The problem of the eight planets

I. Mercury:

Basic parameters of mercury:

Half-length diameter of orbit: 57,965,438+00,000 kilometers (0.38 astronomical unit)

Period of revolution: 87.70 days.

Average orbital speed: 47.89 km/s.

Track eccentricity: 0.206

Track inclination: 7.0 degrees

Planet equatorial radius: 2440 km

Mass (Earth mass = 1): 0.0553

Density: 5.43g/cm3

Rotation period: 58.65 days

Number of satellites: None

Mercury is the closest planet to the sun, and its angular distance from the sun never exceeds 28. In ancient China, Mercury was called the morning star, while in the west, it was called Mercury. Mercury (Hermes) was a special messenger in Roman mythology who sent messages to the gods. He has great magic and walks like a fly. Mercury does move as fast as mercury. It is the fastest planet in the solar system.

Mercury is dense, second only to the earth among the nine planets. It may have a dense core rich in iron. Mercury's landform is similar to the moon, with craters of different sizes scattered all over the place, as well as radiation patterns, plains, rifts, basins and other landforms. Mercury's atmosphere is very thin, and the temperature difference between day and night is very large. The temperature under direct sunlight is as high as 427℃ and drops to-173℃ at night.

Until the 1960s, it was thought that the time for Mercury to rotate once was the same as that for Mercury to revolve once.

So the side facing the sun is constant. This is similar to the fact that the moon always faces the earth with the same half face. But in 1965

In, with the help of the world's largest radio telescope at Arecibo Observatory in the United States, the frequency between the reflected waves at the two edges of Mercury was measured.

Poor, successfully measured the rotation period of Mercury is 58.65 days, which is exactly 2/3 of that of period of revolution.

Two Venus:

Basic parameters of Venus:

Half-length diameter of orbit:10.82 million kilometers (0.72 astronomical unit)

Period of revolution: 224.70 days.

Average orbital speed: 35.03 km/s.

Track eccentricity: 0.007

Track inclination: 3.4 degrees

Planet equatorial radius: 6052 km.

Mass (Earth mass = 1): 0.8 150.

Density: 5.24 g/cm3

Rotation period: 243.0 1 day.

Number of satellites: None

Besides the sun and the moon, Venus is the brightest star in the sky. At its maximum brightness, it is 14 times brighter than Sirius, the brightest star in the whole day. China called it Taibai in ancient times, and the Romans called it Venus, the goddess of love and beauty.

Venus and the sun have a maximum viewing angle of no more than 48 degrees on the earth, so Venus will not appear in the night sky all night. In our country, people call Venus at dawn the morning star and Venus at dusk the evening star. Venus rotates slower than revolution, but in the opposite direction, so the year on Venus is getting shorter and shorter. The sun seen on Venus rises in the west and sets in the east.

Venus is sometimes called the sister star of the earth. On the outside, Venus and the Earth have many similarities. Venus's radius is only 300 kilometers smaller than that of the earth, its mass is 4/5 of that of the earth, and its average density is slightly smaller than that of the earth. Some people speculate that the physical condition and chemical composition of the surface of Venus will be similar to that of the Earth, and there will also be an environment suitable for life. However, it turns out that the surface temperature of Venus is extremely high enough to melt lead and tin, and it is difficult for any life to survive. Venus and the earth are just sisters.

The density of the atmosphere on Venus is 100 times that of the earth, and more than 97% of the atmosphere is carbon dioxide.

There is also a thick cloud of concentrated sulfuric acid with a thickness of 20-30 kilometers. Clouds of carbon dioxide and concentrated sulfuric acid make the heat on the surface of Venus unable to

The enclosed solar radiation emitted into space makes the surface of Venus hotter and hotter, and the temperature on the surface of Venus is the highest.

Up to 447℃. This is the so-called greenhouse effect. The atmospheric pressure of Venus is 90 standard atmospheric pressure (equivalent to the ocean on the earth).

1 km) The deep pressure, whether you have steel or iron, will be crushed to pieces when you reach Venus.

III Mars and its moons:

Basic parameters of Mars:

Half-length diameter of orbit: 227.94 million kilometers (1.52 astronomical unit)

Period of revolution: 686.98 days.

Average orbital speed: 24.13km/s.

Track eccentricity: 0.093

Track inclination: 1.8 degrees.

Earth's equatorial radius: 3398 kilometers

Mass (Earth mass = 1): 0. 1074.

Density: 3.94 g/cm3

Rotation period: 1.026 days.

Number of satellites: 2

Among terrestrial planets, Mars is a red planet, which was called "Huo Ling" in ancient China and regarded as "Mars myth" in ancient Roman mythology in the west. Mars is also the most legendary planet. After the invention of the telescope, Mars was once called "the small earth in the sky" because it was observed that its various characteristics were similar to those of the earth. Exciting topics such as "the life of Martians" and "Martians" have been around for nearly a century.

In fact, Mars is not as beautiful as people think. Its surface is desolate everywhere. 75% of the surface is a desert composed of iron oxides such as silicate and limonite, which is an orange-red and brown-red Gobi scene. The atmosphere of Mars is thin and dry, and there is almost no water. The main component is carbon dioxide, accounting for about 95%. The noon temperature near the equator is about 20℃, and the temperature difference between day and night is above 100℃. The so-called "polar cap" at the poles of Mars is not ice formed by water, but dry ice solidified by carbon dioxide.

The length of a day on mars is almost the same as that on earth; There are four seasons on Mars because the axis inclination is similar to that of the Earth. When the earth and Mars run to the same side of the sun and are almost in a straight line, it is said that Mars rushes to the sun. Because of the large eccentricity of the elliptical orbit of Mars, there is an impact that is particularly close to the earth every 15- 17 years, which is the best time to observe Mars.

In order to explore the secrets of Mars, more than 20 probes have been launched for scientific exploration of Mars in the past 30 years. These tests

The robot took thousands of photos and collected a large number of Martian soil samples for inspection. The experimental results so far show that fire

There are no rivers, lakes and oceans on the star, no traces of animals, plants or microorganisms in the soil, and no intelligent life such as "Martians"

Existence.

Mars satellite:

Mars has two small satellites, named respectively.

Phobos and Demos. he

The child is the son of the god of war, flying in the sky in a chariot.

List of firefighters:

2) Giant planets with rings:

Jupiter and Saturn are giant planets in the planetary world, called giant planets. They have a dense atmosphere, but there is no solid surface under the atmosphere, but a "Wang Yang Sea" composed of boiling hydrogen. So they are essentially liquid planets.

I Jupiter and its moons:

Basic parameters of Jupiter:

Half-length diameter of orbit: 778.33 million kilometers (5.20 astronomical units)

Period of revolution: 4332.7 1 day.

Average orbital speed: 13.6 km/s

Track eccentricity: 0.048

Track inclination: 1.3 degrees.

Equatorial radius of the planet: 71398km.

Mass (Earth mass = 1): 3 17.833.

Density:1.33g/cm3

Rotation period: 0.4 1 day

Number of satellites: 16

Jupiter is second only to Venus in brightness. In ancient China, it was used to determine the year, so it was called the "year star". In the west, Jupiter is called "Jupiter", the king of the gods in Roman mythology. Jupiter is indeed the king of the nine planets. Its mass is 2.5 times that of the other eight planets in the solar system combined, which is equivalent to 3 18 times that of the earth.

Jupiter has no solid shell and is a sea of liquid hydrogen in a dense atmosphere. Jupiter

Its interior is a solid core composed of iron and silicon, called Jupiter core, and the temperature is as high as 30000℃. wood

Outside the core is Jupiter's mantle made of liquid hydrogen. Further away is Jupiter's atmosphere. Jupiter

The thickness of the atmosphere is more than 1000 km, and it is composed of 90% hydrogen, 10% helium and trace methane, water,

Ammonia, etc. Although Jupiter is huge, its rotation speed is the fastest in the solar system.

The rotation period is 9 hours, 50 minutes and 30 seconds, nearly two and a half times faster than the earth. Such a rapid rotation

It has caused very complicated atmospheric movements on Jupiter's surface, and all kinds of convection and circulation movements are very intense.

And there are many layers of cloud belts parallel to the equator. Even more bizarre, Jupiter also exists in the southern hemisphere.

The great cyclone that has been moving for hundreds of years is called the Great Red Spot. It's big enough to hold.

Several earths, colorful clouds are moving violently, and some are similar to dragons on the earth.

tornado

1979, voyager probes 1 and 2 found that Jupiter has rings similar to Saturn. But Jupiter's rings and the earth

The starlight ring is very different. Jupiter's halo is diffuse, consisting of three parts: bright ring, dark ring and halo. The bright ring is outside the dark ring,

Halo is a very thin dust cloud, which surrounds the bright ring and the dark ring. Jupiter's ring is about 128000 km from Jupiter's center, and the ring

It is more than 9000 kilometers wide and only a few kilometers thick. It consists of a lot of dust and dark gravel, which is difficult to see with the naked eye.

On the huge Jupiter body, it is not easy to find dim and thin Jupiter rings.

Jupiter's moons:

Jupiter is a planet with a large number of satellites in the solar system. At present,

16 satellites have been discovered. Jupiter's moons were first discovered.

After the sequence number, the first four digits are the largest and the most.

This bright satellite was first discovered by Galileo with a telescope, so later generations

Named Galileo satellite.

Io list:

II Saturn and its moons:

Basic parameters of Saturn:

Half-length diameter of orbit: 65,438+0,429,400,000 kilometers (9.54 astronomical units)

Period of revolution: 10759.5 days.

Average orbital speed: 9.64 km/s.

Track eccentricity: 0.056

Track inclination: 2.5 degrees

Earth's equatorial radius: 60330 km

Mass (Earth mass = 1): 95. 159.

Density: 0.7 g/cm3

Rotation period: 0.426 days

Number of satellites: 18

Saturn is a beautiful planet, second only to Jupiter in mass and size. In ancient China, Saturn was called the town star. In the west, people named Saturn after the Roman god of agriculture.

Saturn and Jupiter are like twin brothers, and they have many similarities. Saturn also has a core made of rocks. The core is surrounded by a shell made of 5000 km thick ice and metallic hydrogen, and the outside is also wrapped in a thick color layer like Jupiter, mainly composed of hydrogen and helium. There are dense ammonia crystal clouds floating in the atmosphere, and there are also vortex structures similar to Jupiter's Great Red Spot-white spots, but on a smaller scale. If Jupiter's atmospheric movement is complicated, then Saturn's atmospheric movement is relatively calm and simple.

Saturn's period of revolution is slow, it takes 29.5 years to orbit the sun once, and its rotation period is 10 hour 14 minute. Because of its rapid rotation, Saturn is actually a very flat sphere. Its equatorial radius is over 6000m, and the difference is almost equal to that of radius of the earth.

Although Saturn is huge, its average density is only 0.7 g/cm3, which is the smallest of the nine planets and lighter than water.

Saturn's rings stand out in the telescope. This halo is actually composed of countless small ice cubes with a diameter between 7 cm and 9 m. The structure of the halo is extremely complicated, and they are colorful under the sunlight. Voyager once made a survey of Saturn's rings.

Close observation shows that the overall shape of Saturn's rings is like a huge compact record, from the top of Saturn's clouds to the top.

External extension. Saturn's rings are usually divided into seven layers. The D ring is closest to Saturn and has the darkest brightness, followed by the C ring.

The transparency is the highest, the B ring is the brightest, and then the A ring. There is a dark and wide seam between the A ring and the B ring, which is famous.

Cassini's circumferential seam. There are three rings outside the A ring: F, G and E, and the E ring is at the outermost layer, which is very thin and wide.

Saturn's moons:

There are many satellites around Saturn, of which 18 has been confirmed. that

Titan is the largest in China, with a radius larger than that of Mercury. It is also called "Tai"

Tan ",that is, the female giant god in Greek mythology. Titan is also a satellite of the solar system.

The only celestial body with a dense atmosphere is nitrogen, accounting for about

98%, the thickness of the atmosphere is about 2700 kilometers.

Titan list:

3) distant planets:

Uranus, Neptune and Pluto, three distant planets, are called distant planets, which were discovered only after the invention of the telescope. They have an atmosphere mainly composed of molecular hydrogen, usually covered with a very thick layer of ice, such as methane ice and ammonia ice, and then a hard rock core.

Uranus and its moons:

Uranus basic parameters:

Half-length diameter of orbit: 28,709,900 kilometers (19808 astronomical unit).

Period of revolution: 30685 days.

Average orbital speed: 6.8 1 km/s.

Track eccentricity: 0.046

Track inclination: 0.8 degrees

Equatorial radius of the planet: 25,400km.

Mass (Earth mass = 1): 14.5.

Density: 1.3g/cm3

Rotation period: 0.426 days

Number of satellites: 20

Uranus ranks seventh in the sun in the solar system. In the west, it is named Uranus, the god who rules the whole universe in Greek mythology. Uranus is 65 times the size of the earth, second only to Jupiter and Saturn, and is the third largest planet in the solar system. Its radius is four times that of the earth, and its mass is about 14.5 times that of the earth.

One of the uniqueness of Uranus is the way it rotates. Basically, other planets move with their rotation axes close to the revolution plane, but Uranus' rotation axis has an inclination of 98 degrees and almost lies around the sun.

The main components in Uranus atmosphere are hydrogen (83%), helium (15%) and methane (2%). Under the thick atmosphere is the Wang Yang Sea, which is 8000 kilometers deep, which is surprisingly higher than its temperature, nearly 4000℃, and higher than the temperature of molten steel in the steelmaking furnace.

Uranus also has a halo, which was discovered when observing the eclipse of Uranus in 1977. Uranus * * * has

1 1 ring, different rings have different colors, adding new luster to this distant planet.

The moon of Uranus:

Uranus has confirmed that there are 20 satellites, including several new discoveries, but

This unnamed satellite has the largest number of satellites among the nine planets.

This planet.