Which star in the celestial body does the moon belong to?

Satellite satellite refers to a natural or artificial celestial body that runs in orbit around the planet.

The moon is the most obvious example of a natural satellite. In the solar system, all planets except Mercury and Venus have natural satellites. There are at least 160 known natural satellites in the solar system (including the larger debris that constitutes the planetary ring). Natural satellites are planets orbiting planets and planets orbiting stars. For example, in the solar system, the sun is a star, and planets such as our earth revolve around the sun, while planets such as the moon, Enceladus and Tianwei revolve around our earth. These planets are called natural satellites of planets. Jupiter has the largest number of natural satellites, of which 17 has been confirmed, and at least 6 remain to be confirmed. Natural satellites vary in size and are very different from each other. Some of them are only a few kilometers in diameter, such as two small satellites of Mars and some small satellites around Jupiter, Saturn and Uranus. Several of them are larger than Mercury, for example, Titan, Ganymede and Callisto, all of which are over 5,200 kilometers in diameter.

With the continuous development of modern science and technology, mankind has developed a variety of artificial satellites, which, like natural satellites, are also orbiting planets (mostly the earth). The concept of artificial satellite may have started with 1870. The first artificial satellite officially put into orbit was Sputnik 1 launched by the former Soviet Union in 1957. Since then, thousands of planes have flown around the earth. Satellites have also been launched into orbit around Venus, Mars and the moon. Satellites are used in scientific research and have become indispensable tools in modern communication, weather forecast, earth resource exploration and military reconnaissance.

Since 1957, when the Soviet Union put the world's first artificial satellite into orbit around the earth, humans have launched a large number of aircraft into the vast universe. The latest worldwide satellite database recently released by an American organization called "Union of Worried Scientists" shows that there are 795 satellites in Earth orbit, more than half of which belong to the United States, the only superpower in the world, and the number of satellites it owns has exceeded the sum of all other countries, reaching 4 13, and the number of military satellites has reached more than a quarter. 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 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.

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.

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. The moon's orbit around the earth is circular, with an average distance of 363,300 kilometers at perigee (when it is closest to the earth) and 405,500 kilometers at apogee (when it is farthest from the earth), with a difference of 42,200 kilometers.

The moon, like the earth, is a flat sphere with slightly flat north and south poles and slightly higher equator. Its average polar radius is 500 meters shorter than the equatorial radius, and the north and south poles are also asymmetrical. The North Pole rises and the South Pole sinks about 400 meters.

When the moon goes around the earth, it also goes around 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.

As a result of this strange rotation of the moon, the moon always faces the earth with the same half, and what the back of the moon looks like can never be seen from the earth. Only through the detector can we solve the mystery on the back of the moon. This wish of mankind was realized as early as 30 years ago. Today's large astronomical telescopes can distinguish targets about 50 meters (equivalent to 14-story buildings) on the moon.

The moon has many interesting reputations in China's ancient poems: jade exemption (whoever tries to climb the stairs to find jade exemption, who covers the silver que-Xin Qiji); Luminous (luminous, why do you have children when you die? —— Qu Yuan); Su E (Su E is another name for the moon-Youxue Qionglin); Ice wheel (the jade hook decides who to hang, but the ice wheel is helpless-land tour); Jade wheel (jade wheel meets wet light, Luan Pei meets a stranger in Gui Xiang-Li He); Jade toad (cold night fog outside, three or five jade toad autumn-Fang Gan); Gui' ao (Gui' ao flies to a sunny place and enjoys a cool day in autumn-Su Shi); Toad (Fujian set sail, but toad lost his reunion-Jia Dao); Ancient pictures (Yang birds don't come out of the valley, and ancient pictures are half hidden-Li Bai); Chan Juan (I wish you a long life, take Wan Li Road * * * Chan Juan-Su Shi). In addition, there are many unique nicknames on the moon, such as Jade Bow, Jade Gui, Jade Plate, Jade Hook, Jade Mirror, Ice Mirror, Guanghan Palace, Chang 'e and Jade Sheep.