possible to observe their origin and development, to monitor the movement of dust masses. The front of a dust storm can reach thousands of square kilometers. Most often, dust storms sweep over deserts. A desert is not a lifeless land, but an important element of the biosphere and therefore needs constant monitoring.

Now let's move to the north of our country. People often ask why there is so much talk about the need to protect the nature of Siberia and the Far East? After all, the intensity of the impact on it is still many times less than in the central regions.

The fact is that the nature of the North is much more vulnerable. Anyone who has been there knows that after an all-terrain vehicle passes through the tundra, the soil cover is not restored and surface erosion develops. The purification of water basins occurs tens of times slower than usual, and even a small newly paved road can cause a difficult-to-reversible change in the natural situation.

The northern territories of our country extend over 11 million km 2 . This is taiga, forest-tundra, tundra. Despite the difficult living conditions and logistical difficulties, more and more cities are appearing in the North, and the population is increasing. In connection with the intensive development of the territory of the North, the lack of initial data for the design of settlements and industrial facilities is especially acute. That is why space exploration of these areas is so relevant today.

Currently, two related methods - cartographic and aerospace - closely interact in the study of nature, economy and population. The prerequisites for such interaction are embedded in the properties of maps, aerial photographs and satellite images as models of the earth's surface.

Conclusion

Space surveys solve various problems related to remote sensing of the earth and indicate their wide capabilities. Therefore, space methods and means already today play a significant role in the study of the Earth and near-Earth space. Technologies are moving forward, and in the near future their importance for solving these problems will increase significantly.

Bibliography

Bogomolov L. A., Application of aerial photography and space photography in geographical research, in the book: Cartography, vol. 5, M., 1972 (Results of science and technology).

Vinogradov B.V., Kondratiev K.Ya., Space methods of geoscience, Leningrad, 1971;

Kusov V. S. “The map is created by pioneers”, Moscow, “Nedra”, 1983, p. 69.

Leontiev N. F. “Thematic cartography” Moscow, 1981, from. "Science", p.102.

Petrov B. N. Orbital stations and studying the Earth from space, “Vestn. Academy of Sciences of the USSR", 1970, No. 10;

Edelshtein, A. V. “How a map is created”, M., “Nedra”, 1978. c. 456.

Abstract on the discipline

"Geography"

On this topic:

“Space photography. Types and properties of space images, their application in cartography"

Content

Introduction (p.3)

Types of filming (c.6)

Space cartography (p.8)

Monitoring the environment from space (p.12)

Conclusion (p.15)

References (p. 16)

Introduction

Goal of the work: consideration of the essence of space photography.

Types of filming.

Space photography is carried out using different methods (Fig. “Classification of space images by spectral ranges and imaging technology”).

The nature covering the earth's surface with satellite images, the following surveys can be distinguished:

single photograph,

route,

sighting,

global survey.

Single (selective) photography is carried out by astronauts with hand-held cameras. The photographs are usually taken in perspective with significant angles of inclination.

Route shooting the earth's surface is carried out along the satellite flight path. The width of the shooting swath depends on the flight altitude and viewing angle of the shooting system.

Sighting (selective) shooting designed to obtain images of specially designated areas of the earth's surface away from the route.

A satellite image in its geometric properties is not fundamentally different from an aerial photograph, but has features associated with:

photographing from high altitudes,

and high speed.

Since a satellite moves much faster compared to an airplane, it requires short shutter speeds when shooting.

Space photography varies according to:

scale,

spatial resolution,

visibility,

spectral characteristics .

These parameters determine the possibilities of interpreting various objects in satellite images and solving those geological problems that are advisable to solve with their help.

Space cartography

Such cartographic drawings are called maps. They display only the contours of the terrain (without relief), have an arbitrary scale and are not tied to a cartographic grid.

Rice. 55. Fragment of a photo map of Mars

To see the landscape of Venus, you need to bring the radar closer to the planet. This is what the automatic interplanetary stations Venera-15 and Venera-16 did.

Monitoring the environment from space

Conclusion

Bibliography

Bogomolov L. A., Application of aerial photography and space photography in geographical research, in the book: Cartography, vol. 5, M., 1972 (Results of science and technology).

Vinogradov B.V., Kondratiev K.Ya., Space methods of geoscience, Leningrad, 1971;

Kusov V. S. “The map is created by pioneers”, Moscow, “Nedra”, 1983, p. 69.

Leontiev N. F. “Thematic cartography” Moscow, 1981, from. "Science", p.102.

Petrov B. N. Orbital stations and studying the Earth from space, “Vestn. Academy of Sciences of the USSR", 1970, No. 10;

Edelshtein, A. V. “How a map is created”, M., “Nedra”, 1978. c. 456.

kov with the presentation of measurement results in a form that is clear and convenient for visual analysis - in the form of special dynamics maps.

3.4. Aerospace mapping for geographic research

Making maps from photographs. In aerospace thematic mapping performed during geographical research, images are used: 1) to prepare the topographic basis of a future map and 2) as a source of its content. To solve the first problem, satellite images must be brought to a certain scale and projection. This is achieved by transforming photographs, which are then mounted into photo plans and photo cards.

The contents of the map are obtained from images during the decryption process, using all available methods of information extraction, including computer processing. Obviously, for decoding it is necessary to select images of such scale and resolution that the generality of the image corresponds to the required generalization of the content of the map. Here, relying on the geographic resolution of the images is useful, which helps determine the optimal type of images to solve a specific problem.

Depending on the topic, scale and purpose of the map, in addition to the main image, you can also use a set of aerospace images of different scales, providing the study of natural and socio-economic objects at several hierarchical levels. The scale of the main original satellite image (usually high-resolution images are used) is usually several times smaller than the scale of the map being compiled, and visual interpretation work is carried out using images with a large (5-10 times) magnification, which ensures a more complete extraction of information.

The technological scheme for creating a map from aerospace images, determined by the map program, may change depending on specific conditions, but it always involves performing such work as spatial (geographic) referencing of images and preparation of the base; decryption; transferring the decoding results to the base and drawing up the original map.

Cartographic generalization when moving from image to map.

The image of aerospace images is saturated with a significantly greater amount of detail than can be conveyed graphically when drawing up a map from the image. Therefore, the process of generalization is inevitable when moving from an image to a map.

In topographic mapping, where the creation of topographic maps from aerial photographs represents a mass production process, the rules of generalization and selection qualifications when moving from image to map are formulated in the corresponding manuals and guidelines. The principles and rules of such generalization are close to those well developed in cartography and are aimed at discarding unimportant details while preserving the most important elements and displaying typical features of the structure of the territory.

A lot of image details are excluded, representing information unnecessary for solving the main decoding task. Objects that served as indicators, but were not themselves objects of study, recede into the background. For example, a geomorphologist, identifying lineaments, does not draw a river with all its bends from a photograph, but identifies straightened sections that emphasize the fault he is deciphering. When deciphering, he omits the grid of fields and the contours of forests, which do not help identify the geological objects that are important to him.

Thus, targeted selection of decipherable elements is the main aspect of generalization during decoding. Another function of generalization is determined by the excessive detail of the image of the deciphered elements in the image, which cannot be conveyed graphically, ensuring the readability of the map. With inevitable simplification, it is important to preserve the natural pattern in the drawing of deciphered contours and not lose it during schematization. This pattern is unique for various landscapes. For example, in tundra landscapes it is important to convey a spotted pattern created by a system of rounded small lakes in thermokarst relief, and in the eroded areas of the Central Chernozem Region - a complex system of tree-like dissection of the relief by a gully-beam network, which determines the spatial image of these territories.

The fairly strict selection criteria given in production documents for creating maps should be modified depending on the purposes of the study. For example, in order to convey the phases of development of the frozen-thermokarst relief from young to mature and decrepit (thermokarst lakes - lakes with a border of alas - alas with residual lakes - dry alas), it is important to preserve even a narrow border of alas around the lakes in the second stage, and in the third - even very small lakes, since it is their presence that separates these stages.

Thus, correct generalization is based on a detailed study of the geographical landscape, its typical and characteristic features, on identifying regional features of the territory from photographs, and individual features of the design of various objects. It is solved by selecting individual objects until

figures and characteristics, generalization of outlines, exaggeration of the image (deliberate exaggeration of the size of its elements) taking into account the purposes of the study and the regional characteristics of the territory.

Card requirements created from photographs, the requirements are the same as for all maps: it must have a mathematical basis in the form of a coordinate grid or signed grid outputs, an indication of the scale. With the now widespread computer methods of preparing the original map, it is necessary to have a linear scale designation on the map. The design and methods of depicting content extracted from photographs may vary. The results are presented in different forms - in the form of a thematic photo map, when the image of the photograph is supplemented with the boundaries of deciphered contours or individual objects with digital indices; in the form of a “classified image” - the results of computer classification and, finally, in the form of a traditional map with selected contours of objects and their coloring using a high-quality background method. An absolutely necessary element of the map is a legend that meets cartographic rules - constructed in strict compliance with the logic of classification of the depicted phenomena and their hierarchical subordination. This is often forgotten when creating maps on a computer, using legend building software modules that, as a rule, do not meet these professional requirements.

Maps compiled from images are, as a rule, more detailed and better reflect the spatial patterns of distribution of the objects under study, but the completeness and reliability of their content is ensured by the involvement of additional sources, together with which the images are used to

aerospace mapping.

Types of cartographic products created from images.

The visual, expressive display of terrain in aerospace imagery creates a natural desire to use aerospace imagery in addition to the map, and sometimes instead of it. This led to the creation of a new type of cartographic product based on many images - photo maps, which are aerospace images transformed into a cartographic projection, usually equipped with elements of a mathematical basis and sometimes having a minimal cartographic load. Medium-scale photo maps are created in the cut-up and nomenclature of survey-topographic and general geographical maps. Numerous* photographic maps of individual countries and continents have also been compiled. A set of photographic maps for the entire world, created from PNHRR/NOAA survey photographs, is contained in the Millennium World Atlas (2001).

Topographic maps. Topographical knowledge of the world, even in our time, remains far from complete. Space images now represent a real basis for topographic mapping. Sometimes they are the only possible survey materials for hard-to-reach high-mountain, desert, and wetlands, which are not only impassable, but also difficult for aerial survey work.

The creation of topographic maps from satellite images is now focused on the use of digital technologies and computer systems.

Update maps. Repeated aerospace surveys provide good materials for regular updating of topographic maps, which is a necessary type of cartographic work. Previously, the update process took many years because it started with large-scale maps; Now you can simultaneously update maps of the entire scale range.

Thematic maps. The resolution of most modern satellite images in the first tens of meters corresponds to the dimension of most objects on the earth's surface studied by geographers. This makes images obtained from resource mapping satellites valuable material for thematic mapping. For the territory of our country, cosmophotogeological and cosmophototectonic maps have been created on scales of 1:10 000 000, 1:5 000 000, 1:2 500 000, containing fundamentally new data on the structure of the earth’s crust, mainly on linear discontinuous and ring structures. State geological maps of scales 1:200,000 (2nd edition) and 1:1,000,000 (3rd edition) are compiled using space information. For this purpose, a so-called “factual remote basis” (or cosmophoto basis) is created, which is a set of photo maps of appropriate scales, created from images of different types, counting on the complementarity of the information extracted from them. Thanks to the use of satellite images, it became possible to complete a multi-sheet soil map of the country at a scale of 1:1,000,000 for the northern and eastern regions and to create a soil map of Russia at a scale of 1:2,500,000.

Based on satellite images at the end of the 20th century. a series of maps on overview scales were created under the program of the Integrated Cartographic Inventory of Natural Resources (CCIPR) for a number of the most important economic regions of Russia: Stavropol, Tver region, Kalmykia, Baikal region, South Yakutia, as well as for Tajikistan, Uzbekistan, Kyrgyzstan, Mongolia.

Abroad, with the advent of space images, a new type of mapping of land cover and land use has become widespread. Such cards are mostly

Headquarters 1:250 LLCs are established in many US states. Overview of global mapping of land covers at the beginning of the 90s. XX century carried out according to AVHRR/M2/L4 data and at the turn of the millennium according to Vegetation/SPOT data. Satellite images are also used in other large thematic mapping projects, for example to create a map of Canadian forests. Global maps of the state of the atmosphere, ocean and many others, characterizing the Earth as a system and its changes, are varied in content.

Aerospace images in GIS. Geographic information systems (GIS) have found the widest application in modern scientific research and practical activities. Along with statistical and cartographic information, they use aerospace images. Imagery is particularly valuable for GIS due to a number of its properties.

The integrated display of natural-territorial systems and their economic use determines the use of images in various thematic areas of research and for studying the interrelations of various objects. Deciphering images allows you to create many sections of information, such as geology, relief, soils, vegetation, economy, and settlement.

The efficiency of obtaining information and its “freshness” ensure the use of images for the rapid identification and assessment of changes occurring on the earth’s surface - updating existing GIS layers, maintaining them at the modern level, and updating information.

A clear time reference of the data and the possibility of using photographs taken at different times and different dates make them an indispensable material for studying the dynamics of nature and the economy.

These properties determine two main directions for using aerospace images in creating GIS. Firstly, they represent a source of primary information when creating thematic layers in a GIS database, especially for hard-to-reach and unsurveyed areas. Secondly, it is an independent element of the database, designed to solve such important problems as studying the interrelations of various geographical objects and phenomena, and studying their dynamics.

The inclusion of aerospace information in geographic information systems imposes its own requirements on the software and system structure, and therefore a special

type of integrated GIS.