A little knowledge about the moon

1. Popular science knowledge about the moon

The moon is also called the moon.

There is basically no water on the moon, so there is no weathering, oxidation and water corrosion on the earth, and there is no sound transmission. There is a silent world everywhere. The moon itself does not shine, the sky is always dark, and the sun and stars can appear at the same time.

There is almost no atmosphere on the moon, so there is a great temperature difference between day and night on the moon. During the day, where the sun shines vertically, the temperature is as high as127.25℃; The temperature at night can be as low as-183.75℃.

Because there is no atmospheric barrier, the intensity of sunlight on the surface of the moon is stronger than that on the earth 1/3 or so. The intensity of ultraviolet rays is also much stronger than the surface of the earth. Due to the lack of atmosphere on the moon, many strange phenomena will be seen on the moon, such as the dark sky on the moon, direct sunlight and brilliant sunshine; It's dark where you can't shine.

Therefore, we can see that the surface of the moon is bright and dark. As there is no air to scatter light, the stars on the moon no longer seem to twinkle.

The moon is full of rocks and craters. The whole surface of the moon is covered with gravel and residual soil.

The surface of the moon seen from the earth has bright areas and dark gray parts. The original bright part is the mountains and highlands on the surface of the moon, and the dark gray part is the plain on the surface of the moon.

The moon is smaller than the earth, with a diameter of 3476 kilometers, which is about 3/ 1 1. The surface area of the moon is about114 of the surface area of the earth, slightly smaller than that of Asia. Its volume is 1/ 49 of the earth, in other words, the earth has 49 satellites.

The mass of the moon is1/81of the earth; The average density of matter is 3.34 grams per cubic centimeter, which is only 3/5 of the density of the earth. The gravity on the moon is only 1/6 of that of the earth, that is to say, something weighing 6 kilograms will only weigh 1 kg on the moon.

When people walk on the moon, their bodies look relaxed and they can jump up with a little effort. Astronauts think that walking on the moon seems more enjoyable than walking on the earth.

2. Common sense about the moon

Mid-Autumn Festival is a traditional festival in China.

According to historical records, the word "Mid-Autumn Festival" first appeared in the book Zhou Li. In the Wei and Jin Dynasties, there was a record of "telling Shangshu Town about the cow's confusion, crossing the river in mid-autumn, and traveling incognito around".

It was not until the early years of the Tang Dynasty that the Mid-Autumn Festival became a fixed festival. The Book of Emperor Taizong recorded the Mid-Autumn Festival on August 15.

The prevalence of Mid-Autumn Festival began in the Song Dynasty, and it became one of the major festivals in China in the Ming and Qing Dynasties. This is also the second largest traditional festival in China after the Spring Festival.

According to the China calendar, the eighth month of the lunar calendar is in the middle of autumn, and the second month of autumn is called "Mid-Autumn Festival", and August 15th is in the middle of it, so it is called "Mid-Autumn Festival". Mid-Autumn Festival has many nicknames: it is called "August Festival" and "August and a half" because it falls on August 15th; Because the main activities of the Mid-Autumn Festival are all around the moon, it is also commonly known as the "Moon Festival" and "Moon Festival". The full moon in Mid-Autumn Festival symbolizes reunion, so it is also called "Reunion Festival".

In the Tang Dynasty, the Mid-Autumn Festival was also called "correcting the moon". The record of "Reunion Festival" was first seen in the Ming Dynasty.

"Journey to the West Lake" says: "August 15th is the Mid-Autumn Festival, and people send moon cakes to show their reunion". "A Brief Introduction to the Scenery of the Imperial Capital" also said: "On August 15th, the moon was sacrificed, the cakes were round, the melons were wrongly divided, and the petals were carved with lotus flowers.

..... Anyone who returns to Ning with a wife will return to her husband's family one day, which is called "Reunion Festival". On the night of Mid-Autumn Festival, there is a custom of "reunion" in most parts of our country, that is, flipping a small cake symbolizing reunion, which is similar to a moon cake. The cake contains sugar, sesame, sweet-scented osmanthus and vegetables, and the moon, sweet-scented osmanthus tree and rabbit are pressed outside.

After the Mid-Autumn Festival, the elders at home will divide the cake into pieces according to the number of people, and each person will have one. If someone is not at home, leave one for them to show family reunion. During the Mid-Autumn Festival, there are fewer clouds and more fog, and the moonlight is bright and bright. In addition to a series of activities such as enjoying the moon, offering sacrifices to the moon, eating moon cakes and wishing for reunion, there are activities such as dancing grass dragons and building stupas in some places.

In addition to moon cakes, all kinds of seasonal fresh fruits and dried fruits are also delicious in the Mid-Autumn Festival. Another explanation for the origin of Mid-Autumn Festival is that the 15th day of the eighth lunar month happens to be the time when rice is ripe, and all families worship the land god.

Mid-Autumn Festival may be the legacy of Qiubao. One year in ancient times, ten suns appeared in the sky, which made the earth smoke and the ocean dry up, and ordinary people could not live any longer. This incident alarmed a hero named Hou Yi. He climbed to the top of Kunlun Mountain, drew his bow and shot down nine redundant suns in one breath.

Hou Yi has made great achievements in the world and is respected and loved by the people. Many people with lofty ideals come here to study and be teachers. The treacherous and cunning Meng Peng also mixed in.

Soon, Hou Yi married a beautiful and kind wife named Chang 'e. Besides hunting, Hou Yi spends all his time with his wife, and people envy this beautiful and loving couple.

One day, Hou Yi went to Kunlun Mountain to visit friends and seek truth. He happened to meet the Queen Mother passing by and asked her for a bag of elixir. It is said that taking this medicine can instantly ascend to heaven and become immortal.

However, Hou Yi was reluctant to leave his wife, so he had to temporarily give the elixir to Chang 'e. Chang 'e hid the medicine in the dresser's treasure chest, but Meng Peng saw it.

Three days later, Hou Yi led his entourage out hunting, while Meng Peng with ulterior motives pretended to be ill. Shortly after Hou Yi led the crowd to leave, Meng Peng broke into the backyard of the back room with a sword in his hand, threatening Chang 'e to hand over the elixir.

Chang 'e knew that she was no match for Meng Peng. In times of crisis, she made a decisive decision, turned around and opened the treasure chest, took out the elixir and swallowed it in one gulp. Chang 'e swallowed the medicine and immediately floated off the ground, rushed out of the window and flew into the sky.

Because Chang 'e was worried about her husband, she flew to the nearest moon and became a fairy. In the evening, when Hou Yi came home, the maids cried and told what happened during the day.

Hou Yi was surprised and angry, and drew his sword to kill the villain. Meng Peng has escaped. I was so angry that Hou Yi beat his chest and shouted.

The grief-stricken Hou Yi looked up at the night sky and called the name of his beloved wife. At this time, he was surprised to find that today's moon is particularly bright and bright, with a swaying figure resembling Chang 'e.

Hou Yi hurriedly sent someone to Chang 'e's favorite back garden, set up a table sweetmeats, put on her favorite honey-eating fresh fruit, and offered a memorial service to Chang 'e at the Moon Palace. After hearing the news that the Goddess Chang'e flying to the moon became an immortal, people made an incense table under the moon and prayed for good luck and peace to the kind Chang 'e.

Since then, the custom of Mid-Autumn Festival in Yue Bai has spread among the people. Artemis, the goddess of the moon in ancient Greek mythology.

She is the sister of Apollo, the sun god. She is beautiful and a very good archer. She is in charge of hunting, often accompanied by her beloved bow and hound. She drives a silver carriage through the night sky every day, representing the cold, loneliness and dead road at night.

She is also the patron saint of unmarried girls-she herself is unmarried for life, and there is a sad story in it. Poseidon, the sea king, had a son named Orion. He likes archery very much. He is a good hunter and likes to run wildly on the sea.

The moon goddess likes Oreos very much. They know each other and love each other. They often hunt in the jungle together and run wildly at sea. Apollo, the goddess' brother, hated Oreon and disliked the relationship between his sister and Oreon, so he decided to get rid of Oreon.

One day, when Oreon was flying on the sea, Apollo covered Oreon with golden light to hide him, so that no one could see Oreon's true face. Then he encouraged his sister, Moon Goddess, who likes archery, to take gold objects in the distance as targets. Of course, the moon goddess didn't know it was her brother's plot, so she shot an arrow and hit Oregon in the head.

Later, when she learned that she had shot her sweetheart Olian, she fell into despair and cried day and night. In order to cherish her love for Oregon forever, she asked Zeus to lift Oregon to the sky, hoping that she could see it at any time when she was running in the sky in a silver carriage.

Zeus accepted her request and turned Orion into a constellation in the sky. The goddess swore that she would never get married, and that she would stay with Oregon in the night sky forever.

Themis, the goddess of the moon, likes oak trees very much and always takes her oak stick with her when hunting. People think she is the goddess of oak.

In ancient Greece, when people offered sacrifices to the goddess of the moon, they lit oak torches, which later turned into offering cookies and lighting candles, and finally evolved into.

3. Little knowledge about the moon (20 words)

The moon rotates counterclockwise from west to east, and also rotates counterclockwise around the earth.

Because of tidal locking, the moon's rotation period is equal to its period of revolution around the earth, which is about 28 Earth days. In the end, the moon always faces the earth "frontally" and its back always faces the earth.

There is no wind, no rain, no clouds in the sky and no weather change on the surface of the moon. No matter day or night, the sky on the moon is always dark

Looking up at the stars on the moon will be brighter than on the earth; Looking at the stars on the back of the moon will be brighter than looking at the front of the moon. Extended data:

The split theory of the birth of the moon: As early as 1898, George Darwin, the son of the famous biologist Darwin, pointed out in the article Tides and Similar Effects in the Solar System that the moon was originally a part of the earth, but later, due to the rapid rotation of the earth, some substances on the earth were thrown out, which formed the moon after leaving the earth, and the pit left on the earth was the Pacific Ocean.

This view was quickly opposed by some people. They think that it is impossible to throw such a big thing at the speed of the earth's rotation.

Besides, if the moon was thrown out by the earth, then the material composition of the two should be the same. However, through the analysis of the rock samples brought back from the moon by Apollo 12 spacecraft, it is found that there is a great difference between them.

The rocks on the surface of the moon are extremely old, ranging from 3 billion years to 4.2 billion years. The oldest rocks on the earth's surface are limited to metamorphic rocks exposed in some areas 3.8 billion years ago, while the rocks on the bottom of the Pacific Ocean are extremely young, which is completely contrary to the "split" theory. People's Network-The Little-known "Other Side" of the Moon.

4. Little knowledge about the moon (20 words)

The moon rotates counterclockwise from west to east, and also rotates counterclockwise around the earth. Because of tidal locking, the moon's rotation period is equal to its period of revolution around the earth, which is about 28 Earth days. In the end, the moon always faces the earth "frontally" and its back always faces the earth.

There is no wind, no rain, no clouds in the sky and no weather change on the surface of the moon. No matter day or night, the sky on the moon is always dark Looking up at the stars on the moon will be brighter than on the earth; Looking at the stars on the back of the moon will be brighter than looking at the front of the moon.

Extended data:

The split theory of the birth of the moon;

As early as 1898, George Darwin, the son of the famous biologist Darwin, pointed out in the article Tides and Similar Effects in the Solar System that the moon was originally a part of the earth, but later, due to the rapid rotation of the earth, some substances on the earth were thrown out, which formed the appearance of the moon after it left the earth, and the pit left on the earth was the Pacific Ocean.

This view was quickly opposed by some people. They think that it is impossible to throw such a big thing at the speed of the earth's rotation. Besides, if the moon was thrown out by the earth, then the material composition of the two should be the same. However, through the analysis of the rock samples brought back from the moon by Apollo 12 spacecraft, it is found that there is a great difference between them.

The rocks on the surface of the moon are extremely old, ranging from 3 billion years to 4.2 billion years. The oldest rocks on the earth's surface are limited to metamorphic rocks exposed in some areas 3.8 billion years ago, while the rocks on the bottom of the Pacific Ocean are extremely young, which is completely contrary to the "split" theory.

People's Network-The Little-known "Other Side" of the Moon

5. Common sense about the moon

Mid-Autumn Festival is a traditional festival in China.

According to historical records, the word "Mid-Autumn Festival" first appeared in the book Zhou Li. In the Wei and Jin Dynasties, there was a record of "telling Shangshu Town about the cow's confusion, crossing the river in mid-autumn, and traveling incognito around".

It was not until the early years of the Tang Dynasty that the Mid-Autumn Festival became a fixed festival. The Book of Emperor Taizong recorded the Mid-Autumn Festival on August 15.

The prevalence of Mid-Autumn Festival began in the Song Dynasty, and it became one of the major festivals in China in the Ming and Qing Dynasties. This is also the second largest traditional festival in China after the Spring Festival.

According to the China calendar, the eighth month of the lunar calendar is in the middle of autumn, and the second month of autumn is called "Mid-Autumn Festival", and August 15th is in the middle of it, so it is called "Mid-Autumn Festival". Mid-Autumn Festival has many nicknames: it is called "August Festival" and "August and a half" because it falls on August 15th; Because the main activities of the Mid-Autumn Festival are all around the moon, it is also commonly known as the "Moon Festival" and "Moon Festival". The full moon in Mid-Autumn Festival symbolizes reunion, so it is also called "Reunion Festival".

In the Tang Dynasty, the Mid-Autumn Festival was also called "correcting the moon". The record of "Reunion Festival" was first seen in the Ming Dynasty.

"Journey to the West Lake" says: "August 15th is the Mid-Autumn Festival, and people send moon cakes to show their reunion". "A Brief Introduction to the Scenery of the Imperial Capital" also said: "On August 15th, the moon was sacrificed, the cakes were round, the melons were wrongly divided, and the petals were carved with lotus flowers.

..... Anyone who returns to Ning with a wife will return to her husband's family one day, which is called "Reunion Festival". On the night of Mid-Autumn Festival, there is a custom of "reunion" in most parts of our country, that is, flipping a small cake symbolizing reunion, which is similar to a moon cake. The cake contains sugar, sesame, sweet-scented osmanthus and vegetables, and the moon, sweet-scented osmanthus tree and rabbit are pressed outside.

After the Mid-Autumn Festival, the elders at home will divide the cake into pieces according to the number of people, and each person will have one. If someone is not at home, leave one for them to show family reunion. During the Mid-Autumn Festival, there are fewer clouds and more fog, and the moonlight is bright and bright. In addition to a series of activities such as enjoying the moon, offering sacrifices to the moon, eating moon cakes and wishing for reunion, there are activities such as dancing grass dragons and building stupas in some places.

In addition to moon cakes, all kinds of seasonal fresh fruits and dried fruits are also delicious in the Mid-Autumn Festival. Another explanation for the origin of Mid-Autumn Festival is that the 15th day of the eighth lunar month happens to be the time when rice is ripe, and all families worship the land god.

Mid-Autumn Festival may be the legacy of Qiubao. One year in ancient times, ten suns appeared in the sky, which made the earth smoke and the ocean dry up, and ordinary people could not live any longer. This incident alarmed a hero named Hou Yi. He climbed to the top of Kunlun Mountain, drew his bow and shot down nine redundant suns in one breath.

Hou Yi has made great achievements in the world and is respected and loved by the people. Many people with lofty ideals come here to study and be teachers. The treacherous and cunning Meng Peng also mixed in.

Soon, Hou Yi married a beautiful and kind wife named Chang 'e. Besides hunting, Hou Yi spends all his time with his wife, and people envy this beautiful and loving couple.

One day, Hou Yi went to Kunlun Mountain to visit friends and seek truth. He happened to meet the Queen Mother passing by and asked her for a bag of elixir. It is said that taking this medicine can instantly ascend to heaven and become immortal.

However, Hou Yi was reluctant to leave his wife, so he had to temporarily give the elixir to Chang 'e. Chang 'e hid the medicine in the dresser's treasure chest, but Meng Peng saw it.

Three days later, Hou Yi led his entourage out hunting, while Meng Peng with ulterior motives pretended to be ill. Shortly after Hou Yi led the crowd to leave, Meng Peng broke into the backyard of the back room with a sword in his hand, threatening Chang 'e to hand over the elixir.

Chang 'e knew that she was no match for Meng Peng. In times of crisis, she made a decisive decision, turned around and opened the treasure chest, took out the elixir and swallowed it in one gulp. Chang 'e swallowed the medicine and immediately floated off the ground, rushed out of the window and flew into the sky.

Because Chang 'e was worried about her husband, she flew to the nearest moon and became a fairy. In the evening, when Hou Yi came home, the maids cried and told what happened during the day.

Hou Yi was surprised and angry, and drew his sword to kill the villain. Meng Peng has escaped. I was so angry that Hou Yi beat his chest and shouted.

The grief-stricken Hou Yi looked up at the night sky and called the name of his beloved wife. At this time, he was surprised to find that today's moon is particularly bright and bright, with a swaying figure resembling Chang 'e.

Hou Yi hurriedly sent someone to Chang 'e's favorite back garden, set up a table sweetmeats, put on her favorite honey-eating fresh fruit, and offered a memorial service to Chang 'e at the Moon Palace. After hearing the news that the Goddess Chang'e flying to the moon became an immortal, people made an incense table under the moon and prayed for good luck and peace to the kind Chang 'e.

Since then, the custom of Mid-Autumn Festival in Yue Bai has spread among the people. Artemis, the goddess of the moon in ancient Greek mythology.

She is the sister of Apollo, the sun god. She is beautiful and a very good archer. She is in charge of hunting, often accompanied by her beloved bow and hound. She drives a silver carriage through the night sky every day, representing the cold, loneliness and dead road at night.

She is also the patron saint of unmarried girls-she herself is unmarried for life, and there is a sad story in it. Poseidon, the sea king, had a son named Orion. He likes archery very much. He is a good hunter and likes to run wildly on the sea.

The moon goddess likes Oreos very much. They know each other and love each other. They often hunt in the jungle together and run wildly at sea. Apollo, the goddess' brother, hated Oreon and disliked the relationship between his sister and Oreon, so he decided to get rid of Oreon.

One day, when Oreon was flying on the sea, Apollo covered Oreon with golden light to hide him, so that no one could see Oreon's true face. Then he encouraged his sister, Moon Goddess, who likes archery, to take gold objects in the distance as targets. Of course, the moon goddess didn't know it was her brother's plot, so she shot an arrow and hit Oregon in the head.

Later, when she learned that she had shot her sweetheart Olian, she fell into despair and cried day and night. In order to cherish her love for Oregon forever, she asked Zeus to lift Oregon to the sky, hoping that she could see it at any time when she was running in the sky in a silver carriage.

Zeus accepted her request and turned Orion into a constellation in the sky. The goddess swore that she would never get married, and that she would stay with Oregon in the night sky forever.

Themis, the goddess of the moon, likes oak trees very much and always takes her oak stick with her when hunting. People think she is the goddess of oak.

In ancient Greece, when people offered sacrifices to the goddess of the moon, they lit oak torches, which later turned into offering cookies and lighting candles, and finally evolved into.

6. Cultural knowledge about the moon

The traditional food of Zhu Yuanzhang Uprising Mid-Autumn Festival is moon cakes, which are round, symbolizing reunion and reflecting people's good wishes for family reunion.

Eating moon cakes in the Mid-Autumn Festival is said to have started in the Yuan Dynasty. At that time, Zhu Yuanzhang led the Han people to resist the tyranny of the Yuan Dynasty, agreed on the August 15th uprising, and put a note in the moon cake to convey the news. The custom of eating moon cakes on Mid-Autumn Festival spread among the people.

Later, Zhu Yuanzhang finally overthrew the Yuan Dynasty and became the first emperor of the Ming Dynasty. Although Manchu people later entered China, people still celebrated this festival, which symbolized the overthrow of alien rule. V WU GANG cuts laurel v Legend has it that there is a laurel tree 500 feet high on the moon.

There was a man named WU GANG in the Han Dynasty who was obsessed with fairy tales and didn't concentrate on reading. He was banished to the moon to cut laurel, but the laurel in the moon was also cut, and it was cut endlessly, so later generations could see the image of WU GANG cutting laurel endlessly in the middle of the month. Among many beautiful legends, one is that the emperor of the Tang Dynasty visited the Moon Palace.

Ming Chengzu loved the moon, and his enthusiasm made him eager to visit the Moon Palace. His entourage, the wise man Tian (the version of China is mostly Taoist Luo, and some people say that it is Zhang or the mage Ye Fashan) accompanied Ming Chengzu to start a trip to the Moon Palace. He said to Ming Chengzu, "Your Majesty, this crutch will lead us to the moon. Please don't open your eyes. I'll throw my crutches into the sky.

When I arrived at the Moon Palace, I saw the ivory steps, which were bright. They met Chang 'e, the master of the Moon Palace. Her husband Hou Yi is the guardian of the Heavenly Palace. He is famous for shooting down nine suns in the sky, and he got the elixir of life. But it was his wife Chang 'e who took the elixir of life, so she lived forever and flew to the moon. Chang 'e, who has always been beautiful, pointed to the hill next door, where Yutu was working on medicine. This is a panacea for all diseases. As for the osmanthus vine, it stands on the ground covered with cyanine moss in the moon palace. It is said that it has begun to grow branches, leaves and flowers ... 1, the line at the foot of my bed is so bright, can it have frost? .

Li Bai 2, looking up, I found that it was moonlight. When I sank back again, I suddenly thought of home. Li Bai 3, the moon is like a mirror, and the sea clouds are like a palace.

Li Bai 4, until, holding up my cup, I asked the moon to bring me my shadow and make the three of us. Li Bai 5, a bright moon hangs high in the capital, and it is tempered.

Li Bai 6, the bright moon rises from the mountains in the sky, in the infinite haze of the sea of clouds. Li Bai 7, drunk on the moon, the sage of dreams, the temptation of flowers, the monarch is the emperor.

Li Bai 8, behind her closed window, why is she still waiting, looking at the glory of the autumn moon through the crystal glass? . Li Bai 9. My heart is full of sorrow, and the moon is full of sorrow. I will always follow you until Yelangxi.

Li Bai 10, we both hold high the idea of going far away and yearn for the sky and the bright moon. Li Bai 1 1, Emei Mountain is half moon and autumn, and it is reflected in Pingqiang River.

Li Bai 12 The breeze blows my belt, and the moon shines on my piano. Wang Wei 13, the voice is too low for anyone to hear except my comrade-in-arms Mingyue.

The moonlight shines in the pine forest and the crystal stone shines in the stream. Wang Wei 15, the puddle widens with the moon, and the torrent bends with the mountain.

Ma Dai 16, wild geese are soaring in the bright moonlight, and the chief of Tatar people is fleeing in the dark. Lu Lun 17, he knows that the dew will be frost tonight, and how bright the moonlight at home is! .

Du Fu 18, the windows in the sky are shining, and the moonlight on the nine cloud platforms is shining. Du Fu, 19, Chen Xing treated the garbage and brought the Moon Lotus hoe home.

Tao Yuanming 20, speechless alone in the west wing, the moon is like a hook. Li Yu 2 1, the bright moon surprises the magpie, and the breeze sings at midnight.

Xin Qiji 22, poor September third night, dew like a pearl like a bow. Bai Juyi 23, a bullet in water and a bullet in a month, half into the river, half into the clouds.

Couplet 24, the moonlight is deeper than half a house, and the big dipper is withered south. When Liu looked in the mirror at the age of 25, she saw that her hair cloud was changing, but she used her evening song to challenge the cold of the moonlight.

Li Shangyin 26 will bow like a full moon and look at Sirius in the northwest. Su Shi 27, the court is as empty as water, the algae in the water is horizontal, and the shadows of bamboo and cypress are also covered.

Su Shi.

7. Common sense about the moon

At present, there is no conclusion about the origin of the moon: there are roughly three schools of thought about the origin of the moon, but there is no conclusion.

Some scientists believe that the moon, like the earth, was formed by the gas and dust of the universe 4.6 billion years ago; Some people think that the moon is a child of the earth, and it is split from the earth. But the data brought back by Apollo several times show that the composition of the moon and the earth is very different.

Many scientists believe that the moon was accidentally sucked into the gravity field many years ago, so it was accidentally brought into Earth orbit. But some people cite celestial mechanics to oppose this statement.

The moon is older than the earth: to scientists' surprise, 99% of the rocks brought back from the moon are older than 90% of the ancient rocks on the earth. The moon rocks brought back by astronauts have been measured for 4.3 billion to 4.6 billion years, which is equivalent to the history of the solar system.

Soil is older than rocks: in the "quiet sea" where American astronauts landed for the first time, soil is older than rocks. According to analysis, the difference between them is 654.38+0 billion years.

Chemical analysis shows that the soil on the moon did not evolve from rocks and may have come from other places. The impact will make a loud noise: Apollo will hit the surface of the moon during the lunar exploration, and the spacecraft and rockets will also hit when they return.

But every time, the moon will ring like a gong or a big clock. When Apollo 12 explored the moon, the echo of the moon lasted for four hours. At present, no scientist can explain this phenomenon. There are rare metals in the shadow area: if you look at the moon on the earth, you will see some shadows. When astronauts landed in the shadow area of this plain, they found it difficult to drill holes in its surface. After research, the soil samples here contain metal elements such as titanium, thulium and yttrium. And scientists are very surprised, because these metal elements can only be melted at a very high temperature-above 6000 degrees Celsius and mixed with some surrounding rocks.

Pure iron particles will not rust: all rock samples brought back by astronauts from the moon contain pure iron particles, which scientists believe are not from meteorites. According to experts, these pure iron particles have not rusted for many years after being brought back to the earth. It is the first time that pure iron does not rust in the scientific community.

The surface is as smooth as a mirror: the surface of the moon is as smooth as a mirror in many places. It seems that I have been "burned" by some unknown heat.

According to expert analysis, this is not caused by a huge meteorite impact, but some scientists believe that the high heat from the sun is the main factor. Magnetism is shocking: in early lunar research, it was said that there was no magnetic field on the moon. In recent years, after analyzing the moon rock, people know that it has strong magnetism.

But if the moon's rock really has a magnetic field, it should have an iron core, but the current data tell us that it is impossible for the moon to have such a huge hot core, and it is impossible to obtain magnetism from the magnetic field on the earth, because the moon must be very close to the earth if it wants to obtain magnetism from the earth. If so, it will be destroyed by gravity. Concentrate at the bottom of the shell: the data brought back by space exploration show that there is a large piece of concentrate under the shell of the moon, and it has gravity, so the spacecraft can't help tilting when flying over.

Scientists only know that these concentrates are a heavy and dense substance, and the rest know nothing. The orbit radius of the moon is 384,400 kilometers away from the Earth, and the diameter of the satellite is 3,476 kilometers. The satellite mass is 7.35e22. The moon, the nearest star, is neither a star nor a planet, but the only natural satellite orbiting the earth.

Of course, the moon was known as early as prehistoric times. It is second only to the sun in the sky.

Because the moon orbits the earth once a month, the angles between the earth, the moon and the sun are constantly changing; We call it the new moon. It takes 29.5 days (709 hours) for a continuous new moon to appear, which varies with the orbital period of the moon (measured by stars) and the synchronous revolution of the earth around the sun.

The moon has no atmosphere. However, the evidence from Clementine aircraft shows that there may be solid water ice at the south pole of the moon, which is the permanently dark side of the Great Circle Mountain.

This has been confirmed by the lunar probe. Obviously, there is ice in the north pole of the moon.

There are two main landforms on its surface: huge craters and ancient plateaus, and a relatively smooth young moon sea. The topography of the Moon Sea (covering 65,438+06% of the moon's surface) was eroded by the fiery lava from the volcano.

Most of the surface is covered by dust in calcareous soil and stone fragments hit by meteors. I don't know why, the moon and the sea are concentrated on the side close to the earth.

Most craters and volcanoes near the earth are named after famous scientists in history, while most of the ones on the back are named after modern times. 1959 the Soviet aircraft Luna-2 visited the moon for the first time, which is also the first time that humans have explored non-earth stars.

It is also the only planet whose surface samples have been brought back. In the summer of 1994, Clementine aircraft drew a lot of maps of the moon.

The lunar prospector is now orbiting the moon. The gravitational field between the earth and the moon has formed an interesting phenomenon.

The most obvious phenomenon is the tidal phenomenon. The point where the earth is facing the moon has the greatest attraction, and the opposite point is relatively weak.

The earth, especially the ocean, is not completely fixed, but extends slightly to the moon. From the surface of the earth, we will see that there are two expansion points on the surface of the earth, one facing the moon and the other facing the opposite side.