The nature of the terrestrial planets presentation. Characteristics of terrestrial planets
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 indicate 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's 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).
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 the presence of lightning.
The sky on Venus is a bright yellow-green hue.
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.
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.
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.
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 visited by humans.
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.
Planet Mercury. This is the planet closest to the Sun (Fig. 56). Named after the ancient Roman god of trade. Mercury is similar in size and mass to the Moon. He also resembles her in appearance. On the surface of this planet there are mountains and craters, like on the Moon.
Craters are rounded depressions 100-200 km wide and several kilometers deep. Since Mercury is close to the Sun (58 million km), its surface heats up to 400 °C. Mercury rotates very slowly around its axis - a day on it is about 176 Earth days, and a year lasts only 88 days.
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| Rice. 57. Venus |
Planet Venus named after the ancient Roman goddess of love and beauty (Fig. 57). In the sky it shines brighter than the stars and is clearly visible to the naked eye. Venus is smaller in size than Earth and has a dense cloudy atmosphere consisting mainly of carbon dioxide. This allows heat to be retained, so the temperature on Venus is even higher than on Mercury. The surface of Venus is mostly plains with low hills, but there are mountainous areas and even a huge volcano 12 km high. A year on Venus is 224.7 Earth days, and a day is almost 117 times longer than on Earth.
Planet Earth- the largest planet of the terrestrial group and the only one with an air envelope (Fig. 58). The air envelope of the planet is called the atmosphere. It consists primarily of nitrogen, oxygen and carbon dioxide. More than 70% of the Earth's surface is covered with water. The presence of atmosphere, water, and moderate temperature create ideal conditions for the existence of life on planet Earth. Other planets do not have such conditions.
The Earth rotates around the Sun in 365.3 days, and a day is 24 hours long. Material from the site
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| Rice. 59. Mars |
The planet Mars- the fourth planet of the Solar system (Fig. 59). Named after the ancient Roman god of war. The surface of Mars is rich in iron, which is why the planet has a red color. Mars is half the size of Earth. The atmosphere of Mars consists predominantly of carbon dioxide. The average temperature on the surface is -70 °C and only at the equator rises slightly above 0 °C. The surface of the planet is deserts, craters, mountains. Some of them are quite tall. For example, the height of the extinct Olympus volcano is 27 km. A year on Mars is 1.9 Earth years, and the length of a day is 24 hours 39 minutes.
TERRESTRIAL PLANETS
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 is the closest planet to the Sun.
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 located close to the Sun.
Mercury's maximum elongation is only 28 degrees.
therefore it is very difficult to observe.
Transit of Mercury across the solar disk
The best photos of Mercury from Earth
In size, Mercury can be compared with large
satellites of other planets in the solar system
Comparative sizes of Mercury and other celestial bodies
The surface of Mercury in photographs taken from close up
distances, replete with craters (photos by Mariner 10 spacecraft)
Degas Crater
Surface of Mercury
Computer processing
photographs of the surface of Mercury
Copley Crater
There are fewer dark formations - seas - on Mercury than on the Moon
Computer processing of photographs of the surface of Mercury from the Mariner 10 spacecraft.
The light stripe at the top means there are no photographs of this area.
There are many craters on the surface of Mercury
Surface area of the Northern Hemisphere
Mercury is about 500 km wide
Smooth, rounded plains were discovered on the surface of the planet,
named after their resemblance to the lunar “seas” swimming pools .
The huge Caloris pool (left),
reaching a diameter of 1300 km,
has a strong resemblance to circular
seas on the Moon.
It was probably formed as a result
collision of Mercury with a large
celestial body at an early stage
geological history of Mercury.
The pool is the result of the outflow
lava from the bowels of the planet after a collision.
The planet revolves around the Sun in 88 Earth days.
A solar day on Mercury lasts 176 Earth days.
those. exactly 2 Mercury years.
earthly years and months
The average speed of Mercury's orbit is 47.9 km/s.
Quickly rushing along its orbit, Mercury lazily turns around its axis.
Day and night last 88 days, i.e. equal to the year of the planet.
Mercury's rotation axis is almost perpendicular to the orbital plane.
The change of seasons on Mercury is not caused by the tilt of the axis,
and by changing the distance to the Sun.
Data on the atmosphere of Mercury indicate only its strong rarefaction.
The pressure at the surface of the planet is 500 billion times less than at the surface of the Earth (this is less than in modern vacuum installations on Earth).
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.
Chemical composition of Mercury's atmosphere
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.
The average radius of the planet is 6051 km
Planet mass – 4.8675 · 10 24 kg (0.815 Earth masses)
The average distance of Venus from the Sun is 108 million km (0.723 AU). The distance from Venus to Earth varies from 38 to 261 million km. Its orbit is very close to circular - the eccentricity is only 0.0067.
The period of revolution (Venus year) around the Sun is 224.7 Earth days; average orbital speed - 35 km/s. The inclination of the orbit to the ecliptic plane is 3.4°.
Rotation period (Venus day) - 243.023±0.002 days
Atmosphere Venus consists mainly of carbon dioxide (96%) and nitrogen (almost 4%). Water vapor and oxygen are contained in it in trace quantities.
average temperature+ 467 C (Venus is the hottest planet in the solar system), atmospheric pressure is about 93 atm. .
The inclination of Venus's axis to the plane of its orbit is close to a right angle, so there is no change of seasons on it, and it is always and everywhere very hot. Since 1967, Soviet automatic stations have been lowered into the atmosphere of Venus. These were the world's first soft descents of automatic equipment onto the surface of another planet with radio transmission of information from it to Earth.
Automatic station "Venera-10"
Surface of Venus
A detailed map was compiled by the American Magellan spacecraft, which photographed 98% of the planet’s surface. Mapping has revealed extensive elevations on Venus. The largest of them are the Land of Ishtar and the Land of Aphrodite, comparable in size to the earth's continents. Numerous craters. They probably formed when Venus's atmosphere was less dense. A significant part of the planet's surface is geologically young (about 500 million years old). 90% of the planet's surface is covered basalt lava.
Internal structure.
Several models of the internal structure of Venus have been proposed. According to the most realistic of them, Venus has three shells. The first crust is approximately 16 km thick. Next is the mantle, a silicate shell that extends to a depth of about 3300 ﾊ km to the boundary with the iron core, the mass of which is about a quarter of the total mass of the planet. Since the planet’s own magnetic field is absent, it should be assumed that in the iron core there is no movement of charged particles of electric current causing a magnetic field, therefore, there is no movement of matter in the core, that is, it is in a solid state. The density in the center of the planet reaches 14 g/cm³.
Exploring the planet using spacecraft
Venus has been studied quite intensively using spacecraft. The first spacecraft intended to study Venus was the Soviet Venera-1. After an attempt to reach Venus with this device launched 12th of February 1961 , Soviet spacecraft of the “Venera”, “Vega” series, and the American “Mariner”, “Pioneer-Venera-1”, “Pioneer-Venera-2”, “Magellan” were heading towards the planet. IN 1975 the Venera-9 and Venera-10 spacecraft transmitted the first photographs of the surface of Venus to Earth; V 1982 “ ” and “Venera-14” transmitted color images from the surface of Venus. However, the conditions on the surface of Venus are such that none of the spacecraft worked here for more than two hours.
View from Earth.
Venus is easy to recognize because it is much brighter than the brightest stars. A distinctive feature of the planet is its smooth white color. Venus, like Mercury, does not move very far from the Sun in the sky. At moments of elongation, Venus can move away from our star by a maximum of 48｡. Like Mercury, Venus has periods of morning and evening visibility: in ancient times it was believed that morning and evening Venus were different stars. Venus is the third brightest object in our sky
Venus is a candidate for terraforming. According to one of the plans, it was planned to spray genetically modified blue-green algae, which, by processing carbon dioxide(the atmosphere of Venus is 96 ﾊ% carbon dioxide) in oxygen, would significantly reduce Greenhouse effect and would lower the temperature on the planet.
Terraforming Venus
However for photosynthesis the presence of water is necessary, which, according to the latest data, is practically absent on Venus (even in the form of vapor in the atmosphere). Therefore, to implement such a project, it is necessary first of all to deliver water to Venus, for example, by bombarding it with water-ammonia asteroids or in another way. It should be noted that at an altitude of ~ 50 - 100 km in the atmosphere of Venus there are conditions under which some terrestrial bacteria .
Mars is the fourth from the Sun and the seventh largest planet in the Solar System.
Planet's distance from the Sun: 227,940,000 km (1.52 AU) from the Sun
Equatorial radius: 3396.2 km (0.532 Earth)
Weight: 6.4219 · 10 23 kg ( 0.107 earth)
Circulation period (length of year) 686.98 Earth days 1.8808476 Earth years.
Rotation period (length of day)
24 hours 39 minutes 35.244 seconds (24.6597 h)
Orbital speed – 24.13 km/s
Axis tilt - 251919 0
According to NASA (2004), the atmosphere of Mars consists of 95.32% carbon dioxide; it also contains 2.7% nitrogen, 1.6% argon, 0.13% oxygen, 210 ppm water vapor, 0.08% carbon monoxide, nitrogen oxide (NO) - 100 ppm, neon (Ne) - 2, 5 ppm, semi-heavy water hydrogen-deuterium-oxygen (HDO) 0.85 ppm, krypton (Kr) 0.3 ppm, xenon (Xe) - 0.08 ppm (composition is given in volume fractions).
Atmosphere of Mars
The pressure at the surface of Mars is 160 times less than on Earth - 6.1 mbar. Due to the large difference in altitude on Mars, the pressure at the surface varies greatly. Maximum value 8.4 mbar. is reached in the Hellas Basin (4 km below average surface level), and at the top of Mount Olympus (27 km above average level) it is only 0.5 mbar. Unlike Earth, the mass of the Martian atmosphere varies greatly throughout the year due to melting and freezing of the polar caps containing carbon dioxide.
The climate, like on Earth, is seasonal. The angle of inclination of Mars to the orbital plane is almost equal to that of Earth and is 25.1919°; Accordingly, on Mars, just like on Earth, there is a change of seasons.
According to NASA (2004), the average temperature is ~210 K (−63 °C). According to data from the Viking landers, the daily temperature range is from 184 K to 242 K (−89 to −31 °C) (Viking-1), and the wind speed is 2-7 m/s (summer), 5 -10 m/s (autumn), 17-30 m/s (dust storm).
Researchers from the Carl Sagan Center in 2007-2008 came to the conclusion that in recent decades there has been a warming process on Mars. In May 2016, researchers from the Southwest Research Institute in Boulder (Colorado) presented new evidence of ongoing climate warming.
Surface topography
The elevation differences are quite significant and amount to approximately 14-16 km in the equatorial region, but there are also peaks that rise much higher, for example, Arsia (19 km) and Olympus (21.2 km) in the elevated Tarais region in the northern hemisphere. Observations of Mars from satellites reveal clear traces of volcanism and tectonic activity - faults, gorges with branching canyons, some of them are hundreds of kilometers long, tens of them wide and several kilometers deep. The most extensive of the faults - “Valley Marineris” - near the equator stretches for 4000 km with a width of up to 120 km and a depth of 4-5 km.
Craters
The large number of craters in the southern hemisphere suggests that the surface here is ancient - 3-4 billion years old. Several types of craters can be distinguished: large craters with a flat bottom, smaller and younger bowl-shaped craters similar to the Moon, craters surrounded by ridges, and elevated craters. The last two types are unique to Mars - rimmed craters formed where liquid ejecta flowed across the surface, and raised craters formed where a blanket of crater ejecta protected the surface from wind erosion.
There really is water on Mars
And if earlier scientists were content with guesses, now everything has been confirmed chemically.
The photo taken by Mars Express shows the region Echus Chasma (Canyon of Echoes), which contains the largest reserves of water on Mars.
The Phoenix probe confirmed the presence of water on Mars. The presence of water was shown by analyzes of rock samples that Phoenix obtained with the help of his manipulator.
A sample of Martian soil in which water was discovered was retrieved by Phoenix from approximately a five-centimeter depth of the Red Planet. The device loaded the frozen soil into a miniature laboratory furnace, and to the delight of the scientists, steam began to emerge from there.
"We have discovered the nutrients needed to support life - past, present or future," said Sam Kounaves, a chemist at the University of Arizona. He noted that there are no harmful substances in the soil of Mars. “This type of soil is most likely alkaline in your garden,” the scientist said. “It’s very good for growing asparagus.”
Topographic map of Mars
Telescopic studies of Mars have revealed features such as seasonal changes in its surface. This primarily applies to the “white polar caps,” which begin to increase with the onset of autumn (in the corresponding hemisphere), and in the spring they “melt” quite noticeably, with “warming waves” spreading from the poles. A significant part of the surface of Mars consists of lighter areas (“continents”) that have a reddish-orange color; 25% of the surface is darker “seas” of gray-green color, the level of which is lower than that of the “continents”.
Moons of Mars
Orbit radius
Circulation period
Average radius
26.8 × 22.4 × 18.4 km
15 × 12.2 × 10.4 km
Thanks to the Mars Express station
The mystery of the “Martian Sphinx” was solved.
The high-resolution photo shows that it is simply a high hill, washed away by erosion.
Astronomy lesson “Structure of the solar system” Teacher: Babenkova Z.S. Municipal educational institution "Rumyantsevskaya secondary school".
solar system
Terrestrial planets
Mercury Mass - 0.055 Earth masses Rotation period - 58.8 days Temperature - during the day - +430, -170 at night
Venus Mass -0.816 Earth masses Rotation period - 243 days Temperature - + 480 Atmosphere - 96.5% carbon dioxide, 3.5 nitrogen
Earth Mass - 1 (in Earth masses) Rotation period - 23 hours 56 minutes Atmosphere - 78% nitrogen, 21% oxygen, etc. Number of satellites - 1 Temperature - + 60 - + 17, - 80 at night.
MARS Rotation period 24 hours 37 minutes. The atmosphere is 95% carbon dioxide, 2.5% nitrogen. Mass - 0.107 mass Temperature - +15 to -60, -120 at night. 2 satellites - Phobos, Deimos.
Giant planets
Jupiter Mass - 318 Earth masses Rotation period - 9 hours 35 minutes. The atmosphere is 89% hydrogen, 11% helium. The number of satellites is 63.
Saturn Mass - 95 Earth masses Rotation period - 10 hours 37 minutes. Temperature - -170 Atmosphere - 94% H, 6% He. The number of satellites is 35.
Uranium Mass - 14.6 Earth masses Rotation period - 17 hours 14 minutes. Temperature - 217 Atmosphere - 83% H, 15% He, 2% methane. The number of satellites is 27.
Neptune Mass - 17.7 Earth masses Rotation period - 16 hours 07 minutes. Temperature -214. Atmosphere - 84% H, 15% He, 1% methane. The number of satellites is 13.
Pluto Mass - 0.0022 Earth masses Temperature - -230. The rotation period is 247.7 years. Is this planet or asteroid???
Complete the sentences A planet whose daily surface temperature difference is 100 degrees... A planet in whose atmosphere dust storms often occur..... A planet with a biosphere - The planet has practically no atmosphere.....
Preview:
Municipal educational institution "Rumyantsevskaya Secondary School"
Open lesson on astronomy
in 11th grade
TERRESTRIAL PLANETS
Teacher Babenkova Zinaida Sergeevna
TERRESTRIAL PLANETS
TARGET: consider issues of the physical nature of the terrestrial planets.
LEARNING OBJECTIVES:
A) general education –formation of concepts about the basic physical characteristics of the terrestrial planets;
b) developing – developing the ability to analyze information;
V) educational –formation of the scientific worldview of students during their acquaintance with the history of the study and nature of the terrestrial planets; development of students' ecological thinking.
STUDENTS SHOULD KNOW:
main characteristics of planets as a class of cosmic bodies;
structure and physical characteristics of the Earth;
physical characteristics and distinctive features of the terrestrial planets - movement, mass, size and density (in comparison with terrestrial ones), internal structure, relief, physical conditions on the surface and features of origin.
STUDENTS SHOULD BE ABLE TO:
use reference data from astronomical calendars for observing celestial bodies.
LESSON PLAN
Summing up the lesson. Homework |
Stage I
During a frontal survey, students answer questions (if difficulties arise, you can use reference data from the textbook).
The planet is orbiting at its closest distance from the Sun Mercury.
The planet comes to its closest distance to Earth Venus.
The planet has the shortest period of revolution around the Sun among the giant planets Jupiter.
The largest terrestrial planet in size is Earth .
The planet has the largest mass Jupiter.
The planet has the closest mass to the mass of the Earth Venus.
The planet has the highest average density Earth .
The fastest planet rotates around its axis Jupiter.
Have no planetary satellites Mercury and Venus.
10. Terrestrial planets include Mercury, Venus, Earth, Mars.
Stage II
Having reminded students of the basic information about the structure of the Solar system, it is necessary to note the special role of planets as celestial bodies on which life is possible. For many years, the source of knowledge about the planets has been visual, photographic, photometric and spectral observations. Currently, the data from these observations have been significantly refined and supplemented thanks to radio astronomical observations and research using spacecraft.
Students need to be explained that the main physical characteristics of planets are mass, size, average density, and speed of rotation around their axis. Also important here are the average density and chemical composition of the atmosphere, the angle of inclination of the planet’s axis to the density of its orbit, the distance from the Sun, and the number of satellites. It is according to their basic physical characteristics that planets are divided into two groups.
The study of the terrestrial planets can begin with a brief overview of basic information about the lithosphere, hydrosphere, atmosphere and magnetosphere of the Earth, and then move on to the characteristics of each of the planets. A more clear presentation of the material can be carried out by parallel consideration of the same characteristics for all planets. Here it is important not only to report ready-made data, but also to indicate the methods by which this data was obtained. Students should clearly know the physical characteristics of the Earth, such as its size (average radius), mass and average density. Other planets are considered based on comparison with Earth.
Only the very thin (6-10 km) upper layer of the earth's lithosphere is accessible to direct study of the internal structure of the Earth. The main method for studying deeper (than is accessible by drilling wells) layers of the Earth's lithosphere is seismic research. During earthquakes or explosions, seismic waves arise in the body of the Earth, which, having experienced refraction and reflection in the bowels of the planet, are recorded by seismographs at various points on the earth's surface. The speed of wave propagation depends on the density and elastic properties of the medium in which they propagate. Research has made it possible to identify two main parts in the structure of the Earth's interior: the solid shell - the mantle, and the liquid core, located deeper than 3 thousand km. At the very center of the Earth there is an inner core similar to a solid body, formed under the influence of enormous pressure.
In addition to the material presented in the textbook, students should be taught about the heat balance of the Earth. Over the billions of years of our planet's existence, an equilibrium has been established in which the Earth emits into space the same amount of energy as it receives from the Sun. Energy emission occurs predominantly in the infrared (thermal) wavelength range, which is actively absorbed by molecules of water vapor and carbon dioxide. Therefore, even minor fluctuations in the concentration of these gases in the atmosphere have a huge impact on the Earth’s heat balance and climate formation. Thanks to the so-called greenhouse effect, the average temperature of the Earth is 40 0 C above the effective temperature due to the flow of solar energy and thermal radiation from the Earth. Without the greenhouse effect in the atmosphere, the temperature on the Earth's surface would be about -24 0 And life would become impossible. The greenhouse effect smoothes out daily temperature drops of up to 15 0 C.
In this lesson, you can additionally (for propaedeutic purposes) familiarize students with the role of the Earth’s magnetosphere and the scheme of formation of radiation belts. If the Earth did not have a magnetosphere, cosmic radiation would kill all life on it. However, most of the cosmic rays are deflected by the Earth's magnetic field, and some are captured, and only the most energetic particles reach the upper layers of the atmosphere, mainly in the region of the Earth's poles, and cause the glow of rarefied gases - auroras. Material about the magnetic field and radiation belts of the Earth is closely related to the problems of solar-terrestrial connections.
Photographs, drawings and other visual aids demonstrated during the lesson will allow students to imagine the comparative sizes of the planets, the features of their rotation around their axes, etc. You should not get carried away with using numerous numerical data in the lesson; in this case, working with reference tables will be more effective.
In this lesson, a number of questions can be linked to environmental issues of the Earth. When considering the atmospheres of the terrestrial planets, students should pay attention to the formation of the cloud cover of Venus. The study of clouds on Venus is not only of great scientific, but also practical interest in connection with the problem of protecting the environment from pollution on Earth. The fact is that Venusian fog is similar in a number of properties to terrestrial smog fogs caused by industrial and transport emissions into the atmosphere. Earthly smog, which disrupts the ecological balance and causes many undesirable consequences, arises as a result of the accumulation of sulfur dioxide in the air, which, when oxidized, forms droplets of sulfuric acid. Under the influence of solar radiation, such fog does not dissipate, but even thickens. By understanding the complex processes that occur in the clouds of Venus, scientists can contribute to solving the problem of protecting the Earth's atmospheric air from pollution.
In connection with the increasing proportion of carbon dioxide in the earth's atmosphere, questions about the role of the greenhouse effect for the earth's atmosphere are currently being discussed. In this case, elucidating the evolution of the greenhouse effect, weather and climate on Venus is of great importance. Since weather-forming processes on Venus are not as complex as on Earth, studying a simpler Venusian model of weather and climate may be useful for solving problems in terrestrial meteorology. You can draw students' attention to one feature: almost all the details of the relief of Venus bear female names. The plains are named after mythological characters (Mermaids, Snow Maidens, Baba Yaga), large craters - in honor of prominent women, and small ones - with personal female names.
Mars is the only planet where global dust storms are observed. Martian dust storms are similar to those on Earth in a number of respects. Therefore, their study is of great importance.
Introducing students to information about the evolution of the terrestrial planets will contribute to the formation of general scientific concepts about the knowability of the world, the unity of the laws of physics for the entire Universe, the interconnection and interdependence of natural phenomena.
The evolution of Mercury was determined by its proximity to the Sun and the low mass of the planet. The surface of Mercury was heated by the rays of a nearby star and by explosions during collisions with small planetesimals. Apparently, Mercury was the first of the fully formed planets. The earliest stages of the evolution of Venus, its internal structure and chemical composition, are probably similar to those on Earth, but later the paths of their development diverged greatly. The evolution of Mars was determined by the small mass of the planet and its distance from the Sun. The gravitational differentiation of matter was not as deep and complete as that of other terrestrial planets.
To reinforce the lesson material, students are given a task that they can complete using the textbook.
Complete the sentences.
Option 1.
The largest difference in day and night surface temperatures on the planet Mercury.
The high surface temperature of Venus is due togreenhouse effect.
A terrestrial planet with an average surface temperature below 0 0 C is Mars.
Most of the planet's surface is covered with water Earth .
The clouds contain droplets of sulfuric acid near the planet Venus.
Option 2.
A planet whose daily surface temperature difference is about 100 0 C is Mars.
Planets whose surface temperatures are above +400 0 C is Mercury and Venus.
A planet in whose atmosphere frequent global dust storms occur is Mars.
Virtually no planetary atmosphere Mercury and Pluto.
A planet with a biosphere is Earth .
Stage III
When doing homework, students fill out the following table with the main physical characteristics of the terrestrial planets:
Mercury is the closest planet to the Sun. 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.
The surface of Mercury in photographs taken at close range is replete with craters (photos by the Mariner 10 spacecraft) Degas Crater Copley Crater Surface of Mercury Computer processing of photographs of the surface of Mercury
The vast Caloris Basin (left), reaching 1,300 km in diameter, bears a strong resemblance to the circular seas on the Moon. It was probably formed by the collision of Mercury with a large celestial body early in Mercury's geological history. The pool is the result of lava flowing out of the planet's interior after a collision. On the surface of the planet, smooth rounded plains were discovered, which were called basins due to their resemblance to the lunar “seas”.
Mercury makes two revolutions around the Sun in the same time, during which it manages to turn around its axis three times. A solar day on Mercury lasts 176 Earth days, i.e. exactly 2 Mercury years. The average speed of Mercury's orbit is 47.9 km/s. Quickly rushing along its orbit, Mercury lazily turns around its axis. Day and night last 88 days, i.e. equal to the year of the planet. earthly years and months
Chemical composition of the atmosphere of Mercury Data on the atmosphere of Mercury indicates only its strong rarefaction. The pressure at the surface of the planet is 500 billion times less than at the surface of the Earth (this is less than in modern vacuum installations on Earth). 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. The radius of the core is 1800 km (75% of the radius of the planet). 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.
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. Maximum surface temperature of Mercury recorded by sensors, °C. Temperature differences on the day side due to the change of seasons caused by the elongation of the orbit reach 100 °C.
