The planets belonging to the terrestrial group - Mercury, Venus, Earth, Mars - have small sizes and masses, the average density of these planets is several times higher than the density of water; they rotate slowly around their axes; they have few satellites (Mercury and Venus have none at all, Mars has two tiny ones, Earth has one).
Similarities and differences are also found in the study of planetary atmospheres terrestrial group Khoroshavina S.G. Concepts modern natural science. Course of lectures - Rostov-on-Don, 2006.
Mercury
Mercury is the fourth brightest planet: at its maximum brightness it is almost as bright as Sirius, only Venus, Mars and Jupiter are brighter than it. However, Mercury is a very difficult object to observe due to its small orbit and therefore proximity to the Sun. To the naked eye, Mercury is a point of light, but in a strong telescope it looks like a crescent or an incomplete circle. Changes in the appearance (phases) of the planet over time show that Mercury is a ball, illuminated by the Sun on one side, and completely dark on the other. The diameter of this ball is 4870 km.
Mercury slowly rotates around its axis, always facing the Sun with one side. Thus, the period of revolution around the Sun (Mercurian year) is about 88 Earth days, and the period of rotation around its axis is 58 days. It turns out that a year passes from sunrise to sunset on Mercury, that is, 88 Earth days. Indeed, the surface of Mercury is in many ways similar to the surface of the Moon, although we do not know whether there are actually seas and craters on the surface of Mercury. Mercury has a relatively high density among the planets solar system-- about 5.44 g/cm3. Scientists suggest that this is due to the presence of a massive metallic core (presumably made of molten iron with a density of up to 10 g/cm3, having a temperature of about 2000 K), containing more than 60% of the planet's mass and surrounded by a silicate mantle and probably a crust 60 - 100 km thick .
Venus
Venus is observed both as an “evening star” and as a “ morning Star" - Hesperus and Phosphorus, that’s what they called it in the ancient world. After the sun and the Moon, Venus is the brightest celestial body, and at night objects illuminated by it can cast shadows. Venus is also the closest planet to Earth. She is even called "sister of the Earth." Indeed, the radius of Venus is almost equal to that of the Earth (0.95), its mass is 0.82 that of the Earth. Venus has been studied quite well by people - both the Soviet Venus series spacecraft and the American Mariners approached the planet. Venus revolves around the Sun in 224.7 Earth days, but, unlike Mercury, nothing interesting is connected with this figure. Very interesting fact is associated with the period of rotation of the planet itself around its axis - 243 Earth days (in the opposite direction) and the period of rotation of the powerful Venusian atmosphere, which makes a complete revolution around the planet in... 4 days! This corresponds to a wind speed at the surface of Venus of 100 m/s or 360 km/h! It has an atmosphere first discovered by M.V. Lomonosov in 1761 during the passage of the planet across the disk of the sun. The planet is shrouded in a thick layer of white clouds, hiding its surface. The presence of thick clouds in the atmosphere of Venus, probably consisting of ice crystals, explains the high reflectivity of the planet - 60% of the incident sunlight is reflected from it. Modern scientists have established that the Venusian atmosphere consists of 96% carbon dioxide CO2. Nitrogen (almost 4%), oxygen, water vapor, noble gases, etc. (all less than 0.1%) are also present here. The basis of the thick cloud layer, located at an altitude of 50-70 km, is small drops of sulfuric acid with a concentration of 75-80% (the rest is water, actively “absorbed” by the acid droplets). There are active volcanoes on Venus, as it is reliably known that seismic and tectonic activity on Venus was very active relatively recently. Internal structure This pseudo-twin of the Earth is also similar to the structure of our planet.
Earth
Our earth seems to us so large and solid and so important to us that we tend to forget the humble position it occupies in the family of planets of the solar system. True, the Earth still has a rather thick atmosphere covering a thin, heterogeneous layer of water, and even a titular satellite with a diameter of approximately ½ of its diameter. However, these special signs of the Earth can hardly serve as a sufficient basis for our cosmic “egocentrism.” But, being a small astronomical body, the Earth is the most familiar planet to us. Radius of the globe R=6378 km. The rotation of the globe most naturally explains the change of day and night, the rising and setting of the stars. Some Greek scientists also guessed about the annual movement of the Earth around the Sun. The annual motion of the Earth moves the observer and thereby causes a visible displacement of closer stars relative to more distant ones. Strictly speaking, the center of gravity of the Earth-Moon system, the so-called barycenter, moves around the Sun; The Earth and Moon describe their orbits around this center during the month.
Our ideas about the internal structure and physical condition subsoil of the globe are based on a variety of data, among which seismology data (the science of earthquakes and the laws of propagation) are of significant importance elastic waves in the globe). The study of the propagation of elastic waves in the globe, arising during earthquakes or powerful explosions, made it possible to discover and study the layered structure of the earth's interior.
The air ocean surrounding the Earth - its atmosphere - is the arena in which various meteorological phenomena take place. The earth's atmosphere is mainly composed of nitrogen and oxygen.
The earth's atmosphere is conventionally divided into five layers: the troposphere, stratosphere, mesosphere, ionosphere and exosphere. The hydrosphere, or the World Ocean, whose surface is 2.5 times larger, has a great influence on many processes occurring on our planet. more area sushi. Earth has a magnetic field. Outside the dense layers of the atmosphere, it is surrounded by invisible clouds of very fast-moving particles high energy. These are the so-called radiation belts. The structure and properties of the surface of our planet, its shells and interiors, magnetic field and radiation belts are studied by a complex of geophysical sciences.
Mars
When the American Mariner 4 station first took pictures of Mars from a short distance in 1965, these photographs caused a sensation. Astronomers were ready to see anything but the lunar landscape. It was on Mars that those who wanted to find life in space had special hopes. But these aspirations did not come true - Mars turned out to be lifeless. According to modern data, the radius of Mars is almost half that of Earth (3390 km), and Mars is ten times less massive than Earth. This planet orbits the Sun in 687 Earth days (1.88 years). Solar days on Mars are almost equal to those on Earth - 24 hours 37 minutes, and the planet’s rotation axis is inclined to the orbital plane by 25), which allows us to conclude that the cycle is similar to the Earth’s (for Earth there are 23 seasons.
But all the dreams of scientists about the presence of life on the Red Planet melted away after the composition of the atmosphere of Mars was established. To begin with, it should be noted that the pressure at the surface of the planet is 160 times less than the pressure of the earth’s atmosphere. And it consists of 95% carbon dioxide, contains almost 3% nitrogen, more than 1.5% argon, about 1.3% oxygen, 0.1% water vapor, carbon monoxide is also present, traces of krypton and xenon have been found. Of course, no life can exist in such a rarefied and inhospitable atmosphere.
The average annual temperature on Mars is approximately -60; temperature changes during the day cause severe dust storms, during which thick clouds of sand and dust rise to heights of 20 km. The composition of the Martian soil was finally revealed during studies of the American Viking 1 and Viking 2 landers. The reddish luster of Mars is caused by the abundance of iron III oxide (ocher) in its surface rocks. The relief of Mars is very interesting. There are dark and light areas here, as on the Moon, but unlike the Moon, on Mars the change in surface color is not associated with a change in altitude: both light and dark areas can be at the same altitude.
Until now, scientists do not know the nature of the cataclysm that caused global climate change on Mars, leading to modern conditions.
Astronomy solution book for grade 11 for lesson No. 13 ( workbook) - Terrestrial planets
1. Using the reference data from the textbook, fill out the table with the main physical characteristics of the terrestrial planets.
| Physical characteristics of planets | Mercury | Venus | Earth | Mars |
| Mass (in Earth masses) | 0.055 | 0.815 | 1 | 0.107 |
| Diameter (in Earth diameters) | 0.382 | 0.949 | 1 | 0.533 |
| Density, kg/m^3 | 5440 | 5240 | 5520 | 3940 |
| Rotation period | 58.6 days | 243 days | 23 h 56 min | 24 hours 37 minutes |
| Atmosphere: pressure, chemical composition | Hardly ever | 95 atm, 96.5% CO(2), 3.5% N(2), etc. | 1 atm, 78% N(2), 21% O(2), etc. | 1/150 atm, 95% CO(2), 2.5% N(2), etc. |
| Surface temperature, °C | +430 during the day; -170 at night | +480 | From +60 to +17 during the day; -80 at night | From +15 to -60 during the day; -120 at night |
| Number of satellites | - | - | 1 | 2 |
| Satellite names | - | - | Moon | Phobos and Deimos |
Fill out the table, draw conclusions and indicate the similarities and differences between the terrestrial planets.
Conclusions: Almost all of the terrestrial planets have identical planes of similar masses. Terrestrial planets, except Mercury, have an atmosphere.
2. The graphs show the dependence of pressure and temperature in the atmosphere of Venus. Answer the questions based on your analysis of the graphs.
At what altitude is the atmospheric pressure of Venus equal to the atmospheric pressure at the surface of the Earth? (Approximately 50 km.)
What is the temperature of Venus's atmosphere at this altitude? (About 330K, or +50 °C.)
3. Using a drawing, describe the internal structure of the Earth.
4. Complete the sentences.
Option 1.
The planet Mercury has the largest difference in day and night surface temperatures.
The high surface temperatures of Venus are due to the greenhouse effect.
A terrestrial planet whose average surface temperature is below 0 °C is Mars.
Most of the surface is covered with water on planet Earth.
The clouds contain droplets of sulfuric acid near the planet Venus.
Option 2.
A planet whose daily surface temperature difference is about 100 °C is Mars.
The planets whose surface temperatures are above +400 °C are Mercury and Venus.
The planet in whose atmosphere global dust storms often occur is Mars.
The planet Mercury has virtually no atmosphere.
The planet with a biosphere is the Earth.
5. Which physical characteristics planets need to be known in order to calculate its average density?
It is necessary to know the mass of the planet and its average radius. The average density is determined by dividing the mass by the volume of the planet.
I once read that in 2024 it is planned to send the first settlers to Mars. Some of my friends expressed a desire to go on this unknown one-way journey. But I don’t really want something, because this planet is lifeless, and I love animals, flowers and wildlife. I especially didn’t want to fly there after watching the movie “The Martian,” which realistically depicted the dull landscapes and unbearable weather conditions of this celestial body. But Mars is our neighbor, it is the second closest planet to us (the first is Venus). There are four planets in the Earth group. They are so called because they consist of solid soil. Let's name them in order of distance from the Sun.
Mercury is the smallest terrestrial planet
A small body characterized by rapid movement around the Sun, for which it received the name god of trade. But Mercury rotates slowly around its axis, so here a day is longer than a year. The atmosphere consists of hydrogen, argon, helium and some oxygen. The climate is hot, temperature - up to +420 degrees.
Venus is the beauty of the terrestrial group
Beautiful When viewed through a telescope or binoculars, it can be seen with the naked eye at dawn. That's probably why she got the name goddess of love. It is characterized by clouds of sulfuric acid that float in carbon dioxide atmosphere. The spectacle is beautiful, but absolutely unsuitable for life. In addition, the temperature on the planet is also goes beyond +400.
Earth is a living planet
This is our planet. Its main feature is life which is possible thanks to:
- atmosphere consisting of air;
- a large number liquid water;
- mild climate.
Ancient people idolized their nurse - the soil, the second name of which is earth. In honor of her, the name of the native planet was given.
Mars is a cold planet
It has red soil, which gave rise to naming him after god of war. Since Mars is located further from the sun's heat than Earth, its climate is very cold. At frost over 130 degrees colonization of the planet is problematic. Yes and atmosphere here is unsuitable for breathing, it consists mainly of carbon dioxide.
Divided into 2 groups based on their planetary surfaces: gas giants and terrestrial planets. Terrestrial planets are characterized by a dense surface and, as a rule, consist of silicate compounds. There are only four such planets in the solar system: Mars, Earth, Venus and Mercury.
Terrestrial planets in the Solar System:
Mercury
Mercury is the smallest of the four Earth-like planets in the Solar System with an equatorial radius of 2439.7 ± 1.0 km. The planet is larger than moons such as Titan. However, Mercury has the second highest density (5427 grams per cubic centimeter) among the planets of the solar system, slightly inferior to Earth in this indicator. High density gives an idea of internal structure planet, which scientists believe is rich in iron. Mercury's core is believed to have the highest iron content of any planet in our system. Astronomers believe that the molten core makes up 55% of the planet's total volume. The outer layer of the iron-rich core is the mantle, which is mainly composed of silicates. The planet's rocky crust reaches 35 km in thickness. Mercury is located at a distance of 0.39 astronomical units from the Sun, which makes it the closest planet to our luminary. Due to its proximity to the Sun, the surface temperature of the planet rises to more than 400º C.
Venus
Venus is Earth's closest neighbor and one of the four terrestrial planets in the solar system. It is the second largest planet in this category with a diameter of 12,092 km; second only to Earth. However, the thick atmosphere of Venus is considered the densest in the solar system, Atmosphere pressure 92 times higher than the atmospheric pressure on our planet. Thick atmosphere consists of carbon dioxide, which has Greenhouse effect and leads to an increase in temperature on the surface of Venus to 462º C, and is . The planet is dominated by volcanic plains, covering about 80% of its surface. Venus also has numerous impact craters, some of which reach a diameter of about 280 km.
Earth
Of the four terrestrial planets, Earth is the largest with an equatorial diameter of 12,756.1 km. She also the only planet from this group, which is known to have a hydrosphere. Earth is the third closest planet to the Sun, located at a distance of about 150 million km (1 astronomical unit) from it. The planet also has the highest density (5.514 grams per cubic centimeter) in the Solar System. Silicate and alumina are the two compounds found in the highest concentrations in the Earth's crust, accounting for 75.4% of the continental crust and 65.1% of the oceanic crust.
Mars
Mars is another terrestrial planet in the Solar System, located farthest from the Sun at a distance of 1.5 astronomical units. The planet has an equatorial radius of 3396.2±0.1 km, making it the second smallest planet in our system. The surface of Mars is mainly composed of basaltic rocks. The planet's crust is quite thick and ranges from 125 km to 40 km in depth.
Dwarf planets
There are other smaller dwarf planets that have some characteristics comparable to terrestrial planets, such as having a dense surface. However, the surface of dwarf planets is formed by a sheet of ice and therefore they do not belong to this group. Examples of dwarf planets in the solar system are Pluto and Ceres.
Characteristics of terrestrial planets
Introduction
Structure of the Solar System
Features of the terrestrial planets
1 Planet Mercury
2 Planet Venus
3 Planet Earth
4 Planet Mars
Conclusion
Introduction
My essay topic is “Characteristics of the terrestrial planets.” The relevance of this work is due to the fact that among the numerous celestial bodies studied by modern astronomy, planets occupy a special place. After all, we all know very well that the Earth on which we live is a planet, so planets are bodies basically similar to our Earth.
But in the world of planets we will not meet even two, absolutely similar friends on each other planets. The variety of physical conditions on planets is very great. The distance of the planet from the Sun, its size, the presence and composition of the atmosphere, the orientation of the axis of rotation, the internal structure and many other properties are different for all nine planets of the Solar System. Major planets are divided into two main groups: terrestrial planets and giant planets. In the abstract we will analyze the terrestrial planets.
The purpose of this work is to analyze scientific data and information on the terrestrial planets.
1. Structure of the Solar System
The solar system is for us, the inhabitants of the Earth, near space.
Every person, at least once in his life, looking at the night sky, asked himself the question: “I wonder what’s next?” After all, the human eye is able to discern only an insignificant part of what the Universe shows us. Everything in the solar system is determined by the Sun, which is the most massive body and the only one with its own glow. By its nature it is a star, the same as those numerous stars that we see in the night sky. It’s just that it’s close to us, that’s why it’s so big and bright.
In general, the sun plays an exceptional role in the solar system. The powerful gravitational field of the Sun holds together all the other bodies of the Solar System - without it they would simply run away, scattered across the vast space. There are currently nine known planets in the Solar System: the four planets closest to the Sun are usually called terrestrial planets, and the next four are called giant planets. The ninth planet, Pluto, the farthest, is not included in any group.
2. Features of the terrestrial planets
The asteroid belt divides the solar system into two parts, which are inhabited by planets that seem completely different at first glance. Closer to the Sun are Mercury, Venus, Earth and Mars. They are called terrestrial planets. These are relatively small balls with a hard surface, surrounded by a not too thick atmosphere. The terrestrial planets are similar to each other in size, mass and rock composition. Their surfaces are composed of hard rocks with an average density of matter from 3.9 g/cm 3on Mars up to 5.5 g/cm 3near the Earth (at Mercury - 5.4 g/cm 3, for Venus - 5.2 g/cm 3). Their main components are silicates (silicon compounds) and iron. The composition of these planets indicates that their growth occurred in the absence of light gases due to rocky particles and bodies containing varying amounts of iron and other metals.
All terrestrial planets have the same structure:
in the very center there is a heavy and hot core. It consists mainly of iron, with an admixture of nickel;
above the core there is a mantle consisting of silicates;
the topmost layer is the crust, formed due to partial melting of the mantle. Therefore, it also consists of silicates enriched with other elements. Only Mercury does not have a crust - it was destroyed by strong meteorite bombardments due to its highly rarefied atmosphere. Earth's crust very different from other planets, with a high granite content.
2.1 Planet Mercury
Characteristics of Mercury:
Weight: 3.3*1023 kg (0.055 Earth mass)
Diameter at the equator: 4880 km
Axis tilt: 0.01°
Density: 5.43 g/cm3
average temperature surfaces: -73°С
Period of rotation around the axis (days): 59 days
Distance from the Sun (average): 0.390 a. e. or 58 million km
Orbital period around the Sun (year): 88 days
Orbital speed: 48 km/s
Orbital eccentricity: e = 0.0206
Orbital inclination to the ecliptic: i = 7°
Satellites: no
The planet Mercury is closest to the Sun. It is the smallest terrestrial planet without satellites located in our solar system. Neither astronauts nor automatic stations have yet visited this small planet. But people know something about it thanks to research from Earth and from the Mariner 10 spacecraft flying nearby (1974-1975). Conditions there are even worse than on the Moon. There is no atmosphere, and the surface temperature averages about 80 0C, and it naturally increases with depth.
However, from time to time the idea was put forward that there could be a planet even closer to the Sun than Mercury. It was precisely this that the German amateur astronomer Heinrich Schwabe was looking for in the 19th century, who discovered (along the way) cycles solar activity. He did not expect to see the planet next to the Sun, but thought that it could be seen as a point on the solar disk when it was between the Earth and the Sun. This is how Mercury and Venus are sometimes seen, located closer to the Sun than the Earth.
Even the period of Mercury's rotation around its axis turned out to be difficult to determine from telescopic observations. And when it was finally determined, it turned out that it was not very much different from the period of the planet’s revolution around the Sun. This situation is completely different from the earthly one. For us, a year is long, but a day is short. The movement of the Earth around the Sun affects the length of the Earth's day, but it is not that significant - by some four minutes per day. On Mercury these periods are comparable, and their combination produces situations that are completely unthinkable on Earth. The fact is that Mercury’s orbit is quite elongated, and, according to Kempler’s laws, the planet moves faster in those areas that are closer to the Sun. And the rotation around the axis is constant, so that at times it lags behind, and at times it advances the effect of rotation around the luminary due to revolution around it.
Traces of volcanic activity can still be noted on the surface of Mercury. These include the so-called scarps - multi-kilometer ledges that arose as a result of shifts of some areas relative to others. The slow rotation of Mercury around its axis leads to the fact that it faces the Sun with the same side for a long time. The average density of Mercury's substance is closer to the Earth's than to the Moon's. This means it has a massive metal core.
The proximity of the Sun causes a noticeable influence on Mercury of the solar wind. Thanks to this proximity, the tidal influence of the Sun on Mercury is also significant, which should lead to the appearance of an electric field above the surface of the planet, the intensity of which can be approximately twice as strong as that of the “clear weather field” above the surface of the Earth, and differs from the latter in comparative stability.
2 Planet Venus
Characteristics of Venus:
Weight: 4.87*1024 kg (0.815 earth)
Diameter at the equator: 12102 km
Axle tilt: 177.36°
Density: 5.24 g/cm3
Average surface temperature: +465°С
Period of rotation around the axis (days): 244 days (retrograde)
Distance from the Sun (average): 0.72 a. e. or 108 million km
Orbital period around the Sun (year): 225 days
Orbital speed: 35 km/s
Orbital eccentricity: e = 0.0068
Orbital inclination to the ecliptic: i = 3.86°
Gravity acceleration: 8.87m/s2
Atmosphere: carbon dioxide(96%), nitrogen (3.4%)
Satellites: no
In Roman mythology, Venus is the goddess of love and beauty. The planet Venus in astrology determines feelings, emotional love, as well as wealth, prosperity, and material happiness. The only things in the sky that are brighter than Venus are the Sun and the Moon.
The planet Venus is Earth's neighbor in the solar system, one of the brightest luminaries in our sky. Since Venus is closer to the Sun than the Earth, we can never see it in the side of the sky opposite the Sun, that is, at midnight on Earth. It is best visible shortly before sunrise or some time after sunset, which gives rise to the name “morning and evening star.” It would seem that since Venus is not far from Earth, you can see a lot of things on it through a telescope. Actually this is not true. On the rather large (in a telescope) disk of Venus, almost no details are visible. Dark spots sometimes appear, but then disappear and appear in other places. In a word, we see not the surface of the planet, but the outer part of its atmosphere.
Further research confirmed that the atmosphere on Venus is indeed “noble.” This expression belongs to Mikhail Vasilyevich Lomonosov, who discovered this atmosphere in 1761 during the passage of Venus across the disk of the Sun (it turned out to be exactly between the Sun and the Earth). When the black dot of Venus was already moving away from the visible solar disk, a light rim (“bump”, in Lomonosov’s words) appeared on its edge. He correctly explained this phenomenon by refraction sun rays in the atmosphere of Venus.
The atmosphere of Venus is very dense. The clouds on Venus never disperse, and if there were any inhabitants on it, they would never see the Sun - although it is one and a half times closer to them than to the inhabitants of the Earth. And the composition of this atmosphere is also exotic: it mainly consists of carbon dioxide, but there is a layer enriched with small droplets of sulfuric acid.
Venus rotates in the opposite direction, that is, the direction of its rotation is opposite to that in which all other planets in the solar system rotate. There are two "continents" on Venus - the Land of Ishtar and the Land of Aphrodite. The most high mountains(up to 11 km above average) are called Maxwell Mountains.
By the way, the English physicist James Clark Maxwell is the only man honored to have a feature of the Venusian surface named after him.
All other names here are traditionally female. The most significant phenomenon on the surface of Venus is manifestations of volcanism. Eruptions leading to the emergence of lava flows are sometimes accompanied by lightning discharges in the atmosphere. And sometimes very viscous lava seems to be squeezed out of the depths, forming characteristic “pancakes”.
There are also traces of meteorite impacts on Venus - craters. But there are fewer of them than on other planets.
The powerful atmosphere provides some protection from cosmic bombardment, and lava flows bury already formed structures.
2.3 Planet Earth
Characteristics of the Earth:
Weight: 5.98*1024 kg
Diameter at the equator: 12,742 km
Axle tilt: 23.5°
Density: 5.52 g/cm3
Surface temperature: -85°C to +70°C
Duration of sidereal day: 23 hours, 56 minutes, 4 seconds
Distance from the Sun (average): 1 a. e. (149.6 million km)
Orbital speed: 29.7 km/s
Orbital period (year): 365.25 days
Orbital eccentricity: e = 0.017
Orbital inclination to the ecliptic: i = 7.25° (to the solar equator)
Gravity acceleration: g = 9.8 m/s2
Satellites: Moon
Planet Earth is the third planet from the Sun in the Solar System, the largest of the terrestrial planets, and is very different in its properties from the other planets in the Solar System. First of all, two thirds of its surface is occupied by water - these are seas and oceans. The remaining part - the land, the continents - is constantly changing. The internal structure of the Earth reflects the course of its development after its formation from clumps of matter rotating around the newly emerged central body - the Sun. The substance that entered the Earth contained little radioactive elements, which, when decaying, released heat. All the substance melted, and its separation began - differentiation. Heavy elements sank to the center and formed the metallic core of the planet. The lungs floated up and froze in the form of the earth's crust - a thin shell no more than 40 km thick. It’s where you and I exist, and it’s where our geologists study it. But the molten substance under the crust - magma - constantly makes itself felt. The earth's crust is, as it were, divided into separate blocks, between which there are cracks (they are called rift zones), and liquid magma penetrates into them. As it rises, it freezes and, as it were, builds up the edges of the continental plates, forcing them to move apart.
There are three outer shells of the Earth: the lithosphere, the hydrosphere and the atmosphere. The lithosphere is understood as the upper solid cover of the planet, which serves as the bed of the ocean, and on the continents coincides with the land. The hydrosphere is underground water, the waters of rivers, lakes, seas and, finally, the World Ocean. solar planet terrestrial mercury
Planet Earth has a unique atmosphere containing oxygen necessary for the life of living organisms. Most of the earth's atmosphere is made up of nitrogen gas. This composition of the atmosphere is not primary; it was formed under the influence of living organisms that arose on Earth.
Essentially, the Earth is a direct current generator.
The Earth's magnetic field arises due to the interaction of rotation around its own axis with the liquid core inside the planet. It forms the magnetic shell of the Earth - the “magnetosphere”.
Magnetic storms- These are sudden changes in the Earth's magnetic field. They are caused by streams of particles of ionized gas that move from the Sun (solar wind), after flares on it. Particles colliding with atoms of the earth's atmosphere form one of the most beautiful natural phenomena- polar lights.
A special glow usually occurs near the North and South Poles, which is why it is also called Northern Lights. Analysis of the structure of ancient rocky formations showed that once every 100,000 years there is an inversion (change) of the Northern and South Pole.
Scientists cannot yet say exactly how this process occurs, but they are struggling to answer this question.
The uniqueness of planet Earth lies in the fact that conditions favorable for organic life have developed on it; this life itself has arisen and exists. Until now, such conditions have not been discovered anywhere in the Universe.
4 Planet Mars
Characteristics of Mars:
Weight: 6.4*1023 kg (0.107 Earth mass)
Diameter at equator: 6794 km (0.53 Earth's diameter)
Axis tilt: 25°
Density: 3.93 g/cm3
Surface temperature: -50°C
Period of rotation around the axis (days): 24 hours 39 minutes 35 seconds
Distance from the Sun (average): 1.53 a. e. = 228 million km
Orbital period around the Sun (year): 687 days
Orbital speed: 24.1 km/s
Orbital eccentricity: e = 0.09
Orbital inclination to the ecliptic: i = 1.85°
Gravity acceleration: 3.7 m/s2
Moons: Phobos and Deimos
Atmosphere: 95% carbon dioxide, 2.7% nitrogen, 1.6% argon, 0.2% oxygen
Ever since it became clear that there are bodies in space that are somewhat similar to our Earth, people have been haunted by the thought of aliens, “brothers in mind.” And the first hope in this regard was Mars. The red planet - Mars - is named after the ancient Roman god of war of the same name, similar to Ares among the Greeks. It is the fourth planet in the solar system in terms of distance from the Sun. It is believed that the blood-red color of the planet, which is given to it by iron oxide, influenced its name.
Mars has always been curious not only to scientists, but ordinary people various professions. Everything from what humanity has laid big hopes to this planet, because most people hoped that life also existed on the surface of Mars. Most science fiction novels are written specifically about the planet Mars.
Trying to penetrate the secrets and unravel its mysteries, people rapidly studied the surface and structure of the planet. But so far we have not been able to get an answer to this question that worries everyone: “is there life on Mars?” The axis of Mars is inclined to the plane of its orbit almost in the same way as the Earth's to its own, so that the seasons change. Mars has an atmosphere. It would seem that all this is encouraging regarding the existence of Martians. But a more careful analysis tells a different story. Mars is almost one and a half times farther from the Sun than Earth, which means that the conditions there are harsher. There is, of course, an atmosphere, but it is already very rarefied: the density at the surface is the same as on Earth at an altitude of more than 30 km. It is known that the lower the pressure, the sooner the water boils. So, at Martian pressure it boils at +2°C. And at zero, naturally, it freezes - liquid water cannot be on the surface of Mars. This is a very serious objection to the existence of life there. And the composition of the atmosphere is more similar to that of Venus than that of Earth: a lot of carbon dioxide and almost no oxygen.
Phobos and Deimos are natural, but very small, satellites of Mars. They have an irregular shape, and according to one version, they are asteroids captured by the gravity of Mars. The satellites of Mars Phobos (fear) and Deimos (horror) are heroes of ancient Greek myths. Both satellites rotate along their axis with the same period, as around Mars, due to this they always face the same side towards the planet. Deimos is gradually being pulled away from Mars, and Phobos, on the contrary, is being attracted even more. But this happens very slowly, therefore, it is unlikely that our next generations will be able to see the fall or complete disintegration of the satellite, or its fall onto the planet.
There are huge extinct volcanoes on the planet. The largest of them is called Olympus and rises 27 km above the surface. There is an amazing branched system of Valley canyons on Mars
Mariners. Meteor craters are also found in abundance. In the mornings, the canyons are shrouded in foggy haze.
The polar caps of Mars are subject to seasonal changes. They are smallest in summer, and then consist almost entirely of water ice. Closer to winter, carbon dioxide from the planet's atmosphere begins to freeze on the cap, and winter caps consist mainly of “dry ice,” known to everyone from ice cream. And in the spring, carbon dioxide evaporates, large masses of gas enter the atmosphere, atmospheric pressure increases near the cap and strong winds begin to blow. Sometimes they raise so much dust and sand that no details on the planet's disk become inseparable from the Earth. There are also dry riverbeds on Mars. Water probably once flowed through them, but they were not rivers in the earthly sense of the word. Suffice it to say that they have no tributaries at all.
But what about traces of life? One of the devices that visited Mars had special program, designed to search for traces of the vital activity of organisms. It was not possible to fully implement it, but from the experiment we can draw the following conclusion: if there is life on Mars, it is only at the level of microorganisms. Hopes for more advanced forms of life are unfounded. And yet the red deserts of Mars are very beautiful...
Conclusion
People's opinions about space can differ radically and even contradict each other. Some argue that it is impossible to know everything about space, others are inclined to believe that humanity will soon learn all the mysteries of the universe. Nowadays, it is known that space is the relatively empty space of the Universe, which is located beyond the boundary of the atmosphere of celestial bodies. But, nevertheless, it contains electromagnetic radiation and low density of hydrogen particles. By the definition of space, our generation understands all space located beyond Earth's atmosphere, including stars and others celestial bodies. By talking about the variety of conditions on the planets, we can gain a deeper understanding of the laws of their development and find out their relationship between certain properties of the planets. So, for example, its ability to retain an atmosphere of one composition or another depends on the size, mass and temperature of a planet, and the presence of an atmosphere, in turn, affects the thermal regime of the planet.
Despite the significant amount of knowledge accumulated by scientists regarding the terrestrial planets, many questions remain to be answered. Decades, and perhaps centuries, will pass scientific research and space expeditions before humanity gets closer to unraveling and scientifically understanding the mysteries of the universe. Practical significance this work is difficult to overestimate.
List of used literature
1. Complete encyclopedia "Cosmos". Edited by V.I. Tsvetkov
Encyclopedia "Science and the Universe". Edited by A.D. Sukhanov and G.S. Khromova
. #"justify">. #"justify">. https://ru.wikipedia.org
Tutoring
Need help studying a topic?
Our specialists will advise or provide tutoring services on topics that interest you.
Submit your application indicating the topic right now to find out about the possibility of obtaining a consultation.