Nine planets and constellations _ The relationship between nine planets and constellations

Who can tell me about the nine planets in the solar system?

The formation of planets

Earth-like planets are formed by the collision and aggregation of solid particles into tiny planets and then aggregation of tiny planets (schematic diagram of the formation of Earth-like planets).

Wood-like planets begin with the mutual adsorption of water and ice. When the mass is large enough, hydrogen and methane are further adsorbed to form gas planets.

Earthlike planets and woody planets

Planets in the solar system can be divided into two categories:

terrestrial planet

Members include Mercury, Venus, Earth and Mars.

It is a small and dense lithosphere with a relatively sparse atmosphere.

Internal structure: there is a gold core in the center, and the outside is surrounded by a stone shell. There are many pits and holes on the surface, and the average density is about 3-5 g/cm3.

Jovian planet

Members are Jupiter, Saturn, Uranus and Neptune.

It is a gas world with large volume and mass, but small density and dense atmosphere. The average density is about ≤ 1.75 g/cm3, the density of the earth star is about 0.7 g/cm3, and the mass of Jupiter is about 3 18 times of the mass of the earth ball.

Structure: From the inside out, there is a rock core, liquid metal hydrogen, liquid molecular hydrogen and a gas layer filled with gas in the center, and a rotating cloud layer on the surface. In addition, there are planetary rings and countless satellite rings around the nine planets in the solar system, with the sun as the center: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. The generation of the stars in the picture shows that they are really relative. The order of the nine planets is often confusing, and the following memory methods may be helpful.

Who is the farthest planet in the solar system?

Since1February 1999 1 1, Pluto has finally become the farthest planet in the solar system. According to the calculation of JPL astronomers, Pluto will be the farthest planet from the sun in 228 years from 9:08 am Universal Time (UT) (Central Plains Standard Time 17:08).

On February 1930, Clyde Tombaugh discovered Pluto while studying the sky photos taken by the telescope of Lowell Observatory. Pluto's cycle around the sun is 248 years, its orbital inclination is about 17 degrees, and its orbital eccentricity is about 0.2480. It is mainly composed of rocks and ice with four distinct seasons. Pluto has only one satellite, Ka Rong, which was discovered in 1978. Since the inclination and eccentricity of Pluto's orbit are much larger than those of other planets, that is to say, some orbits near Pluto's perihelion will fall inside Neptune's orbit (see the attached figure), during the 20 years from1February 7, 979 to1February 999, Pluto was closer to the sun than Neptune.

So will Pluto collide with Neptune in February 1 1? The answer is: no! Why? If Pluto and Neptune want to collide, they must reach the intersection of their orbits at the same time. The rendezvous period between Pluto and Neptune is about 497 years, that is, Pluto orbits the sun twice and Neptune orbits the sun three times. So whenever Pluto passes through the intersection of orbits, Neptune will always go around somewhere else, and the chance of collision is very small. In addition, Pluto's orbital inclination relative to the ecliptic plane is much larger than that of other planets, which is one of the reasons why there will be no collision.

Pluto is about 2300 kilometers in diameter. Of all the planets, it is much smaller than terrestrial planets (water, gold, earth and fire), even smaller than the moon. Its nature is different from that of giant gaseous woody planets (wood, earth, heavenly king, Neptune). The orbital inclination and eccentricity are also much larger than those of other planets. Therefore, some astronomers believe that Pluto should not belong to the "planet" family, but should belong to the "Kuiper Belt". The Cooper Belt lies outside the orbits of Neptune and Pluto. The celestial bodies in the belt are much smaller than Pluto, and most of them are made of ice, which may be fragments of the early evolution of the solar system. But Pluto's shape is spherical and irregular, which is slightly different from these copper belt objects; Moreover, Pluto revolves around the sun regularly, so after many controversies, it is still classified as a "planet" family.

So our understanding of Pluto is very limited. The Jet Propulsion Laboratory (JPL) led by NASA is currently carrying out a project called Pluto? The Pluto-Kuiper Express is scheduled to launch a spacecraft in 2004. In about 10 years, the spacecraft will fly over Pluto and Chalong to explore the celestial bodies in the Cooper Belt.

The orbits of Pluto and Neptune around the sun.

Mercury's little file:

The daily average distance is 579 10000km(0.38 AU).

4,878 kilometers in diameter

Mass 3.30e23

The density is 5.43g/cm.

Gravity 0.376 g

Rotate 87.97 Earth Days.

Rotate 58.65 earth days.

Mercury is the closest planet to the sun. Because it is too close to the sun, the surface temperature is very high, so the spacecraft is not easy to approach, and it is not easy to observe on the earth. Because the observable time is concentrated in a few minutes before the sun comes out in the morning and a few minutes after sunset, it is not easy to grasp the time. And in the case of Shang Gao background brightness, it is not easy to find a mercury that is not much bigger than the moon. Mercury is the closest planet to the sun. Mercury is very small (only Pluto is smaller than it among the nine planets), and it is made of rocks. The surface is covered with craters and potholes formed by meteors, and there are smooth and sparse potholes on the plain. Mercury also has ridges on its surface, which were formed by the gradual cooling and contraction of the planet's core 4 billion years ago, so its surface is uneven. Mercury's rotation speed is very slow, with a rotation of nearly 59 Earth days, so one solar day of Mercury (from sunrise to another sunrise) is almost 176 Earth days-twice that of Mercury's 88 days a year. Mercury's surface temperature varies greatly, reaching 430 degrees Celsius on the sunny side and-170 degrees Celsius on the dark side. When night falls, the temperature drops rapidly because Mercury has almost no atmosphere. The atmospheric composition includes traces of helium and hydrogen captured by the solar wind, and perhaps a little other gases.

Venus's little file:

Average daily distance108,200,000 km (0.72 au).

Diameter 12,103.6km.

Mass 4.869e24

The density is 5.24 g/cm.

Gravity 0.903 g

Rotate 224.7 Earth Days

Rotate 243 earth days

Venus is the second planet in the solar system. The brightest planet in the whole day is Venus, which is usually seen in the morning or evening. At the brightest time, the brightness can exceed -4, just like a street lamp hanging on the hillside, which can be observed by ordinary telescopes, and the profit and loss phenomenon like the moon can often be seen. In the ancient western world, Venus represented the beautiful goddess. Venus is a planet made of rocks and the second farthest planet from the sun. Venus rotates slowly in the opposite direction while revolving around the sun, so its rotation period is the longest in the solar system, which takes about 243 Earth days.

Venus is slightly smaller than the earth, and its internal structure may be similar. Venus is the brightest celestial body in the sky except the sun and the moon, because its atmosphere can strongly reflect sunlight. The main component of the atmosphere is carbon dioxide, which can absorb more heat under the greenhouse effect. Therefore, Venus has become the hottest planet with a surface temperature of 480 degrees Celsius. Thick clouds contain sulfuric acid droplets, which are blown to the earth by the wind at a speed of nearly 360 kilometers per hour. Although Venus takes 243 earth days to rotate once, it only takes 4 earth days for high-speed wind to blow clouds around the planet once. High temperature, acid rain and extremely high atmospheric pressure (about 90 times of the earth's surface) indicate that Venus's environment is harsh.

Earth small file:

Average daily distance149,600,000 km (1.00au).

Diameter12756.3km.

The mass is 5.976e24kg.

The density is 5.52g/cm.

Gravity 1 g (9.8m/s2)

Rotate 365.26 Earth Days

Earth rotation 1 day

The beautiful earth, the miracle of life, is it a coincidence of the universe or a masterpiece of God? The earth is the third planet in the solar system, and there is a satellite called the moon. The protection of the earth's atmosphere and a proper distance from the sun are important conditions for the origin of life.

The earth is the third farthest planet from the sun, the largest diameter and the largest proportion of rocky planet, and the only planet known to have life. The rocks and metals inside the earth show that it is a typical plate. Because the plates are pushed, earthquakes and volcanoes will occur at the junction. The earth's atmosphere and the same protective layer can block harmful radiation from the sun and prevent meteors from hitting the earth's surface. In addition, it can accumulate enough heat to prevent the temperature from dropping sharply. Seventy percent of the earth's surface is surrounded by water, which has not been found on the surface of other planets. The earth has a natural satellite-the moon, which is large enough to regard these two celestial bodies as a two-planet system.

Small files of Mars:

The daily average distance is 227,940,000 km (1.52 au).

6794 kilometers in diameter

Mass 6.4219e23kg

The density is 3.94 g/cm.

Gravity 0.38 g

Rotate 686.98 Earth Days.

Earth rotation 1.026 days

Mars is the fourth planet in the solar system. In the clear night sky, Mars, representing the god of war, shines with fire, attracting the attention of thousands of people in ancient and modern times. One hundred thousand years ago, a rock from Mars fell into the polar region of the earth and was frozen. What people found in this meteorite may be the trace fossils left by life. This fossil was formed on Mars 3 billion years ago. Scientists are actively studying and exploring this planet with mysterious rivers and volcanoes on its surface. Is there life on Mars?

How is life formed?

Mars is usually called the red planet. Mars is the third smallest planet in the solar system, with a diameter of about half of that of the Earth, a volume of about one tenth of that of the Earth, and a surface gravity of about one third of that of the Earth. The atmosphere of Mars is thinner than that of the earth, only 1% of the earth's atmosphere, and the main component is carbon dioxide. There are also some clouds and morning fog. Because the atmosphere is very thin, there is no greenhouse effect on Mars. The temperature near the equator of Mars can reach 27C during the day and drop to-110c at night.

There are many great plains formed by the solidification of volcanic lava in the northern hemisphere of Mars, many craters and large impact basins in the southern hemisphere, several large extinct volcanoes, such as Mount Olympus, which is 600 kilometers wide, and many canyons and bifurcated riverbeds. Canyon is caused by crustal movement, and riverbed is generally considered to be formed by dry rivers. In the high latitudes of Mars, due to the low temperature in winter, carbon dioxide in the atmosphere will freeze, form clouds at a height of 50 kilometers, and disappear in spring. In summer, due to strong sunshine and high ground temperature, the atmosphere near the ground is heated to produce strong updraft. This kind of airflow will roll up the dust on the ground, absorb the heat of the sun in the air, further raise the atmospheric temperature and increase the rising speed, so large-scale rockburst sand can often be seen on Mars.

Mount Olympus, the largest volcano on Mars, is 24 kilometers from the ground, almost three times as high as the highest mountain on earth and the highest mountain in the solar system.

Jupiter's little file:

The average daily distance is 778,330,000 kilometers (5.20 astronomical units).

Diameter142984km (equal)

Mass 1.900e27kg

Density 1.3 1 g/cm.

Gravity 2.34 grams

Revolution 1 1.86 Earth Year

Rotation 0.4 14 Earth Day

Jupiter is the fifth planet in the solar system and the largest planet in the whole solar system. It lies between Mars and Saturn. With an ordinary astronomical telescope (60mm 72 times), you can see the stripes on its surface and four bright satellites. It is the second brightest planet in the whole day, second only to Venus, and the brightness of Jupiter can exceed -2 at the highest. Jupiter is the fifth planet from the sun and the first of four gaseous planets. It is the largest and heaviest planet, its diameter is 1 1 times that of the earth, and its mass is 2.5 times that of the other eight planets combined. Jupiter may have a small stone core surrounded by metallic hydrogen (liquid hydrogen, like metal). The outer surface of the inner mantle is an outer mantle composed of liquid hydrogen and helium, which merge into a gaseous atmosphere. The rapid rotation of Jupiter makes the clouds in the atmosphere form banded and regional stable turbulence to form special clouds such as white spots and red spots, both of which are huge storms. The most famous cloud is a storm called the Great Red Spot, which consists of a spiral cylindrical cloud three times wider than the earth and rises about seven kilometers above the high clouds.

Jupiter has a thin and dark main ring and a thin halo, which is formed by particles extending towards the planet. There are currently 16 satellites. The four largest satellites (called Galileo Io) are Ganybad, Kalis, eo and Europa. There are many potholes on the surface of Ganybad and Callisto, and there may be ice. Europa's surface is slippery, covered with ice and maybe water. There are many bright red, orange and * * spots on Eo surface. These colors come from the sulfur-containing substances of active volcanoes, which are caused by fluffy lava spewing up to hundreds of kilometers from the surface.

The Great Red Spot on Jupiter

The red class is like a huge storm that has been raging for more than 300 years.

This huge oval vortex cloud spans 25,000 kilometers, which is twice that of the Earth and about 40 kilometers higher than other clouds. The top cloud rotates counterclockwise every 6 days. Scientists believe that it is brick red because it contains phosphating substances.

Saturn's little file:

Average daily distance 1, 429,400,000 km (9.54 au).

Diameter120,536 km (equal)

The mass is 5.688e26kg.

The density is 0.69 g/cm.

Gravity 1. 16G

Revolution 29.46 Earth Year

Rotation of 0.436 Earth Days

Saturn is the sixth planet in the solar system and the second largest planet. It has a beautiful ring of light, which can be seen by ordinary telescopes on the earth. Saturn, Jupiter, Uranus and Neptune all have gas on their surfaces, so they all rotate quite fast. Saturn's rings are mainly composed of ice and dust particles. According to scientists' speculation, it may be that a satellite could not stand Saturn's strong gravity and disintegrated into pieces.

Saturn's ring plane and Saturn's revolution plane are not on the same plane, so when Saturn orbits to a certain position, Saturn's ring plane is just parallel to our line of sight, so we can't see this Saturn ring on the earth because it is too thin to be seen from the side. In addition, when Saturn's ring is parallel to the sun, we can't see it because the ring plane is not illuminated.

Saturn, the sixth planet from the sun, is a giant gas planet almost as big as Jupiter, and its equatorial diameter is about 120500 km. Saturn may have a small core made of rocks and ice, surrounded by metallic hydrogen (liquid hydrogen, like metal). Outside the mantle is a mantle composed of liquid hydrogen, which is fused into a gaseous atmosphere.

Saturn's clouds form bands and layers, which are very similar to Jupiter's, but because the outer clouds are thin, they are blurred. Storms and eddies appear in the clouds and look like red or white ellipses.

Saturn has an extremely thin but wide ring system. Although its thickness is less than one kilometer, it extends about 420,000 kilometers from the surface of the planet. The main ring consists of thousands of narrow rings, which are made up of small particles and ice cubes several meters wide. Saturn has 65,438+08 satellites, some of which run in the ring. These satellites exert gravity and affect the shape of the ring. Interestingly, seven of the satellites have a common internal orbit and share the same orbit with other satellites. Astronomers believed that these satellites in common orbit came from the same satellite, but they later broke up.

Uranus' little file:

The daily average distance is 2870990000km( 19438+08 Au).

Diameter 5 1, 1 18km (equal).

Mass 8.686e25

Density1.28g/cm

Gravity 1. 15G

Revolution 84.8 1 earth year

Rotation of 0.72 Earth Days

Uranus is the seventh planet in the solar system. Before the spacecraft arrived, people didn't know that it was also a beautiful ring like Saturn. Uranus is the farthest planet that people can see with the naked eye. However, it is difficult to find Uranus among the stars without professional training. Its biggest feature is its large rotation inclination. Generally speaking, the axis of rotation of a planet is very close to vertical to its revolution surface, but Uranus' axis of rotation is inclined at 98 degrees and runs almost horizontally. Therefore, the sun sometimes shines on the North Pole all day, while the southern hemisphere is dark all day. Uranus emits blue-green light and its surface is white, so it is speculated that its atmosphere may contain a lot of methane. On the other hand, Uranus is about four times the diameter and fourteen times the mass of the earth, but its density is less than a quarter of that of the earth. This is because Uranus, like other Jupiter types, is mainly composed of gases such as hydrogen and helium.

Uranus also has nine rings above the equator. Together, these nine rings are about100000 km wide, which is about one third of the width of Saturn's rings. The structure and composition of Uranus rings are very different from those of Saturn and Jupiter. Saturn's rings are made up of thousands of rings with narrow gaps, while Uranus' nine rings are far away from each other. Among the nine rings, the inner eighth ring is about 10 kilometers wide and the outermost ring is more than 100 kilometers wide.

Neptune's little file:

The average daily distance is 4.504 billion kilometers (30.06 astronomical units).

49,528 km in diameter (equal)

Mass 1.0247E26kg

Neptune is the eighth planet in the solar system, with eight satellites. Neptune's surface is mainly composed of gas, and there is a great red spot storm cloud similar to Jupiter's surface, which we call the great black spot. This big storm is about half of Jupiter's Great Red Spot, but it can also accommodate the whole earth. Neptune is also like Saturn's ring, but this ring is smaller than Uranus.

Jupiter's rings and Saturn's rings made of ice particles look very bright, but Uranus' bamboo rings are made of carbon particles or rock particles, so they are very dim. Neptune and Pluto are the two planets farthest from the sun, with an average distance of 4.5 billion kilometers and 5.9 billion kilometers respectively. Neptune is a huge gas planet with a small stone core surrounded by a mixture of liquid and gas. Clouds in the atmosphere have obvious characteristics, the most obvious of which are big black spots, as wide as the earth, and small black spots and scooters. Black spots, large and small, are huge storms, sweeping the world at a speed of 2000 kilometers per hour. Sukeda is a large cirrus cloud. Neptune has four thin rings and eight satellites. Triton is the largest satellite of Neptune and the coldest star in the solar system, with a temperature of MINUS 235 degrees Celsius. Unlike most satellites in the solar system, Triton's orbit around its parent planet is opposite to Neptune's rotation.

Neptune's four narrow and dark rings are caused by dust particles produced by the violent impact of tiny meteorites on Neptune's satellite.

Pluto's little file:

The daily average distance is 59 13520000km(39.5 AU).

2340 kilometers in diameter

Mass 1.32e2kg

The density is 2.03g/cm.

Gravity?

Revolution 247.7 Earth Year

The earth rotates for 6.39 days

Pluto is the ninth planet and the last planet in the solar system. Pluto is too far and too small, smaller than our moon, more than 13 thousand times farther than the moon, so that the best optical astronomical telescope can't see its surface clearly. Unless the spacecraft can get close, the mystery of Pluto cannot be solved. At present, it is only known that Pluto has a satellite. Whether there are other planets besides Pluto is something that scientists are studying. There is only indirect evidence that our solar system seems to be the tenth planet, but more and more evidence shows that there are no other planets besides Neptune, and there may be a large number of small stars outside Neptune, which are called Cooper belt objects. Pluto may also be one of them. Pluto is usually the farthest and smallest planet from the sun, but because of its elliptical orbit, it will cross Neptune for 20 years in its 248-year period of revolution. However, Pluto's revolution plane and the ecliptic plane are inclined at 17 degrees, so there is no possibility of collision. Pluto is small and far away, and our understanding of it is limited. It is a rocky planet whose surface may be covered with ice and frozen methane.

Information provided: Chen Junqiang

Stars, nine planetary satellites, meteorite constellation black hole