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.
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℃; The temperature at night can be as low as-183℃. 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 exposed rocks and the outline of 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. In the process of orbiting the earth, the moon should orbit the sun with the earth. That is to say, after the moon orbits the earth once, the space position it returns to is not the original starting point. It can be seen that the moon should participate in the movement of various systems in the process of movement. Like other celestial bodies, the moon is always in motion. The moon moves from west to east by more than 13 degrees on average every day, so the moon rises about 50 minutes later than the previous day. The rise and fall of the moon is a reflection of the earth's rotation; The movement from west to east is the result of the moon's revolution around the earth. One revolution of the moon around the earth is called "sidereal moon", with an average of 27 days, 7 hours and 43 minutes 1 1 sec. When the moon revolves around the earth, it also rotates. The moon's rotation period is equal to period of revolution, that is, 1: 1, and the time for the moon to go around the earth is the rotation period.
On the night of Mid-Autumn Festival, the moonlight is bright. The ancients regarded the full moon as a symbol of reunion, so August 15 was also called "Reunion Festival". Throughout the ages, vagrants who have lived in other places have pinned their affection on the moon. "Looking up, it turned out to be moonlight, and then sinking, I suddenly remembered my hometown." The spring breeze is green in Jiang Nanan, when the moon shines on me by the poet Li Bai in the Tang Dynasty, and the poem "People have joys and sorrows, and the moon is sunny" by Wang Anshi in the Song Dynasty. , are eternal songs.
From a scientific point of view, the moon is the only natural satellite of the earth and the closest celestial body to the earth. Its average distance from the earth is about 384,406,5438+0 km. Its average diameter is about 3476km, slightly larger than the earth's diameter 1/4. The surface area of the moon is 38 million square kilometers, which is not as large as that of our Asia. The mass of the moon is about 735 billion tons.
The moon we usually see is like a bright lamp. The moon itself does not shine, but reflects sunlight. Its brightness varies with the angular distance between the sun and the moon and the distance between the earth and the moon.
The surface of the ball is a desert composed of plains, peaks and valleys. There are also many craters formed by high-speed impact of space objects on the surface of the moon. There are also various special names such as ocean, sea, bay and lake. The crater is a bowl-shaped pit structure. There are more than 33,000 craters with a diameter greater than 1km. Many craters have a central peak or peak group in the center. The dark black spots seen by the naked eye on the moon are called the Moon Sea, which is a vast plain. There are 22 months of the sea. The largest is the storm ocean, covering an area of 5 million square kilometers. Because there is no atmosphere on the moon, the heat capacity and thermal conductivity of the materials on the surface of the moon are very low, so the temperature difference between day and night on the surface of the moon is very large.
The moon revolves around the earth in an elliptical orbit. The great circle cut by this orbital plane on the celestial sphere is called the "white road". The plane of the ecliptic does not coincide with the equator of the celestial sphere, nor is it parallel to the plane of the ecliptic, and its spatial position is constantly changing. The period is 173 days. The average inclination of the moon's orbit relative to the earth's orbit (ecliptic) is 5 09'.
The moon revolves around the earth and rotates at the same time, with a period of 27.438+066 days, which happens to be a sidereal moon, so we can't see the back of the moon. The libration is a wonderful phenomenon, which enables us to see 59% of the surface of the moon. The main reasons are as follows: 1. In different parts of the elliptical orbit, the rotation speed does not match the revolution angular speed. 2. The intersection of the white road and the equator. The cycle of the moon's rotation around the earth: 29.059 days in the first lunar month; Stellar moon 27.3 166.
Do you know that?/You know what? Do you know that?/You know what? During the operation of the moon, an eclipse will occur when it enters the shadow of the earth. How did the solar eclipse form? When the moon enters the penumbra of the earth, it is a penumbral eclipse; The moon enters the shadow of the earth and a partial lunar eclipse occurs; The moon all enters the umbra of the earth, which is the total lunar eclipse. Speaking of total lunar eclipse, I will tell you an interesting legend:1At the beginning of the 6th century, Columbus sailed to Jamaica in South America and had a conflict with the local aborigines. Columbus and his sailors were trapped in a corner, without food and water. The situation is very critical. Knowing that there would be a total lunar eclipse that night, Columbus shouted to the natives, "No food, no moonlight!" " "In the evening, Columbus's words came true, and there was no moonlight. When the natives saw this scene, they were afraid, so they quickly made peace with Columbus.
Eclipses always occur in sight (full moon), but not every time. Under normal circumstances, the moon either passes above the Earth's umbra or leaves under the Earth's umbra, and rarely or partially passes through the Earth's umbra, so an eclipse will not occur under normal circumstances.
There is more knowledge about the moon. Let's study hard and solve the "unknown" problem!