Planet Earth: unique in the entire Universe. Study Topic: “Earth in the Universe Links and Notes”
PRACTICAL WORK No. 1, 2
Topic: Earth in the Universe.
Tasks: continue to form an idea of the Universe (origin, composition); characterize the composition of the solar system; Compare terrestrial planets and giant planets.
Equipment: world atlas, diagram “Solar System”, diagram “Structure of the Sun”, pencils.
Progress
Theoretical block
1. What is the Universe? What is its origin?
2. Tell us about the composition of the Universe. When answering, you can use the content of Figures 1, 2, 3.
3. Describe the Solar System (origin, composition). When answering, you can use the content of Figures 2, 3.
4. What do you know about the origin of the solar system?
Practical block
1. Make a comparative description of the planets by filling out the following table.
Comparative characteristics of terrestrial planets and giant planets
When filling out the table, you can use the contents of Figure 4 and Tables 1, 2.
2. Analyze the contents of the completed table and formulate generalizations. Write your answers in your notebook.
Leading block
Prepare the following theoretical material (see below).
1. Axial rotation of the Earth.
2. Orbital (annual) rotation of the Earth around the Sun.
3. Movement of the Earth-Moon system.
Figure 1. Spiral shape of the Galaxy (Shubaev, 1977)
Figure 2. Planets of the Solar System:
1 – Mercury, 2 – Venus, 3 – Earth, 4 – Mars, 5 – Jupiter, 6 – Saturn, 7 – Uranus, 8 – Neptune, 9 – Pluto (Shubaev, 1977)
Figure 3. Comparative values of the Sun and planets (Shubaev, 1977)
Figure 4. Direction and inclination of the rotation axes of the planets of the Solar System (Seliverstov, Bobkov, 2004)
Table 1. Some physical parameters of the planets of the Solar System (Seliverstov, Bobkov, 2004)
Table 2. Chemical composition of the Sun and terrestrial planets, % (Marakushev, 1999)
PRACTICAL WORK No. 3, 4
Topic: Earth in the Universe.
Tasks: continue to form an idea of the Universe (origin, composition); characterize the axial and orbital rotation of the Earth; consider the Earth-Moon motion system.
Equipment: physical map of the world, “Solar System” diagram, “Eclipse” diagram, pencils.
Progress
Theoretical block
Formulate answers to the following questions and tasks.
1. Tell us about the axial rotation of the Earth and the consequences of such rotation. When answering, use the physical map of the world and the pictures in the guidelines.
2. Describe the orbital (annual) rotation of the Earth around the Sun. When answering, use the physical map of the world and Figure 1, 2 in the guidelines.
3. Why is the Moon a satellite of the Earth? Describe the motion of the Earth–Moon system. When answering, use the “Solar System”, “Eclipse” diagrams and Figures 3, 4 in the guidelines.
Practical block
1. Based on the analysis of Figure 2, explain the features of the distribution of solar rays on the Earth’s surface on the day of the winter solstice.
Draw the position of the Earth in relation to the Sun on the day of the summer solstice, on the days of the equinoxes. Use the globe when completing the task.
2. Based on the analysis of Figure 3, explain the changing phases of the Moon. What phase was the Moon in this night (will it be next night)? Record your observations in your workbook.
3. Based on your analysis of Figure 4, explain the causes of solar and lunar eclipses. It is recommended to draw the picture in a workbook. Write an explanation next to it.
Control block
Find the correct answer to the following questions in the suggested assignment options. Write your answer using a combination of numbers and letters.
1. Where is our Sun located in the Galaxy:
A) is the center of the Galaxy;
B) located in the galactic core;
C) located in the main plane of the Galaxy's disk, but not in the center, but closer to the edge?
2. In what orbits do the planets move around the Sun:
A) in circles;
B) along ellipses close to circles;
C) by servitude?
3. In what direction do the planets move in their orbits:
A) all planets move around the Sun in the same direction, like the Earth (in a straight line).
B) all planets move around the Sun in a forward direction, except Venus and Uranus?
4. What bodies, besides the Sun, are included in the Solar System: a) comets; b) stars; c) planets; d) meteoroids; e) satellites of the planets; f) asteroids; g) artificial earth satellites.
5. In what direction do the planets of the Solar System rotate around their own axis: A) all planets rotate around their axis in the direction of rotation around the Sun;
B) all planets, except Venus and Uranus, rotate around an axis in the direction of rotation around the Sun?
A) celestial pole;
7. If, in the process of moving around the Earth, the Moon finds itself in the sky between the Earth and the Sun, then:
A) we see the Moon as a narrow crescent;
B) we see the full disk of the Moon in the sky;
C) we don’t see the Moon at all.
8. If the crescent of the Moon is convex to the right, then:
A) The moon is growing (the moon is “young”);
B) The moon is waning (the Moon is “old”).
9. Lunar eclipses can only occur during:
A) new moon;
B) first quarter;
B) full moon;
D) last quarter.
PRACTICAL WORK No. 5, 6
Topic: Earth as a planet. Determination of geographic coordinates of a point and point by geographic coordinates.
Tasks: continue to develop an idea of the Earth as a planet; systematize and generalize knowledge about geographic coordinates; improve the ability to determine geographic coordinates of points and points by geographic coordinates.
Equipment: physical map of the world, atlases, contour maps, pencils.
Progress
Practical block
Complete the following tasks.
1. On an outline map of the hemispheres, mark the following: equator, northern tropic (Tropic of Cancer), southern tropic (Tropic of Capricorn), northern arctic circle, southern arctic circle. Indicate their position in degrees. Record the data on a contour map.
2. On the contour map of the hemispheres, label the Greenwich (prime or prime) meridian, the date line. Mark the northern and southern hemispheres (relative to the equator), western and eastern hemispheres (relative to the Greenwich meridian).
3. In which of the indicated hemispheres will the following settlements be located - Moscow, New York, Brasilia, Sydney, Morocco, Alaska Peninsula, Society Islands? What will be their latitude and longitude?
Note. The latitude and longitude of points located between the parallels and meridians marked on the map are determined by interpolation. Latitude is northern and southern (N and S), longitude is western and eastern (W and E).
4. According to atlases, determine the coordinates of the following geographical objects: Paris, Cairo, Barnaul, Rio de Janeiro, Delhi, Melbourne, Vlk. Kilimanjaro, Delhi, Magadan, Cape Prince of Wales. At the same time, put all these objects on a contour map, and write down the answers in your workbook.
5. Using the indicated coordinates, determine the names of geographical objects: 1) 29◦ N. w., 89◦w. d.; 2) 14◦ s. w., 13◦w. d.; 3) 2◦ S. w., 78◦w. d.; 4) 32◦ S. w., 19◦ e. d.
6٭. Find cities using geographic coordinates:
1) 56◦ 13" N, 43◦ 49" E. d.
2) 40◦ 25" N, 3◦ 41" W. d.
3) 0◦ 15" S. 78◦ 30" W. d.
4) 33◦ 56" S. 18◦ 25" E. d.
PRACTICAL WORK No. 7, 8, 9
Topic: Earth as a planet. Working with geographical nomenclature.
Tasks: continue to develop an idea of the Earth as a planet; continue to develop the ability to work with geographic nomenclature (searching in geographic atlas maps, drawing on a contour map); the ability to determine the location of marked geographic objects on a map.
Equipment:
Progress
Practical block
Complete the following tasks.
1. On the contour map of individual continents, place the geographical objects indicated in the nomenclature list. Search for these objects in a geographic atlas (using the index of geographic objects and individual maps). When drawing an object on a map, the following recommendations must be observed: 1) make all inscriptions in block letters; 2) water bodies must be drawn with a blue rod; 3) sushi objects must be drawn with a black rod or a simple pencil.
Bays : Venezuelan, Darien, Panama, Guayaquil, Bahia Grande, San Jorge, San Matias, Bahia Blanca, La Plata.
Straits : Magellan, Drake, Falkland.
Islands: Leeward, Galapogos, Tierra del Fuego, Falklands, Trinidad, Tobago.
Capes : Gallinas, Parinhas, Froward, Horn, Cabo Branco.
: Guiana Highlands, Brazilian Highlands, Andes, Caribbean Andes, Patagonia,
Plains, lowlands : Orinoco Lowland, Amazon Lowland, Gran Chaco, La Plata Lowland.
Rivers : Amazon, Marañon, Rio Negro, Ucayali, Purus, Madeira, Orinoco, San Francisco, Parana.
Lakes : Maracaibo, Titicaca, Poopo.
Africa
Seas : Red.
Bays : Sidra, Biafra, Gabes, Aden, Guinea, Benin.
Straits : Gibraltar, Bab El Mandeb, Mozambique.
Islands : Madeira, Ascension, Zanzibar, Canary, St. Helena, Cape Verde, Comoros, Mascarene, Seychelles, Socotra, Madagascar.
Peninsulas : Somalia.
Capes: El Abyad, Almadi, Needles, Good Hope, Ras Hafun.
Mountains, highlands, plateaus : Atlas Mountains, Ahaggar, Tibesti, Ethiopian Highlands (Ras Dashan), Kenya, Kilimanjaro, Kalahari, Drakensberg Mountains, Cape Mountains.
lowland, Mozambican lowland, Kalahari.
Rivers : Nile, White Nile, Blue Nile, Congo, Kasai, Niger, Senegal, Zambezi, Limpopo, Orange.
Lakes : Chad, Tana, Rudolph, Tanganyika, Nyasa, Victoria.
Australia.
Seas : Arafura, Timor, Tasmanovo, Coral.
Bays : Geographa, Great Australian, Spencer, Carpentaria, Joseph Bonaparte.
Straits : Bassov, Torresov.
Islands : Great Barrier Reef, Tasmania, Kangaroo, New Zealand.
Peninsulas : Arnhem Land, Ayr, Cape York, York.
Capes : Steep Point, South East, Byron, York.
Mountains, hills, plateaus : Great Artesian Basin, Great Dividing Range, Australian Alps (Kosciuszko).
Plains : Nullarbor.
Rivers : Flinders, Eyre Creek, Cooper's Creek, Murray (Murree), Darling.
Lakes : Ayr, Frome, Torrens.
Oceania.
Melanesia.
Islands : New Guinea, New Caledonia, New Hebrides, Fiji, Solomon.
Micronesia.
Islands : Caroline, Mariana, Guam, Nauru, Marshall, Gilbert.
Polynesia.
Islands : Hawaiian, Tongan, Kuka, Samoan, Line, Marquesan, Societies, Tuamotu, Easter.
Antarctica and Antarctica.
Seas : Wedell, Bellingshausen, Amundsen, Ross.
Islands : South Georgia, South Sandwich Islands, Alexander Land, Peter I Island, South Orkney Islands, South Shetland Islands.
Peninsulas : Antarctic.
Sea currents.
Warm currents (go from low to high latitudes) : Kuroshio, North Pacific, Alaskan, East Australian, Aguls, Mozambique, Brazilian, Guiana, Caribbean, Antilles, Norwegian, Irminger, Spitsbergen, West Greenland, North Cape, New Zealand, Gulf Stream, North Atlantic.
Cold currents (directed from high to low latitudes) :
East Greenland, Labrador, Peruvian, Cape Horn, Falkland, Benguela, Kamchatka, California.
Neutral currents (characterized by the fact that their waters do not differ in temperature from the surrounding waters) : North Trade Wind, South Trade Wind, Equatorial Countercurrent, Monsoon Current.
PRACTICAL WORK No. 10
Topic: Physiographic overview of continents
Tasks: continue to develop an idea of the Earth as a planet; continue to develop the ability to work with geographical maps (thematic, general geographical); compile a description of the continents as objects of the geographical envelope; continue to develop the ability to determine the location of geographical objects on the map.
Equipment: physical map of the world, geography atlases, contour maps, pencils.
Progress
Practical block
1. How does the concept of “continent” differ from “part of the world”?
2. Formulate a definition of the concept “continent”. What continents do you know?
Table - 1 Physiographic characteristics of the continents
Characteristics of the continent | CONTINUES |
|||||
North America | South America | Australia and Oceania | Antarctica |
|||
1.Physical-geographical location (extreme points of the continents, size of the territory, nature of the coastline). | ||||||
2. Tectonic structure and relief. Minerals. | ||||||
Climate (climatic zones and climate types). Features of circulation. | ||||||
Inland waters (presence of areas of external and internal flow, large rivers, lakes) | ||||||
Natural areas | ||||||
Features of the continent's nature |
4. After completing the work, identify similarities and differences in the nature of the continents.
Control block
1. Which degree network lines cross Africa?
2. By what conventional line can Africa be divided into “low” and “high”?
3. Why is Africa called the “hottest continent”?
4. Why is Australia called the “dryest continent”?
5. Why is Australia called the “calmest continent”?
6. Are all the islands of the Pacific Ocean part of Oceania? Give examples to support your answer.
7. Why is South America called the “wettest continent”?
8. Why is Antarctica called the “highest continent”?
9. Where is the “pole of cold” of the northern and southern hemispheres? What is the reason for this situation?
10. Why are the Cordilleras located in the west of the continent?
11. Which territories of Eurasia have the most favorable living conditions for the population? Why?
PRACTICAL WORK No. 11
Topic: Physiographic overview of the oceans
Tasks: continue to develop an idea of the Earth as a planet; continue to develop the ability to work with geographical maps (thematic, general geographical); compile a description of the oceans as objects of the geographical envelope; continue to develop the ability to determine the location of geographical objects on the map.
Equipment: physical map of the world, geography atlases, contour maps, pencils.
Progress
Practical block
Answer the following questions and tasks.
1. Formulate a definition of the concept “ocean”. What oceans do you know?
2. List the characteristic features of the nature of each of the oceans. Justify your answer.
3. Using the atlas maps, fill out the following table.
Table - 1 Physiographic characteristics of the oceans
Characteristics of the ocean | ||||
Atlantic | Indian | Arctic |
||
1.Physico-geographical location | ||||
2. Tectonic structure and bottom topography. | ||||
3.Climate (position in climatic zones, prevailing winds) | ||||
4.Currents (cold, warm, neutral) | ||||
5.Organic world | ||||
6.Natural belts | ||||
7.Environmental problems of the ocean |
Control block
1. Which seas are named after famous people? Why?
2. Which seas of the World Ocean can be classified as: marginal, Mediterranean, internal, interisland? Why?
3. What do you understand by the “Pacific Ring of Fire”?
4. Name the currents that are analogues of the following:
Gulf Stream, Alaskan, Brazilian, Peruvian, Labrador, California. Note: analogue currents must be searched at the same latitudes in the waters of another ocean.
5. Which part of the world's oceans is called the "Roaring Forties"? Why?
6. At what latitudes and why are “ocean deserts” formed?
Slide captions:
Asteroids
«
star-like"
Add
9. The most important difference between the Earth and other planets is...
10. The solar system includes:
A) planets
B) Satellites of the planets
IN) _______________
G)________________
Universe
This is the entire existing world. It is infinite in time and space.
Solar system
Mercury
Year – 88 Earth days
Rotation around its axis in 58.7 Earth days
Distance 58 million km
Venus
Year – 225 Earth days
Rotation around its axis in 243 Earth days
Distance 108 million km
Earth
Year – 365 Earth days
Revolution around its axis in 1 Earth day
Distance 150 million km
Mars
Year – 687 Earth days
Revolution around its axis in 24 hours
Distance 228 million km
Jupiter (moon - Ganymede)
Year – 12 earth years
Rotation around its axis in 10 hours
Distance 778 million km
Saturn
Year – 30 Earth years
Rotation around its axis in 10 hours 34 minutes
Distance 1426 million km
Uranus
Year – 84 Earth years
Rotation around its axis in 17 hours 12 minutes
Distance 2860 million km
Neptune
Year –165 Earth years
Rotation around its axis in 16 hours 6 minutes
Distance 4500 million km
Pluto
Year – 250 Earth years
Revolution around its axis in 6 Earth days 9 hours
Distance 5906 million km
Geographical dictation
5
. The smallest planet is Venus
6. Saturn is one of the giant planets
7. Mercury has a hydrosphere
8.The Andromeda Galaxy is closest to the earth
Earth in the Universe
Earth and space
Movement of the Earth around the Sun
Navigation stars
Navigation stars –
stars
, with the help of which in aviation, navigation and astronautics they determine the location and course of a ship.
For orientation in the Northern Hemisphere of the Earth, 18 navigation stars are used. In the northern celestial hemisphere it is Polar,
Vega
, Chapel,
Alioth
etc.
To these stars are added 5 stars of the southern hemisphere of the sky: Sirius, Rigel,
Spica
, Antares and
Fomalgayut
.
Geographical dictation
1. The galaxy to which the Earth belongs is called the Milky Way
2. Mars is one of the giant planets
3. Mercury is closest to the Sun
4. The largest planet is Jupiter
Magellanic Clouds
Andromeda's nebula
The movement of the Earth around its axis
66.5°
Comet
Resources:
http://images.yandex.ru/yandsearch?p=1&text=%D0%B7%D0%B5%D0%BC%D0%BB%D1%8F%20%D0%BF%D0%BB%D0%B0 %D0%BD%D0%B5%D1%82%D0%B0&img_url=bigjournal.net%2Fwp-content%2Fuploads%2F2012%2F03%2F%D1%84%D0%BE%D1%82%D0%BE-% D0%B7%D0%B5%D0%BC%D0%BB%D0%B8-%D1%81%D0%BE-%D1%81%D0%BF%D1%83%D1%82%D0%BD%
D0%B8%D0%BA%D0%B0-45.jpg&pos=35&rpt=simage
Earth
http://images.yandex.ru/yandsearch?text=%D0%BC%D0%B0%D1%80%D1%81%20%D0%BF%D0%BB%D0%B0%D0%BD%D0 %B5%D1%82%D0%B0&img_url=www.milkywaygalaxy.ru%2Fimages%2Fmars%20foto.jpg&pos=1&rpt=simage
Mars
http://images.yandex.ru/yandsearch?p=1&text=%D1%8E%D0%BF%D0%B8%D1%82%D0%B5%D1%80%20%D0%BF%D0%BB %D0%B0%D0%BD%D0%B5%D1%82%D0%B0%20%D1%81%D0%BF%D1%83%D1%82%D0%BD%D0%B8%D0%BA %D0%B8&img_url=www.cbsnews.com%2Fi%2Ftim%2F2010%2F11%2F12%2Fvoy5_1_540x405.jpg&pos=59&rpt=simage
Jupiter
http://images.yandex.ru/yandsearch?text=%D1%81%D0%B0%D1%82%D1%83%D1%80%D0%BD%20%D0%BF%D0%BB%D0 %B0%D0%BD%D0%B5%D1%82%D0%B0%20%D1%84%D0%BE%D1%82%D0%BE&img_url=sandbox.yoyogames.com%2Fextras%2Fimage%2Fname%2Fsan1 %2F532%2F8532%2Fsaturn.jpg&pos=7&rpt=simage
Saturn
http://images.yandex.ru/yandsearch?text=%D1%83%D1%80%D0%B0%D0%BD%20%D0%BF%D0%BB%D0%B0%D0%BD%D0 %B5%D1%82%D0%B0%20%D1%84%D0%BE%D1%82%D0%BE&img_url=cs10383.userapi.com%2Fu6851945%2F-6%2Fx_6ed35aa2.jpg&pos=1&rpt=simage
Uranus
http://astrohome-kherson.narod.ru/images/slice_4/asteroidu.htm
solar system
http://images.yandex.ru/yandsearch?text=%D0%BA%D0%BE%D0%BC%D0%B5%D1%82%D0%B0%20%D0%B3%D0%B0%D0 %BB%D0%BB%D0%B5%D1%8F&img_url=kartcent.ru%2Fwp-content%2Fuploads%2F2011%2F12%2Fkometa-halley-12.03.86.jpg&pos=1&rpt=simage
comet
http://images.yandex.ru/yandsearch?text=%D0%BF%D0%BB%D1%83%D1%82%D0%BE%D0%BD%20%D0%BF%D0%BB%D0 %B0%D0%BD%D0%B5%D1%82%D0%B0&img_url=y-tver.com%2Fusers%2F100%2Fcolor1324991656.jpg&pos=1&rpt=simage
http://ru.wikipedia.org/wiki/%D1%EE%EB%ED%E5%F7%ED%E0%FF_%F1%E8%F1%F2%E5%EC%E0
solar system
Milky Way
Huge,
gravitationally
connected system containing about 200 billion stars thousands of giant clouds of gas and dust, clusters and nebulae
m
eteors
1 option
Option 2
11. Navigation stars in the Northern Hemisphere are ______
12. What common features do the terrestrial planets have?
13. The Universe is
11. Navigation stars in the Southern Hemisphere are ______
12.What common features do the planets have?
–giants
13. The solar system is
To ancient people, the Earth seemed huge. Therefore, ancient philosophers, thinking about the structure of the Universe, placed the Earth at its center. All celestial bodies, they believed, revolve around the Earth.
In the modern world, when there is aviation and spaceships, the idea that our planet is not at all the center of the universe does not seem seditious to anyone.
However, this idea was first expressed in the 3rd century BC. Aristarchus of Samos. Unfortunately, almost all the works of this ancient Greek scientist have been lost and are known to us only in the retelling of his contemporary Archimedes. Therefore, the assumption that the Earth revolves around the Sun (and not the Sun around the Earth) is usually associated with the name of the Polish astronomer Nicolaus Copernicus, who lived in the 15th-16th centuries. Copernicus arranged the planets of the solar system known to him as follows: Mercury, Venus, Earth, Mars, Jupiter and Saturn revolve around the Sun, and the Moon revolves around the Earth. But further behind Saturn, Copernicus placed the “sphere of fixed stars” - a kind of wall enclosing the Universe. But Copernicus could not guess what was behind it - he did not have enough data for this. One should not accuse Copernicus of myopia, because the telescope that brought distant space closer to us was first used by Galileo only a hundred years later.
Modern science knows that our Sun is one of countless stars in the Universe, not the largest, not the brightest, not the hottest, moreover, the Sun is located far from the center of our Galaxy - a giant cluster of stars, which includes the Sun. And we are lucky in this. After all, otherwise such streams of cosmic rays would fall on the Earth that life would hardly arise on it. 9 large planets revolve around the Sun, minor planets - asteroids, comets and very small “pebbles” - meteoroids. All this together forms the solar system.
Earth is one of 9 planets. Not the biggest, but not the smallest, not the closest to the Sun, but not the farthest. The largest planet is Jupiter. Its mass is 318 times that of Earth. But Jupiter has no solid surface to walk on. The farthest planet from the Sun, Pluto, is almost 40 times farther from the Sun than Earth. Its surface is hard, it would be easy to walk on it - Pluto is smaller than the Moon and attracts weakly towards itself. It’s just cold there: the temperature is 200-240°C below the freezing point of water. Under such conditions, not only water, but also most gases become solid. But on Venus, our closest neighbor, the temperature is above +450°C. It turns out that the Earth is the only planet in the Universe so far suitable for life.
From the Earth to the Sun there are about 150 million km. Is it a lot or a little? Let's compare this distance with the sizes of the Sun and Earth. The diameter of the Sun is about 100 times smaller, and the diameter of the Earth is 10,000 times smaller. This means that if we depict the Sun as a circle with a diameter of 1 cm (the size of a 1 ruble coin), then we will have to draw the Earth at a distance of 1 m (at the other end of a large table), and it will be barely noticeable accurate.
Our Earth is part of the Universe. What place does it occupy among other world bodies and what is a person like in world space?
Earth is a celestial body
Earth is a large celestial body. Its volume is approximately 1083 billion cubic kilometers, its surface is about 510 million square kilometers and its weight is about 6 thousand trillion tons. The Earth is a large celestial body. But The Earth, in turn, is very small compared to the Sun, which is 1 million 300 thousand times larger than the globe. However, it turns out that the Sun is not so big. Among the representatives of the world's bodies there are stars larger than the Sun. So, for example, in the constellation Scorpio there is giant star Antares, which is almost 3.5 million times larger in volume than the Sun. But even such giants are not “crowded” in the Universe; they move freely and at enormous speeds (20 – 80 kilometers per second) throughout the Universe, which is limitless in space and time. What is the Earth like in the infinite Universe? Just an insignificant speck of dust! But, it, along with other bodies of the solar system, participates in the rapid flight of our radiant Sun, among the hosts of stars in the Galaxy (more details:). However, all “we” are located on this insignificant speck of dust – all people and the entire animal and plant world. As if on a colossal interplanetary ship, we constantly travel in cosmic space and, together with the Sun, we rush further and further!Man in the Universe
What a place man in the universe? It is so insignificantly small that any comparisons or scales lose all meaning here. But we must say that the human mind subjugates the forces of nature and even penetrates the vast expanses of the Universe.
Man in the vast expanses of the Universe. Man crosses seas and oceans, explores their watery depths; he conquered the ocean of air and, like an eagle, soars in the blue expanses of the sky; he dug deep tunnels through the mountains; He mentally penetrates even into the deep bowels of our Earth; he gradually conquers the entire Earth and its water and atmospheric shells, (more details:). The inquisitive mind of man went even further: he penetrated into the “life” of invisible molecules and atoms, just as he penetrated into the “life” of giant stars. He tirelessly reveals the secrets of nature one after another, and wider and wider horizons open up to him. Man left the narrow arena called Earth, and space flights throughout the Universe became available to him. Throughout the history of science, the interests of geoscience have included developing ideas about the world around humans - planet Earth, the solar system, the Universe. The first mathematically substantiated model of the universe was the geocentric system of C. Ptolemy (165-87 BC), which correctly for that time reflected the part of the world accessible to direct observation. Only 1500 years later, the heliocentric model of the solar system of N. Copernicus (1473-1543) was established.
Advances in physical theory and astronomy at the end of the 19th century. and the advent of the first optical telescopes led to the creation of ideas about an unchanging Universe. The development of the theory of relativity and its application to the solution of cosmological paradoxes (gravitational, photometric) created a relativistic theory of the Universe, which was initially presented by A. Einstein as a static model. In 1922-1924 gt. A.A. Friedman obtained solutions to the equations of the general theory of relativity for matter uniformly filling all space (model of a homogeneous isotropic Universe), which showed the non-stationary nature of the Universe - it must expand or contract. In 1929, E. Hubble discovered the expansion of the Universe, refuting the idea of its inviolability. The theoretical results of A.A. Friedman and E. Hubble made it possible to introduce the concept of “beginning” into the evolution of the Universe and explain its structure.
In 1946-1948. G. Gamow developed the theory of the “hot” Universe, according to which at the beginning of evolution the matter of the Universe had a temperature and density that were unattainable experimentally. In 1965, relict microwave background radiation was discovered, which initially had a very high temperature, which experimentally confirmed G. Gamow’s theory.
This is how our ideas about the world expanded in spatial and temporal terms. If for a long time the Universe was considered as an environment that included celestial bodies of various ranks, then according to modern ideas, the Universe is an ordered system developing unidirectionally. Along with this, the assumption arose that the Universe does not necessarily exhaust the concept of the material world and perhaps there are other Universes where the known laws of the universe do not necessarily apply.
Universe
Universe- this is the material world around us, limitless in time and space. The boundaries of the Universe will most likely expand as new opportunities for direct observation emerge, i.e. they are relative for each moment in time.
The Universe is one of the concrete scientific objects of experimental research. The fundamental laws of natural science are assumed to be true throughout the universe.
State of the Universe. The Universe is a non-stationary object, the state of which depends on time. According to the prevailing theory, the Universe is currently expanding: most galaxies (with the exception of those closest to ours) are moving away from us and relative to each other. The farther away the galaxy - the source of radiation - is located, the greater the speed of retreat (scattering). This dependence is described by the Hubble equation:
Where v- removal speed, km/s; R- distance to the galaxy, St. year; N - proportionality coefficient, or Hubble constant, H = 15×10 -6 km/(s×sa. year). It has been established that the acceleration speed increases.
One of the proofs of the expansion of the Universe is the “red shift of spectral lines” (Doppler effect): spectral absorption lines in objects moving away from the observer are always shifted towards long (red) waves of the spectrum, and approaching ones - towards short (blue).
Spectral absorption lines from all galaxies are inherently redshifted, which means expansion occurs.
Density of matter in the Universe. The distribution of matter density in individual parts of the Universe differs by more than 30 orders of magnitude. The highest density, if you do not take into account the microcosm (for example, the atomic nucleus), is inherent in neutron stars (about 10 14 g/cm 3), the lowest (10 -24 g/cm 3) - in the Galaxy as a whole. According to F.Yu. Siegel, the normal density of interstellar matter in terms of hydrogen atoms is one molecule (2 atoms) per 10 cm 3, in dense clouds - nebulae it reaches several thousand molecules. If the concentration exceeds 20 hydrogen atoms per 1 cm 3, then the process of convergence begins, developing into accretion (sticking together).
Material composition. Of the total mass of matter in the Universe, only about 1/10 is visible (luminous), the remaining 9/10 is invisible (non-luminous) matter. Visible matter, the composition of which can be confidently judged by the nature of the emission spectrum, is represented mainly by hydrogen (80-70%) and helium (20-30%). There are so few other chemical elements in the luminous mass of matter that they can be neglected. There is no significant amount of antimatter found in the Universe, with the exception of a small fraction of antiprotons in cosmic rays.
The universe is filled with electromagnetic radiation, which is called relict, those. left over from the early stages of the evolution of the Universe.
Homogeneity, isotropy and structure. On a global scale, the Universe is considered isotropic And homogeneous. A sign of isotropy, i.e. The independence of the properties of objects from the direction in space is the uniformity of the distribution of relict radiation. The most accurate modern measurements have not detected deviations in the intensity of this radiation in different directions and depending on the time of day, which at the same time indicates the great homogeneity of the Universe.
Another feature of the Universe is heterogeneity And structure(discreteness) on a small scale. On a global scale of hundreds of megaparsecs, the matter of the Universe can be considered as a homogeneous continuous medium, the particles of which are galaxies and even clusters of galaxies. A more detailed examination reveals the structured nature of the Universe. The structural elements of the Universe are cosmic bodies, primarily stars, forming stellar systems of different ranks: galaxy- galaxy cluster- Metagalaxy, They are characterized by localization in space, movement around a common center, a certain morphology and hierarchy.
The Milky Way Galaxy consists of 10 11 stars and the interstellar medium. It belongs to spiral systems that have a plane of symmetry (the plane of the disk) and an axis of symmetry (the axis of rotation). The oblateness of the Galaxy's disk, observed visually, indicates a significant speed of its rotation around its axis. The absolute linear speed of its objects is constant and equal to 220-250 km/s (it is possible that it increases for objects very distant from the center). The period of rotation of the Sun around the center of the Galaxy is 160-200 million years (on average 180 million years) and is called galactic year.
Evolution of the Universe. In accordance with the model of the expanding Universe, developed by A.A. Friedman on the basis of A. Einstein’s general theory of relativity, it has been established that:
1) at the beginning of evolution, the Universe experienced a state of cosmological singularity, when the density of its matter was equal to infinity and the temperature exceeded 10 28 K (with a density of over 10 93 g/cm 3 the matter has unexplored quantum properties of space-time and gravity);
2) a substance in a singular state underwent a sudden expansion, which can be compared to an explosion (“Big Bang”);
3) under conditions of nonstationarity of the expanding Universe, the density and temperature of matter decrease with time, i.e. in the process of evolution;
4) at a temperature of the order of 10 9 K, nucleosynthesis took place, as a result of which chemical differentiation of matter occurred and the chemical structure of the Universe arose;
5) based on this, the Universe could not exist forever and its age is determined from 13 to 18 billion years.
solar system
Solar system - this is the Sun and a set of celestial bodies: 9 planets and their satellites (as of 2002 their number was 100), many asteroids, comets and meteors that revolve around the Sun or enter (like comets) into the Solar System. Basic information about the objects of the Solar system is contained in Fig. 3.1 and table. 3.1.
Table 3.1. Some physical parameters of the planets of the solar system
| Solar System Object | Distance from the Sun | radius, km | number of earth radii | weight, 10 23 kg | mass relative to Earth | average density, g/cm 3 | orbital period, number of Earth days | period of rotation around its axis | number of satellites (moons) | albedo | acceleration of gravity at the equator, m/s 2 | speed of separation from the planet's gravity, m/s | presence and composition of the atmosphere, % | average surface temperature, °C | |
| million km | a.e. | ||||||||||||||
| Sun | - | 695 400 | 1.989×10 7 | 332,80 | 1,41 | 25-36 | 9 | - | 618,0 | Absent | |||||
| Mercury | 57,9 | 0,39 | 0,38 | 3,30 | 0,05 | 5,43 | 59 days | 0,11 | 3,70 | 4,4 | Absent | ||||
| Venus | 108,2 | 0,72 | 0,95 | 48,68 | 0,89 | 5,25 | 243 days | 0,65 | 8,87 | 10,4 | CO 2, N 2, H 2 O | ||||
| Earth | 149,6 | 1,0 | 1,0 | 59,74 | 1,0 | 5,52 | 365,26 | 23 h 56 min 4s | 0,37 | 9,78 | 11,2 | N 2, O 2, CO 2, Ar, H 2 O | |||
| Moon | 1,0 | 0,27 | 0,74 | 0,0123 | 3,34 | 29,5 | 27 h 32 min | - | 0,12 | 1,63 | 2,4 | Very dressed up | -20 | ||
| Mars | 227,9 | 1,5 | 0,53 | 6,42 | 0,11 | 3,95 | 24 h 37 min 23 s | 0,15 | 3,69 | 5,0 | CO 2 (95.3), N 2 (2.7), Ar (1.6), O 2 (0.15), H 2 O (0.03) | -53 | |||
| Jupiter | 778,3 | 5,2 | 18986,0 | 1,33 | 11.86 years | 9 h 30 min 30 s | 0,52 | 23,12 | 59,5 | N (77), Not (23) | -128 | ||||
| Saturn | 1429,4 | 9,5 | 5684,6 | 0,69 | 29.46 years | 10 hours 14 minutes | 0,47 | 8,96 | 35,5 | N, Not | -170 | ||||
| Uranus | 2871,0 | 19,2 | 25 362 | 868,3 | 1,29 | 84.07 years | 11 h3 | 0,51 | 8,69 | 21,3 | N (83), He (15), CH 4 (2) | -143 | |||
| Neptune | 4504,3 | 30,1 | 24 624 | 1024,3 | 1,64 | 164.8 years | 16h | 0,41 | 11,00 | 23,5 | N, He, CH 4 | -155 | |||
| Pluto | 5913,5 | 39,5 | 0,18 | 0,15 | 0,002 | 2,03 | 247,7 | 6.4 days | 0,30 | 0,66 | 1,3 | N2, CO, NH4 | -210 |
Sun is a hot gas ball, in which about 60 chemical elements were found (Table 3.2). The Sun rotates around its axis in a plane inclined at an angle of 7°15" to the plane of the earth's orbit. The speed of rotation of the surface layers of the Sun is different: at the equator the period of revolution is 25.05 days, at a latitude of 30° - 26.41 days, in the polar regions - 36 days. The source of the Sun's energy is nuclear reactions that convert hydrogen into helium. The amount of hydrogen will ensure the preservation of its luminosity for tens of billions of years. Only one two-billionth of the solar energy reaches the Earth.
The sun has a shell structure (Fig. 3.2). In the center they highlight core with a radius of approximately 1/3 of the sun, a pressure of 250 billion atm, a temperature of more than 15 million K and a density of 1.5 × 10 5 kg/m 3 (150 times the density of water). Almost all of the sun's energy is generated in the core, which is transmitted through radiation zone, where light is repeatedly absorbed by a substance and re-emitted. Above is located convection zone(mixing), in which a substance begins to move due to uneven heat transfer (a process similar to the transfer of energy in a boiling kettle). The visible surface of the Sun is formed by its atmosphere. Its lower part with a thickness of about 300 km, emitting the bulk of the radiation, is called photosphere. This is the "coldest" place on the Sun with temperatures decreasing from 6000 to 4500 K in the upper layers. The photosphere is formed by granules with a diameter of 1000-2000 km, the distance between which is from 300 to 600 km. The granules create a general background for various solar formations - prominences, faculae, spots. Above the photosphere to an altitude of 14 thousand km is located chromosphere. During total lunar eclipses, it is visible as a pink halo surrounding a dark disk. The temperature in the chromosphere increases and in the upper layers reaches several tens of thousands of degrees. The outermost and thinnest part of the solar atmosphere is solar corona- extends over distances of several tens of solar radii. The temperature here exceeds 1 million degrees.
Table 3.2. Chemical composition of the Sun and terrestrial planets, % (according to A. A. Marakushev, 1999)
| Element | Sun | Mercury | Venus | Earth | Mars |
| Si | 34,70 | 16,45 | 33,03 | 31,26 | 36,44 |
| Fe | 30,90 | 63,07 | 30,93 | 34,50 | 24,78 |
| Mg | 27,40 | 15,65 | 31,21 | 29,43 | 34,33 |
| Na | 2,19 | - | - | - | - |
| Al | 1,74 | 0,97 | 2,03 | 1,90 | 2,29 |
| Ca | 1,56 | 0,88 | 1,62 | 1,53 | 1,73 |
| Ni | 0,90 | 2,98 | 1,18 | 1,38 | 0,43 |
Rice. 3.2. Structure of the Sun
Planets The solar system is divided into two groups: internal, or terrestrial planets - Mercury, Venus, Earth, Mars, and external, or giant planets - Jupiter, Saturn, Uranus, Neptune and Pluto. The estimated material composition of the planets is shown in Fig. 3.3.
Terrestrial planets. The inner planets have relatively small sizes, high density and internal differentiation of matter. They are distinguished by an increased concentration of carbon, nitrogen and oxygen, and a lack of hydrogen and helium. Terrestrial planets are characterized by tectonic asymmetry: the structure of the crust of the northern hemispheres of the planets differs from the southern ones.
Mercury - the planet closest to the Sun. Among the planets of the Solar System, it is distinguished by the most elongated elliptical orbit. The temperature on the illuminated side is 325-437°C, on the night side - from -123 to -185°C. The American spacecraft Mariner 10 in 1974 discovered a rarefied atmosphere on Mercury (pressure 10 -11 atm), consisting of helium and hydrogen in a ratio of 50:1. Mercury's magnetic field is 100 times weaker than Earth's, which is largely due to the planet's slow rotation around its axis. The surface of Mercury has much in common with the surface of the Moon, but the continental topography predominates. Along with lunar-like craters of various sizes, scarps that are absent on the Moon are noted - cliffs, 2-3 km high and hundreds and thousands of kilometers long.
Rice. 3.3. The structure and estimated material composition of the planets (according to G.V. Voitkevich): A - earth group: 1, 2, 3 - silicate, metal, metal sulfide substances, respectively; b- giants: 1 - molecular hydrogen; 2 - metallic hydrogen; 3 - water ice; 4 - core composed of stone or iron-stone material
The mass of Mercury is 1/18 of the mass of the Earth. Despite its small size, Mercury has an unusually high density (5.42 g/cm3), close to the density of the Earth. The high density indicates a hot, and likely molten, metallic core, which accounts for about 62% of the planet's mass. The core is surrounded by a silicate shell about 600 km thick. The chemical composition of the surface rocks and subsoil of Mercury can be judged only from indirect data. The reflectivity of the Mercury regolith indicates that it consists of the same rocks that make up the lunar soil.
Venus rotates around its axis even slower (in 244 Earth days) than Mercury, and in the opposite direction, so the Sun on Venus rises in the west and sets in the east. The mass of Venus is 81% of the earth's mass. The weight of objects on Venus is only 10% less than their weight on Earth. It is believed that the planet’s crust is thin (15-20 km) and its main part is represented by silicates, which are replaced at a depth of 3224 km by an iron core. The planet's topography is dissected - mountain ranges up to 8 km high alternate with craters with a diameter of tens of kilometers (maximum up to 160 km) and a depth of up to 0.5 km. Vast leveled spaces are covered with rocky scatterings of sharp-angled debris. A giant linear depression up to 1500 km long and 150 km wide with a depth of up to 2 km was discovered near the equator. Venus does not have a dipole magnetic field, which is explained by its high temperature. On the surface of the planet the temperature is (468+7)°C, and at depth, obviously, 700-800°C.
Venus has a very dense atmosphere. On the surface, the atmospheric pressure is at least 90-100 atm, which corresponds to the pressure of the earth’s seas at a depth of 1000 m. The chemical composition of the atmosphere consists mainly of carbon dioxide with an admixture of nitrogen, water vapor, oxygen, sulfuric acid, hydrogen chloride and hydrogen fluoride. It is believed that the atmosphere of Venus roughly corresponds to the earth’s in the early stages of its formation (3.8-3.3 billion years ago). The cloud layer of the atmosphere extends from a height of 35 km to 70 km. The lower layer of clouds consists of 75-80% sulfuric acid, in addition, hydrofluoric and hydrochloric acids are present. Being 50 million km closer than the Earth to the Sun, Venus receives twice as much heat as our planet - 3.6 cal/(cm 2 × min). This energy is accumulated by the carbon dioxide atmosphere, which causes a huge greenhouse effect and high temperatures of the Venusian surface - hot and, apparently, dry. Cosmic information indicates a peculiar glow of Venus, which is probably explained by the high temperatures of surface rocks.
Venus is characterized by complex cloud dynamics. There are probably powerful polar vortexes and strong winds at an altitude of about 40 km. Near the surface of the planet, the winds are weaker - about 3 m/s (obviously due to the absence of significant differences in surface temperature), which is confirmed by the absence of dust in the landing sites of the Venus station's descent modules. For a long time, the dense atmosphere did not allow us to judge the rocks of the Venusian surface. Analysis of the natural radioactivity of uranium, thorium and potassium isotopes in soils showed results close to those of terrestrial basalts and partially granites. Surface rocks are magnetized.
Mars is located 75 million km farther from the Sun than the Earth, so the Martian day is longer than the Earth's, and the amount of solar energy it receives is 2.3 times less compared to the Earth. The period of rotation around its axis is almost the same as that of the Earth. The inclination of the axis to the orbital plane ensures the change of seasons and the presence of “climatic” zones - a hot equatorial one, two temperate ones and two polar ones. Due to the small amount of incoming solar energy, the contrasts of thermal zones and seasons of the year are less pronounced than on Earth.
The density of the atmosphere of Mars is 130 times less than that of Earth and is only 0.01 atm. The atmosphere contains carbon dioxide, nitrogen, argon, oxygen, and water vapor. Daily temperature fluctuations exceed 100°C: at the equator during the day - about 10-20°C, and at the poles - below -100°C. Large temperature differences are observed between the day and night sides of the planet: from 10-30 to -120°C. At an altitude of about 40 km, Mars is surrounded by an ozone layer. A weak dipole magnetic field has been noted for Mars (at the equator it is 500 times weaker than the Earth's).
The surface of the planet is pitted with numerous craters of volcanic and meteorite origin. The average height difference is 12-14 km, but the huge caldera of the Nix Olympics volcano (Snows of Olympus) rises to 24 km. The diameter of its base is 500 km, and the diameter of the crater is 65 km. Some volcanoes are active. A peculiarity of the planet is the presence of huge tectonic cracks (for example, the Marineris Canyon, 4000 km long and 2000 km wide with a depth of up to 6 km), reminiscent of terrestrial grabens and morphosculptures corresponding to river valleys.
Images of Mars show areas that are light in color (“continental” areas, apparently composed of granites), yellow in color (“marine” areas, apparently composed of basalts) and snow-white in appearance (glacial polar caps). Observations of the polar regions of the planet have established variability in the outlines of ice massifs. According to scientists, the glacial polar caps are composed of frozen carbon dioxide and, possibly, water ice. The reddish color of the surface of Mars is probably due to hematitization and limonitization (iron oxidation) of rocks, which are possible in the presence of water and oxygen. Obviously, they come from the inside when the surface warms up during the day or with gas exhalations that melt the permafrost.
A study of rocks showed the following ratio of chemical elements (%): silica - 13-15, iron oxides - 12-16, calcium - 3-8, aluminum - 2-7, magnesium - 5, sulfur - 3, as well as potassium, titanium , phosphorus, chromium, nickel, vanadium. The composition of the soil on Mars is similar to some terrestrial volcanic rocks, but is enriched in iron compounds and depleted in silica. No organic formations were found on the surface. In the near-surface layers of the planet (from a depth of 50 cm), the soils are bound by permafrost, extending up to 1 km deep. In the depths of the planet, the temperature reaches 800-1500°C. It is assumed that at shallow depths the temperature should be 15-25 ° C, and the water may be in a liquid state. Under these conditions, the simplest living organisms can exist, traces of whose vital activity have not yet been found.
Mars has two satellites - Phobos (27x21x19 km) and Deimos (15x12x11 km), which are obviously fragments of asteroids. The orbit of the first passes 5,000 km from the planet, the second - 20,000 km.
In table Figure 3.2 shows the chemical composition of the terrestrial planets. The table shows that Mercury is characterized by the highest concentrations of iron and nickel and the lowest silicon and magnesium.
Giant planets. Jupiter, Saturn, Uranus and Neptune are noticeably different from the terrestrial planets. In the giant planets, especially those closest to the Sun, the total angular momentum of the Solar system (in Earth units) is concentrated: Neptune - 95, Uranus - 64, Saturn - 294, Jupiter - 725. The distance of these planets from the Sun allowed them to retain a significant amount primary hydrogen and helium lost by the terrestrial planets under the influence of the “solar wind” and due to the insufficiency of their own gravitational forces. Although the density of the substance of the outer planets is small (0.7-1.8 g/cm3), their volumes and masses are enormous.
The largest planet is Jupiter, which is 1300 times larger in volume and more than 318 times larger in mass than Earth. It is followed by Saturn, whose mass is 95 times the mass of the Earth. These planets contain 92.5% of the mass of all planets in the Solar System (71.2% for Jupiter and 21.3% for Saturn). The group of outer planets is completed by two twin giants - Uranus and Neptune. An important feature is the presence of rocky satellites on these planets, which probably indicates their external cosmic origin and is not associated with the differentiation of the substance of the planets themselves, formed by condensations primarily in the gaseous state. Many researchers believe that the central parts of these planets are rocky.
Jupiter with characteristic spots and stripes on the surface that are parallel to the equator and have variable outlines, it is the most accessible planet for exploration. The mass of Jupiter is only two orders of magnitude less than the Sun. The axis is almost perpendicular to the orbital plane.
Jupiter has a powerful atmosphere and a strong magnetic field (10 times stronger than the Earth’s), which determines the presence around the planet of powerful radiation belts of protons and electrons captured by Jupiter’s magnetic field from the “solar wind”. The atmosphere of Jupiter, in addition to molecular hydrogen and helium, contains various impurities (methane, ammonia, carbon monoxide, water vapor, phosphine molecules, hydrogen cyanide, etc.). The presence of these substances may be a consequence of the assimilation of heterogeneous material from Space. The layered hydrogen-helium mass reaches a thickness of 4000 km and, due to the uneven distribution of impurities, forms stripes and spots.
The huge mass of Jupiter suggests the presence of a powerful liquid or semi-liquid core of the asthenospheric type, which can be the source of volcanism. The latter, in all likelihood, explains the existence of the Great Red Spot, which has been observed since the 17th century. If there is a semi-liquid or solid core on the planet, there must be a strong greenhouse effect.
According to some scientists, Jupiter plays the role of a kind of “vacuum cleaner” in the solar system - its powerful magnetic-gravitational field intercepts comets, asteroids and other bodies wandering in the Universe. A clear example was the capture and fall of the comet Shoemaker-Levy 9 onto Jupiter in 1994. The force of gravity turned out to be so strong that the comet split into separate fragments, which crashed into the atmosphere of Jupiter at a speed of over 200 thousand km/h. Each explosion reached millions of megatons of power, and observers from Earth saw explosion stains and diverging waves of excited atmosphere.
At the beginning of 2003, the number of Jupiter's satellites reached 48, a third of which have their own names. Many of them are characterized by reverse rotation and small sizes - from 2 to 4 km. The four largest satellites - Ganymede, Callisto, Io, Europa - are called Galileans. The satellites are composed of hard stone material, apparently of silicate composition. Active volcanoes, traces of ice and, possibly, liquids, including water, were found on them.
Saturn, The “ringed” planet is no less interesting. Its average density, calculated from the apparent radius, is very low - 0.69 g/cm 3 (without atmosphere - about 5.85 g/cm 3). The thickness of the atmospheric layer is estimated at 37-40 thousand km. A distinctive feature of Saturn is its ring located above the cloud layer of the atmosphere. Its diameter is 274 thousand km, which is almost twice the diameter of the planet, and its thickness is about 2 km. Based on observations from space stations, it has been established that the ring consists of a number of small rings located at different distances from each other. The substance of the rings is represented by solid fragments, apparently silicate rocks and ice blocks ranging in size from a speck of dust to several meters. Atmospheric pressure on Saturn is 1.5 times higher than on Earth, and the average surface temperature is about -180°C. The planet's magnetic field is almost half as strong as the Earth's, and its polarity is opposite to the polarity of the Earth's field.
30 satellites have been discovered near Saturn (as of 2002). The most distant of them, Phoebe (diameter about km) is located 13 million km from the planet and revolves around it in 550 days. The closest one is Mimas (diameter 195 km) located at 185.4 thousand km and makes a full revolution in 2266 hours. The mystery is the presence of hydrocarbons on the satellites of Saturn, and possibly on the planet itself.
Uranus. The axis of rotation of Uranus is located almost in the plane of its orbit. The planet has a magnetic field, the polarity of which is opposite to that of the Earth, and the intensity is less than that of the Earth.
In the dense atmosphere of Uranus, whose thickness is 8500 km, ring formations, spots, vortices, and jet streams were discovered, which indicates a restless circulation of air masses. The wind directions generally coincide with the rotation of the planet, but at high latitudes their speed increases. The greenish-blue color of the cold atmosphere of Uranus may be due to the presence of [OH - ] radicals. The helium content in the atmosphere reaches 15%; methane clouds have been found in the lower layers.
Around the planet, 10 rings ranging in width from several hundred meters to several kilometers, consisting of particles about 1 m in diameter, were discovered. Moving inside the rings are stone blocks of irregular shape and a diameter of 16-24 km, called “shepherd” satellites (probably asteroids).
Among the 20 satellites of Uranus, five stand out for their significant sizes (from 1580 to 470 km in diameter), the rest are less than 100 km. They all look like asteroids captured by the gravitational field of Uranus. On the spherical surface of some of them, giant linear stripes were noticed - cracks, possibly traces of glancing impacts of meteorites.
Neptune- the most distant planet from the Sun. Atmospheric clouds are formed mainly by methane. In the upper layers of the atmosphere there are wind currents rushing at supersonic speeds. This means the existence of temperature and pressure gradients in the atmosphere, apparently caused by the internal heating of the planet.
Neptune has 8 rocky satellites, three of which are of significant size: Triton (diameter 2700 km), Nerida (340 km) and Proteus (400 km), the rest are smaller - from 50 to 190 km.
Pluto- the most distant of the planets, discovered in 1930, does not belong to the giant planets. Its mass is 10 times less than the earth's.
Rotating rapidly around its axis, Pluto has a highly elongated elliptical orbit, and therefore from 1969 to 2009 it will be closer to the Sun than Neptune. This fact may be additional evidence of its “non-planetary” nature. It is likely that Pluto belongs to bodies from the Kuiper belt, discovered in the 90s of the 20th century, which is an analogue of the asteroid belt, but beyond the orbit of Neptune. Currently, about 40 such bodies with a diameter of 100 to 500 km, very dim and almost black, with an albedo of 0.01 - 0.02 (the Moon's albedo is 0.05) have been discovered. Pluto may be one of them. The surface of the planet is obviously icy. Pluto has a single satellite, Charon, with a diameter of 1190 km, with an orbit passing 19 thousand km from it and an orbital period of 6.4 Earth days.
Based on the nature of the movement of the planet Pluto, researchers suggest the presence of another extremely distant and small (tenth) planet. At the end of 1996, it was reported that astronomers from the Hawaiian Observatory had discovered a celestial body consisting of ice blocks that rotates in a near-solar orbit beyond Pluto. This minor planet does not yet have a name and is registered under the number 1996TL66.
Moon- a satellite of the Earth, rotating from it at a distance of 384 thousand km, whose size and structure bring it closer to the planets. The periods of axial and sidereal rotation around the Earth are almost equal (see Table 3.1), which is why the Moon always faces us with one side. The appearance of the Moon for an earthly observer is constantly changing in accordance with its phases - new moon, first quarter, full moon, last quarter. The period of complete change of lunar phases is called synodic month, which on average is equal to 29.53 Earth days. It doesn't match sidereal(to the stars) month constituting 27.32 days, during which the Moon makes a full revolution around the Earth and at the same time - a revolution around its axis in relation to the Sun. During the new moon, the Moon is between the Earth and the Sun and is not visible from the Earth. During a full moon, the Earth is between the Moon and the Sun and the Moon is visible as a full disk. Associated with the positions of the Sun, Earth and Moon solar And lunar eclipses- positions of the luminaries at which the shadow cast by the Moon falls on the surface of the Earth (solar eclipse), or the shadow cast by the Earth falls on the surface of the Moon (lunar eclipse).
The lunar surface is an alternation of dark areas - “seas”, corresponding to flat plains, and light areas - “continents”, formed by hills. The height differences reach 12-13 km, the highest peaks (up to 8 km) are located near the South Pole. Numerous craters ranging in size from several meters to hundreds of kilometers are of meteorite or volcanic origin (in the Alphonse crater, the glow of the central mountain and the release of carbon were discovered in 1958). Intense volcanic processes characteristic of the Moon in the early stages of development are now weakened.
Samples of the upper layer of lunar soil - regolith, taken by Soviet spacecraft and American astronauts, showed that igneous rocks of basic composition - basalts and anorthosites - emerge on the surface of the Moon. The former are characteristic of “seas”, the latter - of “continents”. The low density of regolith (0.8-1.5 g/cm3) is explained by its high porosity (up to 50%). The average density of the darker “marine” basalts is 3.9 g/cm3, and the lighter “continental” anorthosites is 2.9 g/cm3, which is higher than the average density of crustal rocks (2.67 g/cm3) . The average density of the Moon's rocks (3.34 g/cm3) is lower than the average density of the Earth's rocks (5.52 g/cm3). They assume a homogeneous structure of its interior and, apparently, the absence of a significant metallic core. Up to a depth of 60 km, the lunar crust is composed of the same rocks as the surface. The Moon has not detected its own dipole magnetic field.
In terms of chemical composition, lunar rocks are close to those on Earth and are characterized by the following indicators (%): SiO 2 - 49.1 - 46.1; MgO - 6.6-7.0; FeO - 12.1-2.5; A1 2 O 3 - 14.7-22.3; CaO -12.9-18.3; Na 2 O - 0.6-0.7; TiO 2 - 3.5-0.1 (the first numbers are for the soil of the lunar “seas”, the second - for continental soil). The close similarity of the rocks of the Earth and the Moon may indicate that both celestial bodies were formed at a relatively short distance from each other. The Moon formed in a near-Earth “satellite swarm” approximately 4.66 billion years ago. The bulk of iron and fusible elements at this time had already been captured by the Earth, which probably determined the absence of an iron core on the Moon.
Its small mass allows the Moon to retain only a very rarefied atmosphere consisting of helium and argon. Atmospheric pressure on the Moon is 10 -7 atm during the day and ~10 -9 atm at night. The absence of an atmosphere determines large daily fluctuations in surface temperature - from -130 to 180C.
Exploration of the Moon began on January 2, 1959, when the first Soviet automatic station, Luna-1, launched towards the Moon. The first humans were American astronauts Neil Armstrong and Edwin Aldrin, who landed on the moon on July 21, 1969 on the Apollo 11 spacecraft.
