Terrestrial planets. The terrestrial planets include: Mercury, Venus, Earth and Mars. According to their physical characteristics, the planets of the solar system

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Terrestrial planets These are the planets: Earth, Venus, Mercury and Mars. They are also called inner planets, in contrast to the outer planets - the giant planets. https://www.youtube.com/user/Kralizets/videos?view=0

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Terrestrial planets have high densities. They consist mainly of oxygen, silicon, iron, magnesium, aluminum and other heavy elements. https://www.youtube.com/user/Kralizets/videos?view=0

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All terrestrial planets have the following structure: in the center there is a CORE made of iron with an admixture of nickel. MANTLE, consists of silicates. CRUST, formed as a result of partial melting of the mantle and also consisting of silicate rocks, but enriched in incompatible elements. Of the terrestrial planets, Mercury does not have a crust, which is explained by its destruction as a result of meteorite bombardment. The Earth differs from other terrestrial planets in the high degree of chemical differentiation of matter and the wide distribution of granites in the crust. https://www.youtube.com/user/Kralizets/videos?view=0

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Mercury This planet is closest to the sun. The existence of this planet was mentioned in ancient Sumerian writings, which date back to the third millennium BC. This planet got its name from the Roman pantheon, Mercury, the patron saint of merchants, who also had his Greek counterpart, Hermes. https://www.youtube.com/user/Kralizets/videos?view=0

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Mercury Mercury completely circles the sun in eighty-eight Earth days. It travels around its axis in less than sixty days, which by Mercury standards is two-thirds of a year. The temperature on the surface of Mercury can vary from +430 degrees on the sun side to +180 degrees on the shadow side. In our solar system, these differences are the strongest. https://www.youtube.com/user/Kralizets/videos?view=0

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Mercury Mercury is the smallest planet of the Earth group. In addition, this planet is the fastest planet in our system. The surface of Mercury is similar to the surface of the Moon - all strewn with craters. An unusual phenomenon can be observed on Mercury, which is called the Joshua effect. When the sun on Mercury reaches a certain point, it stops and begins to go in the opposite direction https://www.youtube.com/user/Kralizets/videos?view=0

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Venus Venus is the second inner planet of the Solar System with an orbital period of 224.7 Earth days. The planet got its name in honor of Venus, the goddess of love from the Roman pantheon. Venus is the third brightest object in the Earth's sky after the Sun and Moon. It reaches its maximum brightness shortly before sunrise or some time after sunset, which gives rise to the name it is also called the Evening Star or the Morning Star. https://www.youtube.com/user/Kralizets/videos?view=0

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Venus The pressure at the surface reaches 93 atm, the temperature is 750 K (475 °C). This exceeds the surface temperature of Mercury, which is twice as close to the Sun. The reason for such high temperatures on Venus is the greenhouse effect created by the dense carbon dioxide atmosphere. The wind, which is very weak at the surface of the planet (no more than 1 m/s), near the equator at an altitude of over 50 km intensifies to 150-300 m/s. Observations from automatic space stations detected thunderstorms in the atmosphere. https://www.youtube.com/user/Kralizets/videos?view=0

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Venus The surface of Venus is dotted with thousands of volcanoes. Science fiction writers described Venus as similar to Earth. It was believed that Venus was shrouded in clouds. This means that the surface of this planet should be dotted with swamps. In reality, everything is completely different - in the early seventies, the union sent spaceships to the surface of Venus, which clarified the situation. It turned out that the surface of this planet is made up of continuous rocky deserts, where there is absolutely no water. Of course, at such a high temperature there could never be any water. https://www.youtube.com/user/Kralizets/videos?view=0

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Earth Earth is the third planet from the Sun in the Solar System, the largest in diameter, mass and density among the terrestrial planets. Most often referred to as the World, the Blue Planet, and sometimes Terra. The only body currently known to man, the Solar System in particular and the Universe in general, inhabited by living organisms. https://www.youtube.com/user/Kralizets/videos?view=0

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Earth The future of the planet is closely connected with the future of the Sun. As a result of the accumulation of “spent” helium in the Sun’s core, the star’s luminosity will begin to slowly increase. The sun's brightness will increase by 10% over the next 1.1 billion years and by another 40% over the next 3.5 billion years. According to some climate models, increasing the amount of solar radiation falling on the Earth's surface will lead to catastrophic consequences, including the possibility of complete evaporation of all oceans. https://www.youtube.com/user/Kralizets/videos?view=0

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Earth Scientific evidence indicates that the Earth formed from a solar nebula about 4.54 billion years ago, and shortly thereafter acquired its only natural satellite, the Moon. Life appeared on Earth about 3.5 billion years ago. Since then, the Earth's biosphere has significantly changed the atmosphere and other abiotic factors, causing the quantitative growth of aerobic organisms, as well as the formation of the ozone layer, which, together with the Earth's magnetic field, weakens harmful solar radiation, thereby maintaining conditions for life on Earth. https://www.youtube.com/user/Kralizets/videos?view=0

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The Moon is the only satellite of the Earth. The second brightest object on Earth and the fifth largest natural satellite of a planet in the solar system. The average distance between the centers of the Earth and the Moon is 384,467 km. Light launched from the Earth reaches the Moon in 1.255 seconds. The Moon is the only astronomical object outside the Earth that humans have visited. https://www.youtube.com/user/Kralizets/videos?view=0

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Mars This planet is named after the famous god of War in Rome, because the color of this planet is very similar to the color of blood. This planet is also called the “red planet”. It is believed that this color of the planet is associated with iron oxide, which is present in the atmosphere of Mars. Mars is the seventh largest planet in the solar system. It is considered to be the home of the Valles Marineris - a canyon that is much longer and deeper than the famous Grand Canyon in the USA. Here, by the way, there is also Olympus - the highest and most famous mountain in the entire solar system. https://www.youtube.com/user/Kralizets/videos?view=0

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Mars But the atmosphere of this planet is one hundred times less dense than the earth’s. But this is enough to maintain the weather system on the planet - that means wind and clouds. https://www.youtube.com/user/Kralizets/videos?view=0 Satellites of Mars Both satellites rotate around their axes with the same period as around Mars, therefore they are always turned to the planet with the same side. The tidal influence of Mars slows down the movement of Phobos, lowering its orbit. Deimos is moving away from Mars. According to one hypothesis, Deimos and Phobos are former asteroids captured by the gravitational field of Mars. However, the fairly regular shape of their orbits and the position of the orbital planes casts doubt on this version. Another assumption about the origin of Phobos and Deimos is the disintegration of the satellite of Mars into two parts. https://www.youtube.com/user/Kralizets/videos?view=0 Slide 20

It was discovered by the American astronomer Asaph Hall in 1877 and named after the ancient Greek god of horror, companion of the god of war Ares. There are only two geological features on Deimos that have their own names. These are the craters Swift and Voltaire, named after two writers who predicted the existence of two moons on Mars even before their discovery. Deimos https://www.youtube.com/user/Kralizets/videos?view=0

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Terrestrial planets

Performed by student HB-5 Shiryaeva Sofia

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According to their physical characteristics, the planets of the solar system are divided into terrestrial planets and giant planets

The terrestrial planets include: Mercury, Venus, Earth and Mars

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General characteristics of the dynamic properties of terrestrial planets

The similarity of the terrestrial planets does not exclude significant differences in mass, size and other characteristics

GENERAL CHARACTERISTICS OF THE TERRESTRIAL PLANETS

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Mercury

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Mercury is the “second moon”! When the Mariner 10 spacecraft transmitted the first close-up images of Mercury, astronomers threw up their hands: there was a second Moon in front of them!

Mercury is very similar to the Moon. There was a period in the history of both celestial bodies when lava flowed to the surface in streams.

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Mercury is located close to the Sun. Mercury's maximum elongation is only 28 degrees, making it very difficult to observe. Mercury has no satellites.

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The surface of Mercury in photographs taken at close range is replete with craters (US MESSENGER spacecraft)

This reticulated topography is the territory of the Caloris Basin. Pantheon Fossae or Depression of the Pantheon is its center. The relief of the basin became this way due to the fall of a giant meteorite. The pool is the result of the outflow of lava from the bowels of the planet after a collision.

The shadows in the photo give the craters an additional resemblance to the cartoon character. The diameter of Mickey's "head" is 105 kilometers.

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Mercury is located very close to the Sun and captures the solar wind with its gravity. A helium atom captured by Mercury remains in the atmosphere for an average of 200 days.

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Mercury has a weak magnetic field, which was discovered by the Mariner 10 spacecraft.

The high density and presence of a magnetic field indicate that Mercury must have a dense metallic core. The core accounts for 80% of Mercury's mass.

The radius of the core is 1800 km (75% of the radius of the planet).

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Surface temperatures in Mercury's polar regions, which are never illuminated by the Sun, can hover around -210°C. There may be water ice present. The maximum surface temperature of Mercury recorded by sensors is + 410 °C. Temperature differences on the day side due to the change of seasons caused by the elongation of the orbit reach 100 °C.

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All planets (except Uranus) rotate around their axis counterclockwise (when viewed from the North Pole), while Venus rotates in the opposite direction - clockwise.

The rotation axis of Venus is almost perpendicular to the orbital plane, so there are no seasons - one day is similar to another, has the same duration and the same weather.

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The weather uniformity is further enhanced by the specificity of the Venusian atmosphere - its strong greenhouse effect.

The existence of the Venusian atmosphere was first discovered in 1976 by M.V. Lomonosov during observations of its passage across the solar disk.

Studies of the reflected spectrum of Venus using telescopes have shown that the atmosphere is very different from the atmosphere of Earth.

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An ultraviolet image taken from the Pioneer Venus interplanetary station shows the planet's atmosphere densely filled with clouds, lighter in the polar regions (top and bottom of the image).

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Near the surface of Venus, it was possible to measure wind speeds of approximately 13 km/h. They are relatively weak, however they can move small particles of sand or the like. At higher altitudes there are stronger winds. At an altitude of 45 km, wind movements at a speed of 175 km/h were observed, and strong vertical air movements were also detected. Probes conducting research on Venus brought data that was deciphered as evidence of lightning.

The sky on Venus is a bright yellow-green hue.

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The surface of Venus has many features similar to those of Earth. Most of the planet is dominated by relatively low-lying planes characterized by excessive volcanic structures, but there are also large highland areas with mountain ranges, volcanoes, and fissure systems. The largest highland area, called Aphrodite's Land, is in the equatorial region of Venus. Its size is approximately equal to the size of Africa.

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According to the most plausible hypothesis, the Venusian core has not yet begun to solidify and therefore convective jets are not born there, swirling due to the rotation of the planet and generating a magnetic field. Otherwise, such a field should still have arisen

Whether Venus has a solid or liquid core is not yet known for sure.

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In relation to Venus, we can say that the climate and weather on this planet are one and the same. On Venus, these conditions are practically unchanged throughout the day and year. With an almost perpendicular position of the rotation axis of Venus to the orbital plane (inclination 3), fluctuations in the values of meteorological elements remain almost unchanged during the day (their duration is 234 Earth days). Temperature fluctuations at the surface do not exceed 5-15 C.

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The appearance of life, living matter - the biosphere - on our planet was a consequence of its evolution. In turn, the biosphere had a significant impact on the entire further course of natural processes. So, if there were no life on Earth, the chemical composition of its atmosphere would be completely different.

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Based on records of vibrations of the earth's surface - seismograms - it was established that the interior of the Earth consists of three main parts: the crust, the shell (mantle) and the core.

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In the 30s seismologists have established that the Earth also has an inner, solid core. The current value of the depth of the boundary between the inner and outer cores is approximately 5150 km.

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Back in 1912, German researcher Alfred Wegener put forward the hypothesis of continental drift.

The first magnetic maps of the Pacific floor off the coast of North America, in the area of the Juan de Fuca Ridge, showed the presence of mirror symmetry. An even more symmetrical pattern is found on both sides of the central ridge in the Atlantic Ocean.

Using the concept of continental drift, known today as “new global tectonics,” it is possible to reconstruct the relative positions of continents in the distant past. It turns out that 200 million years ago it formed a single continent.

In the 50s, when studies of the ocean floor were widely carried out, the hypothesis of large horizontal movements in the lithosphere received new confirmation. A significant role in this was played by the study of the magnetic properties of the rocks that make up the ocean floor.

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The larger the falling bodies, the more they heated the Earth. The impact energy was released not on the surface, but at a depth equal to approximately two diameters of the embedded body. And since the bulk at this stage was supplied to the planet by bodies several hundred kilometers in size, the energy was released in a layer about 1000 km thick. It did not have time to radiate into space, remaining in the bowels of the Earth. As a result, the temperature at depths of 100–1000 km could approach the melting point. The additional increase in temperature was probably caused by the decay of short-lived radioactive isotopes.

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Water covers more than 70% of the surface of the globe, and the average depth of the World Ocean is about 4 km. The mass of the hydrosphere is approximately 1.46 * 10 kg. This is 275 times the mass of the atmosphere, but only 1/4000 of the mass of the entire Earth. The hydrosphere is 94% made up of the waters of the World Ocean, in which salts are dissolved (3.5% on average), as well as a number of gases. The top layer of the ocean contains 140 trillion tons of carbon dioxide and 8 trillion tons of dissolved oxygen. tons

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The apparent magnitude of the full Moon in the earth's sky is −12.71m. The illumination created by the full Moon near the Earth's surface in clear weather is 0.25 - 1 lux.

The Moon is the only astronomical object outside the Earth that humans have visited.

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Because Mars is further from the Sun than Earth; Mars takes longer to complete one revolution around the Sun. A year on Mars lasts 687 Earth days. The speed of Mars is approximately 24 km/s, and the planet rotates in the same direction as the Earth - counterclockwise (when viewed from the north pole of the planet). A Martian day lasts 24 hours, 37 minutes, 23 seconds, which is very close to the length of an Earth day.

The tilt of the planet's axis is approximately 25 degrees, as a result of which seasonal changes on Mars occur similar to those on Earth. Because of Mars' elliptical orbit, it is summer in the southern hemisphere when the planet is closest to the Sun, and winter in the northern hemisphere.

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The main components of the Martian atmosphere are carbon dioxide (95.3%), nitrogen (2.7%), and argon (1.6%). Small amounts of oxygen, carbon monoxide, water vapor, and other substances make up the rest. The average surface pressure of the atmosphere is less than one hundredth the average surface pressure of the Earth's atmosphere, and it varies with time of year and altitude. The Martian atmosphere is subject to daily and seasonal temperature changes.

Gravity on Mars is almost 3 times less than on Earth. That is, while walking on this planet, you could jump three times higher than on Earth.

Spacecraft that have visited Mars have confirmed the presence of water in the form of large reserves below the surface and in the form of ice on the surface.

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The color of the Martian surface ranges from orange to brown-black. The darker substances are weathered basalt rock, and the lighter ones are iron oxides.

Photographs of the Martian surface taken by American probes that landed on the surface of Mars as part of the Viking mission confirm the presence of layers that are carried by winds, and also show stones and boulders scattered on the surface.

Mars is a huge red desert. The deep canyons of Mars are carved by winds. Volcanoes rise on the surface and impact craters stretch out.

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Currently, the structure of the gravitational field of Mars has been studied in detail. It indicates a slight deviation from the uniform distribution of density on the planet. The core can have a radius of up to half the radius of the planet. Apparently, it consists of pure iron or an alloy of Fe-FeS (iron-iron sulfide) and possibly hydrogen dissolved in them. Apparently, the core of Mars is partially or completely liquid.

Mars should have a thick crust 70-100 km thick. Between the core and the crust there is a silicate mantle enriched in iron. Red iron oxides present in surface rocks determine the color of the planet. Now Mars continues to cool. The planet's seismic activity is weak.

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Olympus Mons on Mars is the highest mountain in the solar system. Its height is 27 km. This is a volcano. The relatively young lava on its slopes indicates its possible activity.

Valles Marineris is the longest and deepest canyon in the solar system. It stretches along the equator for 4000 km, and its depth reaches 7 kilometers. One of the main versions of the formation of a canyon resembling a scar is a grandiose catastrophe associated with the collision of Mars with a huge cosmic body.

Canyon on Mars - trace of a great cosmic catastrophe on the planet

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Deimos (Greek Δείμος “horror”) is one of two satellites of Mars. It was discovered by American astronomer Asaph Hall in 1877

The diameter of Deimos is about 13 km, it orbits at an average distance of 6.96 planet radii (approximately 23,500 km), with an orbital period of 30 hours 17 minutes 55 s.

Deimos, like the Moon, has the angular velocity of its orbit equal to the angular velocity of its own rotation, so it is always turned to Mars with the same side.

Phobos (ancient Greek φόβος “fear”) is one of two satellites of Mars. It was discovered by American astronomer Asaph Hall in 1877.

The dimensions of Phobos are 27 × 22 × 18 km. Phobos orbits at an average distance of 2.77 Mars radii from the planet's center (9400 km). It makes one revolution in 7 hours 39 minutes 14 seconds, which is about three times faster than the rotation of Mars around its own axis. As a result, in the Martian sky, Phobos rises in the west and sets in the east.

Phobos Deimos

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AXIS OF ROTATION OF THE TERRESTRIAL PLANETS

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THANK YOU FOR YOUR ATTENTION!

Lesson objectives:

Educational : formation of students’ ideas about the structure and physical characteristics of the terrestrial planets.

Developmental : formation of students’ worldview, development of skills to work with additional literature, briefly, clearly and quickly express their thoughts, development of logical thinking.

Educational : developing skills to work in groups, instilling respect for one’s peers.

Lesson objectives:

Give an idea of the structure and physical characteristics of the terrestrial planets.
Organize group work of students to compile a summary table.
Organize diagnostics of the level of assimilation of knowledge about the terrestrial planets.

Equipment: computer, multimedia projector, interactive course “Open Astronomy” version 2.6, screen, presentation “Terrestrial Planets” ( Appendix 1), articles from the encyclopedia on astronomy of the Avanta + publishing house.

Lesson Plan

Lesson steps	Time, min.	Methods and techniques
1. Organizational moment.		Teacher's story.
2. Studying new material.		Group work. Working with additional literature.
		Student performance. Teacher's story. Write in notebooks and on the board. Working with a summary table.
		Testing.
5. Summing up.		Filling out the form.

Lesson progress

Epigraph for the lesson:

“Seven wandering stars cross the threshold of Olympus.
Each circle is completed at its own constant time.
The night lamp is the Moon, light-winged Mercury, Venus.
Mars is daring, gloomy Saturn, and the cheerful Sun.
And the progenitor Jupiter, who gave birth to all nature.
They also divide the race among themselves: there is also in people
Sun, Mercury, Moon, Mars, Venus, Saturn and Jupiter.
For we also receive as our inheritance the streams of ether
Tears and laughter, anger, desire, the gift of speech and sleep and birth.
Saturn gives us tears, Mercury gives us speech, Jupiter gives us birth;
Our anger is from Mars, from the Moon - a dream, from Venus - desire;
Laughter comes from the Sun: it makes you laugh
Just like the human mind, so is the whole infinite world.

Theon of Alexandria

Lesson stage	Teacher activities	Student activities
1. Organizational moment.	The teacher formulates the purpose of the lesson, gives instructions for working in a group, and an assignment for groups. Rules for working in groups 1. Everyone needs to actively participate in the work of the group. 2. You need to listen and understand each other, be polite, and not interrupt your friend. 3. The group work procedure (given time) must be followed. Exercise Using additional literature, find the following information about the terrestrial planets (each group is looking for information about one planet): mass, diameter, density, average distance from the Sun, rotation period, orbital period, planet topography, atmosphere, magnetic field, satellites, temperature on surfaces. Information is written down on cards.	Listen to the teacher's explanation.
2. Studying new material.	Control over the work of groups. The teacher plays the role of a consultant.	Work in groups.
3. Generalization of the material being studied.	Supplements the students' story using a presentation (see presentation “Terrestrial Planets”) and computer models (see disk “Open Astronomy”, model 4.3 - rotation of Mercury, model 4.5 - phases of Venus).	One representative from each group voices the information found during group work at the board, the rest of the students fill out a summary table. ( Appendix 2)
4. Testing the acquired knowledge.	The teacher offers students a short test on the material studied in class. Each group receives a version of the test and completes it. Next, a self-test is carried out, the results of which are entered into the results table.	Perform the test. Finish the sentences you started. 3. The densest atmosphere of the planets in this group has... 4. Of these planets, only.. has a magnetic field and radiation belts. 5. The largest number of natural satellites has... 6. Mount Olympus is on the planet... 7. The surface temperature remains almost constant day and night for... 1. Mercury 2. Venus 3. Earth 4. Mars
5. Summing up.	The results of the lesson are summed up. The teacher offers students a questionnaire in which they express their opinion about the lesson.

Expected result

Presentation of ideas about the terrestrial planets in the form of a table on the board and in students’ notebooks.
High performance in completing the test task.
Positive assessment of the lesson by students.

Terrestrial planets
Vikonali 11th grade student
Giniyatullin Vladislav
that
Locust Karina

According to their physical characteristics, the planets of the solar system are divided into terrestrial planets and giant planets
The terrestrial planets include: Mercury, Venus, Earth and Mars

General characteristics of the dynamic properties of terrestrial planets
The similarity of the terrestrial planets does not exclude significant
differences in weight, size and other characteristics
GENERAL CHARACTERISTICS OF THE TERRESTRIAL PLANETS

Mercury

Mercury is the “second moon”!
When the Mariner 10 spacecraft transmitted the first
Close-up shots of Mercury, astronomers
They clasped their hands: in front of them was the second Moon!
Mercury is very similar to the Moon. In the history of both celestial bodies
There was a period when lava flowed to the surface in streams.

Mercury is the planet closest to the Sun out of the 9 main planets of the solar system, and, in accordance with Kepler's 3rd law, has the shortest period of revolution around the Sun (88 Earth days). And the highest average orbital speed (48 km/s).
Mercury is located close to the Sun. Mercury's maximum elongation is only 28 degrees, making it very difficult to observe.
Mercury has no satellites.

The surface of Mercury in photographs taken from close up
distances, replete with craters (American spacecraft MESSENGER)
This reticulated topography is the territory of the Caloris Basin. Pantheon Fossae or Depression of the Pantheon is its center. The relief of the basin became this way due to the fall of a giant meteorite. The pool is the result of the outflow
lava from the bowels of the planet after a collision.
The shadows in the photo give the craters an additional resemblance to the cartoon character. The diameter of Mickey's "head" is 105 kilometers.

Data on the atmosphere of Mercury indicates only its strong rarefaction. Because the critical speed is too low and the temperature too high for Mercury to retain an atmosphere. However, in 1985, using spectral analysis, an extremely thin layer of sodium atmosphere was discovered. Obviously, atoms of this metal are released from the surface when it is bombarded by streams of particles flying from the Sun.
Mercury is located very close to the Sun and captures the solar wind with its gravity.
A helium atom captured by Mercury remains in the atmosphere for an average of 200 days.

Mercury has a weak magnetic field,
which was discovered by the Mariner 10 spacecraft.
High density and availability
magnetic field show that Mercury should have
dense metal core.
The core accounts for
80% of Mercury's mass.
The radius of the core is 1800 km (75% of the radius of the planet).

Surface temperature in
The polar regions of Mercury, which the Sun never illuminates, can remain around -210 °C.
There may be water ice present.
Maximum temperature
surface of Mercury,
registered by sensors, + 410 °C.
Temperature changes
on the day side
due to the change of seasons,
caused by the elongation of the orbit,
reach 100 °C.

Venus is the second terrestrial planet after Mercury in terms of distance from the Sun (108 million km). Its orbit has the shape of an almost perfect circle. Venus orbits the Sun in 224.7 Earth days at a speed of 35 km/sec.
All planets (except Uranus) rotate around their axis counterclockwise (when viewed from the North Pole), while Venus rotates in the opposite direction - clockwise.
The rotation axis of Venus is almost perpendicular to the orbital plane, so there are no seasons - one day is similar to another, has the same duration and the same weather.

The weather uniformity is further enhanced by the specificity of the Venusian atmosphere - its strong greenhouse effect.
The existence of the Venusian atmosphere was first discovered in 1976 by M.V. Lomonosov during observations of its passage across the solar disk.
Studies of the reflected spectrum of Venus using telescopes have shown that the atmosphere is very different from the atmosphere of Earth.

The main components of Venus' clouds are droplets of sulfuric acid and solid sulfur particles. Using probes, it was discovered that below the clouds the atmosphere contains approximately 0.1 to 0.4% percent water vapor and 60 parts per million free oxygen. The presence of these components indicates that Venus may once have had water, but the planet has now lost it.
An ultraviolet image taken from the Pioneer Venus interplanetary station shows the planet's atmosphere densely filled with clouds, lighter in the polar regions (top and bottom of the image).

The earth has one unique feature - it has life. However, this is not noticeable when looking at the Earth from space. Clouds floating in the atmosphere are clearly visible. Continents can be seen through the gaps in them.
Most of the Earth is covered by oceans.
The appearance of life, living matter - the biosphere - on our planet was a consequence of its evolution. In turn, the biosphere had a significant impact on the entire further course of natural processes. So, if there were no life on Earth, the chemical composition of its atmosphere would be completely different.

It’s not easy to “look” into the depths of the Earth. Even the deepest wells on land barely penetrate the 10-kilometer mark, and under water they manage to penetrate the basalt foundation no more than 1.5 km after passing through the sedimentary cover. Seismic waves come to the rescue.
Based on records of vibrations of the earth's surface - seismograms - it was established that the interior of the Earth consists of three main parts: the crust, the shell (mantle) and the core.

Opened in 1905 changes in the Earth's magnetic field in space and intensity led to the conclusion that it originates in the depths of the planet. The most likely source of such a field is a liquid iron core. There should be current loops in it, roughly reminiscent of turns of wire in an electromagnet, which generate various components of the geomagnetic field.
In the 30s seismologists have established that the Earth also has an inner, solid core. The current value of the depth of the boundary between the inner and outer cores is approximately 5150 km.

Back in 1912, German researcher Alfred Wegener put forward the hypothesis of continental drift.
The first magnetic maps of the Pacific floor off the coast of North America, in the area of the Juan de Fuca Ridge, showed the presence of mirror symmetry. An even more symmetrical pattern is found on both sides of the central ridge in the Atlantic Ocean.
Using the concept of continental drift, known today as “new global tectonics,” it is possible to reconstruct the relative positions of continents in the distant past. It turns out that 200 million years ago it formed a single continent.
In the 50s, when studies of the ocean floor were widely carried out, the hypothesis of large horizontal movements in the lithosphere received new confirmation. A significant role in this was played by the study of the magnetic properties of the rocks that make up the ocean floor.

It is known that our planet was formed about 4.6 billion years ago. During the formation of the Earth from particles of the protoplanetary cloud, its mass gradually increased. The gravitational force increased, and consequently, the speed of particles falling on the planet. The kinetic energy of the particles turned into heat, and the Earth warmed up more and more. During impacts, craters appeared on it, and the substance ejected from them could no longer overcome gravity and fell back.
The larger the falling bodies, the more they heated the Earth. The impact energy was released not on the surface, but at a depth equal to approximately two diameters of the embedded body. And since the bulk at this stage was supplied to the planet by bodies several hundred kilometers in size, the energy was released in a layer about 1000 km thick. It did not have time to radiate into space, remaining in the bowels of the Earth. As a result, the temperature at depths of 100–1000 km could approach the melting point. The additional increase in temperature was probably caused by the decay of short-lived radioactive isotopes.

Currently, the Earth has an atmosphere with a mass of approximately 5.15 * 10 kg, i.e. less than a millionth of the planet's mass. Near the surface it contains 78.08% nitrogen, 20.05% oxygen, 0.94% inert gases, 0.03% carbon dioxide and in small quantities other gases.
Water covers more than 70% of the surface of the globe, and the average depth of the World Ocean is about 4 km. The mass of the hydrosphere is approximately 1.46 * 10 kg. This is 275 times the mass of the atmosphere, but only 1/4000 of the mass of the entire Earth. 94% of the hydrosphere is made up of the waters of the World Ocean, in which salts are dissolved (3.5% on average), as well as a number of gases. The top layer of the ocean contains 140 trillion tons of carbon dioxide and 8 trillion tons of dissolved oxygen. tons

The Moon is the only natural satellite of the Earth. The second brightest object in the earth's sky after the Sun and the fifth largest natural satellite of a planet in the solar system. The average distance between the centers of the Earth and the Moon is 384,467 km (0.002 57 AU).
The apparent magnitude of the full Moon in the earth's sky is −12.71m. The illumination created by the full Moon near the Earth's surface in clear weather is 0.25 - 1 lux.
The Moon is the only astronomical object outside the Earth that humans have visited.

The orbit of Mars lies approximately one and a half times further than the earth. It is somewhat elliptical, so the planet's distance from the Sun varies from a minimum, at perihelion, 206.7 million km to a maximum, at aphelion, 249.2 million km.
Because Mars is further from the Sun than Earth; Mars takes longer to complete one revolution around the Sun. A year on Mars lasts 687 Earth days. The speed of movement of Mars is approximately 24 km/s, and the planet rotates in the same direction as the Earth - counterclockwise (when viewed from the north pole of the planet). A Martian day lasts 24 hours, 37 minutes, 23 seconds, which is very close to the length of the earth's day.
The tilt of the planet's axis is approximately 25 degrees, as a result of which seasonal changes on Mars occur similar to those on Earth. Because of Mars' elliptical orbit, it is summer in the southern hemisphere when the planet is closest to the Sun, and winter in the northern hemisphere.

Characteristics of terrestrial planets. Terrestrial planets are characterized by:
presence of atmosphere,
small sizes,
small number of satellites,
hard surface.

Earth is the third planet from the Sun

The earth is removed from
Sun at 149.5 million km.
Its orbit is close to
ellipse. Rotates
around the sun and around
own axis.
A day on Earth is 24 hours.
An Earth year lasts 365
days.

Atmosphere - the air envelope of the Earth

Atmospheric composition:
78% nitrogen, 21% oxygen, 1% other gases
and impurities.
The atmosphere protects
Earth from the fall
meteorites.
Oxygen is needed
for the breath of the living
organisms.

Earth is a unique planet.

The Earth is so far away from the Sun
distance that allows
provide a certain
temperature conditions, favorable
for life.

This is what the Earth looks like from the surface of the Moon.

On the surface
Moon
distinguishable
dark areas
- "sea" and
lighter
– continents
or
continents.
They occupy
about 83% of
all
surfaces.
The surface of the Moon is dotted with craters and “ring” mountains.

In 1970, the first automatic
lunar self-propelled vehicle "Lunokhod - 1".

On July 21, 1969, Neil Armstrong became the first human astronaut from the United States
visited the moon.

Mars is the fourth planet from the sun.

Mars is on
distance 228 million
km from the Sun.
A year on Mars lasts 687
days.
A day is 24.5 hours.
Mars has 2 natural
satellites - Deimos and Phobos.
Prevails in the atmosphere
carbon dioxide (85%), water up to
0.1%, oxygen about 0.15%.

.

Mars is at its minimum distance from Earth
during confrontations. But once every 15–17 years
the planets are approaching as close as possible and Mars looks
the brightest orange-red star,
as a result of which Mars began to be considered an attribute of God
war.
.

Mars - god of war

Moons of Mars

The dimensions of Deimos are 13 kmx 12 km;
Phobos 21 kmX 26 km;
In 1877, scientist A. Hall discovered satellites on Mars. He was puzzled and
even scared, that’s why he called them “Phobos” (fear) and “Deimos”
(horror).
Phobos in Greek mythology, the deity personifying fear, the son
Ares and Aphrodite.
Deimos (from the Greek “horror”) is the son and satellite of Mars.

Surface relief of Mars

Telescopic exploration of Mars has discovered
seasonal changes on the planet. This is first of all
refers to the “white polar caps”,
which increase by autumn, and by spring
begin to melt, and from the poles
“Warming waves” are spreading.

slight removal
from the Sun;
relatively
small sizes;
lack of satellites
(or a few of them
quantity);
presence of solids
surfaces.
Next lesson
we'll meet
planets - giants and a small planet
Pluto.