A brief overview of the bright moon

The moon

The moon, also known as "the moon". Before the invention of the telescope, ancient people could only look up at the bright moon on a clear night. Seeing that the surface of the moon is bright or dark and has a strange shape, people will compile the beauty myth of the moon, the Wu Gang of cutting osmanthus, and the free pounding of jade medicine. The ancient Greeks regarded the moon as a beautiful goddess of hunting, Artemis, and the goddess of hunting with a silver bow as an astronomical symbol of the moon.

There is basically no water in the world's moon, and there is no weathering, oxidation and corrosion process on the earth. There is no sound transmission and it is full of silence. The moon itself does not emit light, the sky is always dark, and the sun and stars can appear.

The moon has almost no atmosphere, so there is a temperature difference between day and night on the moon. During the day, when exposed to vertical sunlight, the temperature is as high as 127.25°C, and at night the temperature can be as low as -183.75°C. Since there is no atmospheric barrier, the intensity of sunlight on the moon's surface is about 1/3 that on the earth, and the intensity of ultraviolet rays is much stronger than that on the earth. Earth's surface. In the lunar atmosphere, many strange phenomena will be seen on the lunar surface. For example, the moon in the sky is dark black, direct sunlight shines brightly, and there are very dark protected areas. You will see how bright or dark the moon's surface is. Without air to scatter light, the moon and stars no longer appear to twinkle.

Outlines of exposed rock and craters on the moon's surface. The entire lunar surface is covered with a layer of dust on the surface of gravel particles. Light and dark gray areas from the Earth to the Moon's surface. The original bright parts of the lunar surface are the mountains and highlands, and the plains and dark gray parts of the lunar surface.

The diameter of the moon is 3476 kilometers larger than that of the earth, which is equivalent to 3/11 of the diameter of the earth. The surface area of ??the moon is about 1/7-14 of the earth's surface, which is slightly smaller than the sub-area; its volume is 1/49 of the earth, in other words, it can fit 49 of the earth under the moon. The moon's mass is 1/81 of the earth's, and its average density is 3.34 grams per cubic centimeter, which is only equivalent to 3/5 of the earth's density. The gravity on the moon is only 1/6 of the earth. In other words, only 1 kilogram of something 6 kilograms reaches the limit on the moon. Walking on the lunar surface, the body seems very relaxed and it is a bit difficult to leap. The astronauts run and jump for half of the lower part of the lunar surface. It seems that they are so happy walking on the earth.

The moon is the closest celestial body to the earth. It is the only natural satellite orbiting the earth, with an average distance of about 384,400 kilometers from the earth. The Moon's orbit around the Earth is a random circular orbit, with the average distance of perigee (from the Earth) being 363,300 kilometers and the average distance of the apogee (farthest from the Earth) being 405,500 kilometers, a difference of 42,200 kilometers.

Like the Earth, the moon's north and south poles are slightly flattened, and its equator is slightly higher and flattened. Its average polar radius is smaller than the equatorial radius of 500 meters, the asymmetric bulge of the North Pole and the South Pole, and the Arctic depression of about 400 meters.

As the moon orbits the earth, it also moves with the earth around the sun. This means that the moon orbits the earth once and then returns to a position in space that is not the original starting point. Therefore, the moon also participates in a variety of movements and is systematically involved in the movement. In the motion of the moon and other celestial bodies, the moon is a perpetual motion machine. The moon rises in the east and sets in the west, and it also moves an average of more than 13° relative to the stars in one day from west to east. The moon rises every day, not about 50 minutes later the day before. Rising and setting in the east, the moon is a reflection of the earth's rotation; moving from west to east is the result of the moon's orbit around the earth. The moon's orbit around the Earth is called a sidereal month, which lasts on average 27 days, 7 hours, 43 minutes, and 11 seconds. At the same time that the moon is revolutionizing near the Earth, it is also spinning. The moon's rotation period and revolution period are equal, that is, 1:1. The time it takes the moon to orbit the earth is its rotation period.

This peculiar rotating moon: the moon always faces the earth, and the same half of the moon can never be seen. The back of the moon is only open to detectors from the earth. The eternal mystery of the moon was reached as early as 30 years ago human desires.

Today's large telescopes can distinguish targets about 50 meters (equivalent to 14 stories high) on the lunar surface.

The moon has many interesting laudatory names in ancient Chinese poetry: jade free (free intentional castle Zhanyu, screen cover, silver palace - Xin Qiji); luminous (luminous virtue, death and infertility? - Qu Yuan) Su'e (Su'e Moon Talks to the Other Side - "Young School Qionglin"); Moon (Jade Hook Collection, Moon Hanging Wuzhe - Lu You); Moon (Moon Rolls with Dew, Wet and Heavy Light on Guixiang Street, Luan Chuan Encounters - Li); Yu Chan (Cool) At night, Sanwu Jade Toad Qiu Liujing - Qianbian); Gui Po (Gui Po flying to illuminate the cold day dip blue - Su Shi); Toad (Min Guo sailed towards the toad and lost a complex group - Jia Dao); Gu Tu ( The male bird does not come out of the valley, Gu Tu is half-hiding - Li Bai), the moon (May people live long, thousands of miles away from Chan Juan - Su Shi). In addition, the moon also has many unique nicknames, jade bow, jade osmanthus, jade plate, etc. Jade Hook, Jade Mirror, Ice Mirror, Guanghan Palace, Chang'an, Jade Sheep.

Preliminary Mystery of the Moon

gt; The moon is the closest celestial body to the earth at a distance of 38,400,000 kilometers. Astronomers used telescopes to observe the moon's terrain, and they knew the moon's terrain very well. The moon was full of mountains and fields, with countless small craters and ravines, but there was also a lack of water and air on the moon, and the temperature difference between day and night was huge, dead and desolate. The telescope can tell the target of 50 meters, but it is still not as clear as the field inspection, so the first celestial body sent by human messengers still chose the moon.

The first lunar probe was launched in 1958. On January 18, 1959, the first-stage rocket exploded during launch and died midway. Afterwards, the launch of three Pioneer spacecrafts was unsuccessful. On January 2, 1959, the former Soviet Union launched a spacecraft to the moon, flying smoothly on the road. On April 1, 7,500 kilometers away from the lunar surface, it unfortunately did not hit the moon. This probe weighed 361.3 kilograms and became the first artificial planet nine months later with the most advanced communication and detection equipment. deep space. Two months after the launch of the moon, on March 3, the Pioneer 4 spacecraft launched by the United States flew from a distance of 59,000 kilometers to the lunar surface, but did not impact the moon.

Lunar spacecraft from 1958 to 1976 In 2006, the former Soviet Union launched 24 lunar spacecrafts, 18 of which completed their missions to explore the moon. It was launched on September 12, 1959. It flew to the moon two days later and landed hard on the Chenghai Sea on the lunar surface, becoming the first person to reach the moon. A messenger, the first flight from the earth to another celestial body. It contained a radio communication device in the scientific instrument cabin that stopped working after impacting the moon. On October 4, the same year, the lunar spacecraft arrived at the moon and wrapped around the back three days later. The moon took the first distant photo of the moon, allowing people to see the face of the moon for the first time. The world's first lunar soft landing probe was launched on January 31, 1966 after 79. During the hour-long flight, it landed near the Moon's Oceanus Procellarum and took photos of the lunar surface. The probe weighed 1,583 kilograms and reached 75 kilometers from the lunar surface. The 100-kilogram lander separated from the probe body and landed slowly by relying on an automatic robot installed outside. Inflated balloon. The moon launched on September 12, 1970, and made a soft landing on the lunar surface using a drill for the first time to collect rock samples from a 120-gram mouth-sealed container and returned to Earth on November 10, 1970, carrying the world's first An automatic lunar rover landed on the lunar surface on Mare Imbrium on Moon 17, 17, 2009. The lunar rover went to the lunar surface on 10 and a half months of scientific exploration on the recovery module. The lunar rover weighs 756 kilograms, is 2.2 meters long and 1.6 meters wide, and is equipped with a television camera and nuclear energy device. Traveled 10,540 meters on the Moon and surveyed 80 million square meters of surface area, took 200 lunar panoramic photos and over 20,000 lunar surface photos, ceased operations until October 4, 1971, when nuclear power was exhausted, January 1973 Launched to the moon on the 8th and 21st, the lunar rover sent inspection results to the lunar surface.

Drilling holes and rock samples were finally launched on August 9, 1976. The Moon 24 spacecraft made a dangerous sea soft landing on the lunar surface on August 18, bringing back 170 grams. At this time, the Soviet Union's unmanned detection of the moon declared it complete, and a richer understanding of the moon was complete.

Wandering, Surveyor Probes

After the former Soviet Union, the United States has launched nine Ranger and seven Surveyor lunar probes. The "Prowler" probe looks like a dragonfly, 3 meters long, with solar panels on its wings spread to 4.75 meters, detection equipment installed in the front, and a TV camera on the tail. The Surveyor probe had three legs, a total weight of 1 ton, and was equipped with state-of-the-art inspection equipment. The first five "Prowler" probes had no success until the launch of "6 Prowler" on January 30, 1964. The TV camera failed to land on the surface of the moon and failed to take any photos. On July 28, the same year, the lunar rover surface, sea? Close-up photos of the cloud landing face were taken to 4308, and then wandered, launched on February 17, 1965, and Ranger 9, launched on March 24, successfully landed on the moon and took 7137 5814 close-up photos of the lunar surface. The new probe Surveyor was launched on May 30, 1966. After a 64-hour flight, Ocean Storm made a soft landing on the lunar surface back to 11,150 lunar surface photos. Seven Surveyors, a probe launched on January 1, 1968, failed successfully in two of the five. Later, the United States launched five lunar orbits to select the landing site for the Apollo manned lunar landing detection data. After this series of unparalleled Manned probe, the true face of the moon is revealed

For the first time since July 16, the 1969 Apollo 11 spacecraft manned the moon, based on the results of several lunar explorations, and brought back the moon Rocks, soil analysis, and humans on the lunar surface learn more. Scientists believe that the foreign moon is rockier than the Earth but is also the oldest, and that the moon and the Earth are composed of almost the same chemical elements but different compositions. For example, moon rocks contain higher levels of calcium and aluminum than rocks on Earth. There is no magnetic field on the moon, and its crust is relatively stable with little change over the past 3 billion years, although astronomers have long believed that the moon is petite. The body, weak gravity (1/6 of the Earth), does not have the ability to match the high temperature of the sunny side of the atmosphere, and the gas molecules will easily reach escape velocity and escape. Moon measurements show that there is no atmosphere in the uninvited country on the surface of the moon, but the atmosphere is too thin, the atmospheric pressure on the surface is 2×10" bar, and the composition of the atmosphere is more complex, and changes in time and space usually occur in At night, when the atmosphere is composed mainly of 40% argon and 40% neon, and 20% helium, a very small amount of methane and ammonia are also added to the sunrise, and are also found in the atmosphere in certain areas A very small amount of hydrogen, radon, sodium, polonium and potassium atoms American scientists recently claimed the existence of ice on the moon, which may be the drinking water of thousands of people exploring the moon, and the ice can also be broken down into hydrogen and oxygen. Rocket fuel.

It was found from on-site inspections that there are more than 300,000 craters scattered around the moon. The largest crater is nearly 300 kilometers in diameter and 6,000 meters above sea level. Spectacular. Unfortunately, since there is no water on the moon, these mountains are bare, barren, and desolate. Apparently, in order to make this desert moon world a suitable paradise for biological survival, it eventually became a vibrant place where everything could survive. , Flower Paradise Earth, the top priority is to solve the water supply problem on the moon. Over the years, scientists have proposed various ideas, and there is one solution: mining the moon's storage capacity for extremely rich iron oxide, smelting it in a solar smelting furnace, The moon and space make synthetic water the best solution possible in principle, releasing a large amount of oxygen, and transporting spacecraft to collect liquid hydrogen from space to combine to generate water for the development of the moon. However, the implementation of this huge plan is not yet planned. Easily, a range of problems related to energy, mining, transportation, and life need support to be solved.

pgt; Most attractive to humans, the lunar soil contains large amounts of gaseous helium-3, which is far less deuterated than the radioactive material currently used in nuclear materials on Earth. Helium-3 originally abounds in the radioactive raw materials spewed out by nuclear power plants. Yes, in the sun's high-energy particles (solar wind), there is almost no atmosphere on the moon. The "solar wind" landing directly drags down the passage of time. The sand and rocks on the moon's surface collect about 1 million tons of this material. If it is mined in large quantities, not only The energy required for the development of the moon also provides inexhaustible nuclear energy raw materials for the earth's nuclear fusion in the 21st century.

The maximum temperature of the moon during the day and night can reach 127°C. The temperature at night is as low as minus 183 degrees. The climate is so hot and cold, and the temperature difference is drastic. There is no sign of human habitation and life in the moon for half a year. This is another important reason why Russian scientists use the soil on the moon to produce cement and other building materials. Rocks are then used to build a base that can adjust the room temperature, making it suitable for long-term research on human habitation. Based on the analysis of measurement data, it is believed that the moon is likely to be a hollow sphere. One day, you can make a passage on the surface of the moon and enter the underground palace of the moon deep in the moon's crust, where you can build an "underground city" suitable for human habitation. Visitors can fly to the moon in a spacecraft and spend the night in this underground city hotel. Science And technical workers can explore lunar resources, aerospace products, astronomical observations and other activities based on this underground city. The permanent base of the underground moon palace is not yet completed. Scientists suggest that it can be made of prefabricated mold components on the earth, and a huge cylindrical automatic vertical l Pre-assembled, with the operator of the Cosmos on the lunar surface, the cylindrical surface of the lunar surface was automatically divided into two open halves and automatically formed a multi-story structure of the building, the temporary accommodation for the lunar debut "volunteers".

(SAN)

2. The birth of the moon

The mystery of the birth of the moon

How was the moon originally formed? This is a very controversial issue in the scientific community, and there are about three theories

Captive "theory": Some scientists believe that the moon was originally a meteor that sometimes entered the specific gravity range when flying loosely in space. Limited by gravity, it accidentally entered the Earth's orbit, but in recent years, many people have cited celestial mechanics to oppose this theory

The "split" theory: Scientists hold this view that the moon. It was split from the hot wind rotating clouds surrounding the earth, so the moon is a "child" of the earth. It was brought back several times by the "Apollo" spacecraft. However, the results show that the composition of the moon and the earth are very different.

Collision theory: This theory holds that about 4.5 billion years ago, the Earth was larger than Mars and suddenly flew at a speed of 4,000 kilometers per hour. It struck the early Earth with such intensity that the iron core of the planet struck all the way to the center of our planet. The result of the collision was a huge explosion, accompanied by temperatures of 6,000 degrees Celsius. The Earth exploded out of shape, and the greatest celestial body took a "suicide" to integrate with the Earth. Only part of the turbulent jets of hot steam and other debris into space, and later the steam cooled and solidified into dust, dust and other debris. Mixed together to form a core, this examination condensed our neighbor - the gray moon was born.

Scientists have used a new supercomputer to simulate the occurrence of a strange collision in space to test the theory.

New Origins of the Moon

Where did the moon come from? This is a new theory that people are constantly exploring. In recent years, with the rapid development of modern computer technology and the theory of earth evolution, a new theory of the origin of the moon is called the new catcher theory.

Look at the origin of the moon and planetary evolution

In recent years, based on the modern theory of planetary evolution, scientists have used computers to calculate the initial stages of the formation of the solar system, between The force acting on the sun, the earth, and the moon gave rise to the theory of acquiring a new moon. Scientists believe that the moon formed in the early days of the earth, and was captured in the earth's interior by the gravity of the earth. At the time of this new theory, this phenomenon was a very common phenomenon. , said the so-called new catcher.

The old and new captures are different. The old man said that considering the origin of the moon, the gravity of the earth can only be studied from the planet formation process of the entire solar system and the new origin of the moon. The nine major planets and satellites of the new solar system, including the moon, originated from the primitive solar nebula 4.6 billion years ago. The primitive solar nebula contained solid particles and formed a thin disk-shaped nebula around it. Its own gravity gradually gathers on the equatorial surface of a large number of particle nebulae to form a thin layer of solid particles. As the particle density increases, its stability will be destroyed to a certain extent and it will be crushed into small celestial bodies with a radius of 5 kilometers. , asteroids The entire solar system was originally about one trillion asteroids. Countless asteroids orbited the sun in the nebula gas. They collided with each other and gradually grew up. Our planet, planets of different sizes were formed like this. There are about 1 billion Years ago, they grew into such a large

planetary nebula gas covering a planetary nebula with a strong cloud surrounding the early childhood growth of the Earth. The gas was called the primitive atmosphere, especially at that time, it was intense The solar wind with strong solar activity gradually blew away the original atmosphere, and later the original atmosphere surrounding the earth gradually became thinner and drifted closed

The moon originated from the original solar nebula, and its evolution was roughly the same as that of the earth. The moon first appeared on the earth. When we reach adulthood, the original atmosphere begins to escape and fly close to the earth's gravitational circle, thus becoming a prisoner of the earth.

The gravitational circle of the moon to the earth exerts a lot of force to stay in the satellite orbit. There are four main forces capturing the moon, the earth, the tidal force of the sun's gravity and the resistance gravity field of the original atmosphere.

Under normal circumstances, celestial bodies with the greatest gravity fly into the Earth's gravitational circle, including the Moon. However, only small celestial bodies captured by the Earth's gravitational field follow an elliptical orbit. The gravity field of the earth and the sun's gravity, the orbit of small groups has been changed by the earth's gravitational pull, the gravitational circle orbit of the sun to the earth is not completely elliptical, and will inevitably run away from the gravity of the circle after flying for several weeks, Cannot stay in satellite orbit.

However, the moon did not escape from the earth's gravitational circle, which is due to the resistance of the original atmosphere at work. The earth's gravity sharply brakes the resistance from the moon to the moon, and part of the energy is lost. The orbital radius of the original atmosphere is smaller, and they cannot escape.

That being said, due to the atmospheric drag, the orbital radius of the moon is getting smaller and smaller. Will it fall into the earth sooner or later and collide with the earth? Don't worry, when the moon flies into the earth's gravity ring, the original atmosphere has begun to be gradually released into the atmosphere. The moon suffers increased atmospheric drag. After the original atmosphere disappears, the moon suffers the resistance and disappears, so the orbit radius is smaller. It will not collide with the earth

After the atmospheric resistance disappears, the power of tides is at work. Tidal forces in the Moon's orbit speed up the orbit, intensify the effect of centrifugal forces, but extinguish it. It is reported that by observing the lunar orbit radius, in fact, it increases by about 3 centimeters every year.

Under the above 4 forces, the moon is captured and neither falls to the ground nor de-gravity cycle and always runs in the satellite orbit, accompanying it on the earth for a long time.

Capture is a common phenomenon

The capture of small objects by planets is a common phenomenon in the process of planetary evolution. This phenomenon is not only found in the solar system of the Earth and other planets.

Many planets have their own satellites. The Earth is the best in the formation process. Many small celestial bodies have flown into the gravitational circle. Part of the small group has directly collided with the Earth. Most of the rest are flying around the Earth because of the strong gravitational force. The orbital radius of the original atmospheric drag was small, and it finally fell to the earth. The original earth continued to "swallow" and flew up

The moon was captured later than other small celestial bodies. The moon was the final cohesion of the earth, and in the early days When the original atmosphere of the Moon was captured in the first 10-100 years, and other small bodies were captured, the orbital radius also decreased, but after the original atmosphere disappeared, the Moon's orbital radius changed, and the Moon's subsequent centrifugal tendency made it It survived and the Earth "swallowed" French scientist F. Miguel told me that the trend of the moon's capture orbit has been calculated. As shown in the calculation results, from the drawings, it can be seen that the distance between the moon and the earth was just taken, and the moon's orbit was close to the earth after tens of millions of years. The radius is 35 times, 60 times, and 20 times the radius of the Earth in 10 billion years. 46 billion years later, it is where it is now.

Due to the captured moon, the Earth almost never captures other small groups. The moon is already orbiting the earth. If there are other small objects flying in accordance with the principles of celestial mechanics, instead of being in a stable state, it will not fall into the earth and fly out and will not fall into the moon. The Earth's moon is accompanied by a satellite.

Capture is a common phenomenon among all real planets in our solar system, with the exception of Venus. Venus's rotation speed is very slow, rotating once every 250 days or so. It cannot be captured on this planet and still roams the world alone in the sky.

After capturing and clarifying the origin of the moon's evolution from the entire planet and being captured, explaining this issue in the origin of the moon is the most authoritative theory. However, this new theory also has some further research issues, such as , the ability to capture satellites without raw atmospheric drag? What is the difference between prograde and retrograde satellite photos? After repeated studies, scientists will surely have a correct and comprehensive understanding of the origin of human beings on the earth.

(Science and Technology Information Center of the China Association for Science and Technology)

Protoplanet collision with the Earth and the Moon

The results published in the "Nature" magazine in 16 days were used by scientists to simulate the formation of During the course of the moon, according to their model, the moon was born less than 100 million years after the sun was born 4.6 billion years ago, and a Mars-sized object hit the earth to create a dark object no larger than the earth. Halfway through the orbit, the original planet met the Earth, hit the Earth, and the Earth rotated around its own axis. Perot, a researcher who modeled the model, described the thrilling process: Viewed from the side, from the outer layer of the Earth The impact and unnamed impact tore away parts of the material, about half of which formed the Moon. The torn material was heated to unimaginable levels, evaporated and expanded

Several mysteries of the moon

The origin of the moon: Human mysteries about the origin of the moon, ***three Assuming that the moon was captured by the earth - the homology of the moon says that the earth split apart. There is no strong evidence for the three hypotheses, leading to the fourth hypothesis "Moon"

The mystery of the age of the moon: Analysis of rock samples brought back from the moon to determine the age of the moon found that compared to 90% of the most Ancient rocks, moon rocks are 99% older. A 1973 World Symposium has measured the age of a lunar rock on the moon to be 5.3 billion years old, while the oldest rock on Earth is 3.7 billion years old. Some scientists believe that the moon formed in interstellar space long before the Earth was formed.

In addition, there is the mystery of the formation of craters on the moon. The age of the lunar soil is much older than the rocks. The mystery of the impact of the larger moon. The mysterious impact of the moon is not rusty. Iron Plenty of Water, the Mysterious Gas on the Dry Moon.

Second, there is a large amount of literature. The moon has not existed since ancient times.

●The ancient American Mayans left behind a very developed culture, but before the "Three Duo", they began to overflow. , it is surprising to find that there is no record about the moon

●About 4,000 years ago, the first librarian of the Library of Alexandria wrote in the documents he left: "In ancient times , the moon cannot be seen in the sky of the earth

●Historical astronomy records a shocking information: Taizong Tianhui Yichou, suddenly disconnected from the south in the 10th year of the 15th year, was complicated. Therefore, "it means: in the eleventh year of Taizong's reign (AD 1133), in May (the sixth day of June), Yi Chou (15th), the moon suddenly deviated from its orbit to the south, and after a while, it returned to its original orbit.

3. Myths and legends related to the moon

●Chinese mythology about the moon was first recorded in the song "Huainanzi" in the "Book of Mountains and Seas" and other ancient books.

● Moon, folklore and mythology, including the story of the moon, Zhu Yuanzhang's uprising against Yuan Shikai cycle.

●It is said that the moon has a laurel tree five hundred feet high. During the Han Dynasty, a man named Wu Gang, who was obsessed with mystery instead of focusing on his own research, was exiled to the moon to cut laurel trees, and the osmanthus cut together with his descendants, so that they could see Wu Gang cutting down 5 laurel trees in the endless forest. Image BR pgt ;Ancient Chinese fantasy poems about the moon

●The virtue of luminous light, death and disinfection? What's the use of jueli when the rabbit is in the stomach? (Qu Yuan Chu Ci·Tianwen)

(Meaning: What is the moon? Has it died naturally when we have grown up? What are the benefits of taking care of a child held by a rabbit?)

agt;

●Seal with laurel in the middle of the moon, clear light (Du Fu's "150 late one month")●The sky where old rabbits and cold toads weep, the half-open wall of the cloud building is slanted, the white jade wheel is calendered and dews wet quality, Luan Pei gathered in Guixiang Street. (Li He's "Dream Sky")

●It's only a month away from Jinxi, where is it? No need to ask, can you only see light and shadow to the east? The sky and the sky are sweating, but the strong wind brings the Mid-Autumn Festival? Who is Feijing Wugen? Who will Hengqi marry? Asking about nothing at the bottom of the sea makes people feel worried in a trance. The whale is afraid of being thousands of miles long, and the vertical and horizontal touch breaks the frog of the Qionglou Jade Temple. Is it worth bathing in the water, asking the ups and downs of the clouds, cranes and rabbits? If Tao Qi was fine, why did he gradually become like a hook? (Xin Qiji's "Magnolia")

The full moon is obviously particularly good

●This month and next month, August, the mountains and mountains are beautiful, and the mountains of Wushan are very beautiful; BR /