What's in mercury?

Question 1: What's in mercury? Among the planets in the solar system, Mercury is closest to the sun. During the day, the surface temperature of Mercury can reach 700K(427℃) above the absolute temperature scale. Because the rotation direction of Mercury is the same as the revolution direction, there is really a feeling of "passing days like years" on Mercury, with a day and night as long as 176 days. Because of this slow rotation relative to the sun, the sun is almost motionless in the sky, so the surface of Mercury is baked by sunlight for a long time. Therefore, among the planets in the solar system, the possibility of ice on Mercury should be the least. Nevertheless, the radar imaging system on the earth shows that the reflectivity of radar waves is very high near the north and south poles of Mercury. This phenomenon may indicate the existence of water ice in these places. The radar image also shows that there are ten craters nailed to these places, which may be traces left by the impact of comets. These places may never be exposed to sunlight, and the temperature is low enough, which provides the possibility for the long-term existence of water ice. At the same time, the exploration and discussion on whether there is water on the moon has aroused scientists' interest in whether there is water on Mercury. How to observe the evidence of water ice on mercury? Observing Mercury on Earth mainly depends on Arecibo large radio telescope, tawny glass antenna and giant radio telescope array located in Puerto Rico. The tawny glass wireless/radio telescope giant array uses a tawny glass parabolic satellite antenna 70 meters away from NASA's space tracking network, and the transmission frequency is 8.5 1GHz. A vertically circularly polarized radar wave signal with power of 460kW was detected. The reflected radar waves are received by the antennas of 26 radio telescope arrays of the National Radio Observatory. After calibrating and processing the reflected signal, it is found that the reflectivity of the Arctic region of Mercury is relatively high and the radar image is relatively bright. Arecibo radio telescope can emit S-band (frequency is 2.4GHz) vertically circularly polarized radar waves with a power of 240kw. After receiving, processing and filtering the radar echo reflected back to the ground, the radar reflectivity map of the surface of Mercury can be drawn, and the accuracy of this map can reach 15km. In the polar region of Mercury, there are about 20 irregular radar wave reflection areas, and the radar waves reflected by these areas also have obvious depolarization characteristics. Why is there water ice in the bright area of radar image? Water ice has a high reflectivity for radar waves, and the reflected radar waves have obvious depolarization characteristics, while silicate rocks on the surface of Mercury do not. Although the reflectivity of radar waves is not as good as that of some other icy satellites in the solar system, such as Europa, Ganymede and Callisto, compared with ordinary rocks, the polar regions of Mercury are still worthy of scientists' attention: arecibo radio telescope's detection results show that the highly reflective regions of radar waves in the polar regions of Mercury are mainly concentrated in polar craters. In the Antarctic region of Mercury, the location of the area with the highest reflection similar to the largest crater named Meng Chao-Fu is surprisingly close, while other small areas correspond to some small craters that have been demarcated. However, in most parts of Mercury's North Pole, the area containing some radar highlights is not imaged, so it cannot correspond to some known craters in the North Pole. However, generally speaking, the bright areas in radar echo images are related to the known craters in the polar regions of Mercury. Craters near the poles of Mercury can provide a permanent or almost permanent cold environment for the preservation of ice. The radar echo results show that the bright areas of those radar images may be related to some pure and unpolluted water ice. However, compared with the high reflectivity of pure water ice, those areas in the pit that show low reflectivity to radar waves may mean that the ice is covered with dust or soil or other substances. Although there is no direct evidence that there is ice in the polar regions of Mercury, the almost permanent shadow areas caused by craters corresponding to large areas of bright areas in radar images can be regarded as strong evidence that there is water ice on Mercury. But the cumulative reflection of radar waves can also be understood as the result of other substances, such as some metal sulfides, metal condensate, sodium salt deposits and so on. Of course, this has nothing to do with the existence of ice.

Question 2: What is Mercury like? Overview of mercury

Astronomical symbols:

Mercury is the smallest of the eight planets, larger than the moon 1/3, and the closest planet to the sun. Mercury's visual magnitude is between 0.4 and 5.5; Mercury is so close to the sun that it is often submerged by fierce sunlight, so telescopes can rarely observe it carefully. Mercury has no natural satellites. Satellites already close to Mercury include the American probe Mariner 10 and the American probe Messenger. Mariner 10 only photographed about 45% of the surface when it detected Mercury in 1974- 1975. Messenger passed by Mercury in June 65438+2008 10. Mercury is the fastest moving planet in the solar system.

The English name of Mercury comes from the Roman god Mercury. He is an emissary in Roman mythology. Mercury is the fastest planet in the solar system because it orbits the sun for about 88 days. The symbol is a short vertical line with a circle above and a semicircle (Unicode) below. This is the shape of Mercury's wand. In the 5th century, Mercury was actually considered as two different planets, because it often appeared alternately on both sides of the sun. When it appears in the evening, it is called mercury; But when it appeared in the morning, it was called Apollo to commemorate Apollo, the sun god. Pythagoras later pointed out that they were actually the same planet.

In ancient China, Mercury was called "the morning star" or "the evening star".

The Book of Jin: The Second Astronomical Annals (Taking Biography of Qi Yao's Miscellaneous Stars as an Example)

"The stars say that the northern winter water, wisdom, also listen to. Loss of wisdom and hearing, violation of winter season, injury to water vapor, punishment to see the stars. When the stars meet, the main punishment is the main punishment, the main Tingwei, the main, and Yan, Zhao and Dai Bei; The image of the prime minister. It is also the spirit of war and the symbol of fighting. It is also said that the army is in the wild, the stars prefer the generals, and no army is a crime. And yin and yang, should be effective, not at that time. When the time comes, the cold department will be dishonored and the state will be hungry. When you can't get out, it means that the soldiers are big. It is located in the center of the room, and the ground will move. It is also said that the stars go in and out wildly and often dominate Yi Di. And the barbarian star is also the master of the gains and losses of criminal law. Yellow is small, but it moves big. Light catches the moon, and the country is flooded. 」

Hermes In ancient Roman mythology, Mercury was the god of commerce, travel and theft, that is, Hermes in ancient Greek mythology, the god who sent information to the gods. Perhaps it is because Mercury moves very fast in the air that it got the name.

Mercury was discovered as early as 3000 BC in Sumerian times, and the ancient Greeks gave it two names: Apollo when it first appeared in the morning and Hermes shining in the night sky. However, ancient Greek astronomers knew that these two names actually refer to the same star, and Heraclitus (a Greek philosopher in the 5th century BC) even thought that Mercury and Venus revolved around the sun instead of the earth.

Mercury's orbit deviates from the perfect circle to a great extent. The closest point is only 46 million kilometers away from the sun, but the apohelion is 70 million kilometers away. At the perihelion of the orbit, according to precession (precession: precession of the earth's axis causes vernal equinox to slowly move westward at a speed of 0.2 per year, making the tropical year shorter than the sidereal year), it moves around the sun at a very slow speed. There are two kinds of precession: solar precession and planetary precession. The latter is the change of ecliptic plane caused by planetary gravity. ) In the19th century, astronomers observed the orbital radius of Mercury very carefully, but they could not explain it properly with Newtonian mechanics. The subtle difference between the actual observed value and the predicted value is a small problem (one seventh of a degree per thousand years), but it has been puzzling astronomers for decades. Some people think that there is another planet in the orbit near Mercury (sometimes called Vulcan, or "wishing star"), which explains this difference. As a result, the final answer is quite dramatic: Einstein's general theory of relativity. In the early days when people accepted this theory, the correct prediction of mercury's motion was a very important factor. Mercury revolves around the sun because its gravitational field is extremely huge. According to the general theory of relativity, mass produces a gravitational field, which can be regarded as mass, so the giant gravitational field can be regarded as mass, which produces a small force field and makes its orbit deviate. Similar to the divergence of electromagnetic waves, the changing magnetic field generates an electric field, and the changing electric field generates a magnetic field, which is transmitted to a distance. -translation notes)

Before 1962, people always thought that the time of Mercury's rotation was the same as that of its revolution, so the side facing the sun was unchanged. This is very similar to the fact that the moon always faces the earth with the same half face. ........................................................................................................................................................... & gt

Question 3: Is Mercury full of water? Give you two versions. Um ...

1 If Mars is full of fire, then of course Mercury can't be full of water, because the one full of fire is called Sun = =

Mercury is the smallest planet in the solar system, about the size of the moon. 1974, human beings launched a probe to Mercury for the first time, and found that there were craters, mountains, plains, basins and canyons on Mercury, just like the moon.

Mercury is the closest planet to the sun, with its back to the sun, and its temperature is very high, reaching more than 400℃. At such a high temperature, metals such as tin and lead will melt and water will turn into steam. If mercury really had water, the side facing away from the sun would have turned into steam and dispersed into the universe under the scorching sun. In addition, mercury is small and attractive, and its gravity has no ability to attract water vapor to its side. Mercury's side facing away from the sun has not seen sunlight for a long time, and the temperature is below-173℃, so there can be no liquid water.

There is no water on mercury. Why is it called mercury In ancient China, the sun, the moon and the planets were represented by the five elements of yin and yang, and the silly planets were called gold, wood, water, fire and earth. Mercury is just a name given to it, not because it has a lot of water on it, just as Venus is not all gold.

Question 4: What does Mercury mean in the constellation? The rising constellation is your protective color and the feeling you give others, which will strongly affect you after you are 30 years old. The moon constellation is in charge of your inner world and loves to think. It is what you say and do after thinking, which strongly affects your life after 20 years old. Mars rules your mobility, sexual ability and sexual preference. Mercury rules the natural features of your consciousness and knowledge. The sun constellation is what we generally call a constellation.

Question 5: What's on Mercury? Is there water on Mercury?

Question 6: What are the mysteries on Mercury? The first mystery: the unknown reflective substance on the surface of mercury. In the image of Mercury's surface taken by Messenger, you can clearly see the bright, speckled impact crater. Without this high-resolution image, all this is still a mystery. The new mercury surface dual imaging system improves the resolution to 10 meter. At this level of resolution, the impact crater structure on the surface of Mercury with a diameter from several hundred meters to several kilometers will be extremely clear. At the same time, it is also found that unknown substances with high reflectivity appear around the impact crater, forming a halo on the image, which is not only distributed around the impact crater, but also around the central peak and the ring peak.

The above-mentioned unidentified reflection material is completely a new geomorphological feature, which is different from what scientists have observed on the moon and mercury in the past. Brett Denevi, a scientist at the Applied Physics Laboratory (APL) of Johns Hopkins University, said that through the discussion of the imaging management team of the Maryland Messenger detector, the age of the unidentified reflective material should be relatively late, which also indicates that there are certain volatile substances in the crust of Mercury, and this substance should be extremely rich.

The second mystery: the content of sulfur and other elements and volcanic activity. The X-ray spectrophotometer (XRS) carried on the signal is a tool, which is mainly used to detect the abundance of key elements of mercury. Through orbital survey, the average ratios of magnesium/silicon, aluminum/silicon and calcium/silicon in some areas on the surface of Mercury are unusually high, which is quite different from that on the surface of the moon, but there are basically no rich rocks on the surface of Mercury.

At the same time, XRS also found a large number of sulfides on the surface of mercury, which is consistent with the observation report of the ground observatory on mercury. This discovery shows that under the same conditions, the source of mercury surface sediments is much lower than that of other terrestrial planets, which is of great positive and potential significance to fully understand the influence of volcanic activity on mercury.

The third mystery: the mystery of mercury polar ice. At present, Messenger's Mercury laser altimeter has drawn a complete topographic map of Mercury's northern hemisphere through nearly 2 million orbital scans, and the large-scale geological structure and profile geological characteristics of Mercury's northern hemisphere are presented in high-resolution images. Through the study of the images, scientists found that the altitude of mountains or other geological features near the Arctic region of Mercury is generally low.

However, as early as 20 years ago, radar scattering images of planets on the earth showed that there were a lot of polar ice deposits in both the North Pole and the South Pole of Mercury. These deposits are mainly formed by liquid water under extremely cold conditions, and these ice deposits are mainly stored on the back side of polar impact craters. Because they will never be exposed to sunlight and the temperature is extremely low, these ice deposits can remain in this state forever. Messenger's new mission is to map polar impact craters using altimeters. Through the detailed detection of the impact crater, we can know the content of ice deposits in the polar regions of Mercury to some extent.

The fourth mystery: the mystery of the explosion of high-energy particles in Mercury's magnetosphere. As early as 1974, when Mariner X flew over Mercury for the first time, an important discovery was that Mercury not only had the same magnetosphere as the Earth, but also had frequent high-energy particle bursts. Mariner X had observed four high-energy particle bursts at the same time, but this led to a question: Why didn't Messenger detect such high-density high-energy particle bursts when it flew over Mercury for three consecutive times? Now that Messenger is at the perihelion of Mercury, its orbit will be modified. Judging from the current signs, the high-energy particle bursts in Mercury magnetosphere often have some unknown "timing" induction mechanism, which further casts a mysterious veil on Mercury magnetosphere.

Question 7: What are the characteristics of Mercury's atmospheric environment?

Mercury has only a small amount of atmosphere. Mercury has an extremely thin atmosphere. In fact, gas molecules in Mercury's atmosphere collide with the surface of Mercury more frequently than with each other. For these reasons, Mercury should be considered as having no atmosphere. The atmosphere is mainly composed of oxygen, potassium and sodium.

The atoms that make up Mercury's atmosphere are constantly disappearing into space, because the average life span of potassium or sodium atoms on a Mercury Day (a Mercury Day-half of its perihelion time) is about 3 hours. The lost atmosphere is constantly replaced by some mechanisms, such as being captured by planetary gravitational fields, volcanic steam, degassing of polar ice sheets and so on.

Temperature and sunshine conditions

The average surface temperature of Mercury is about 452K, ranging from 90 K to 700K, and it is the planet with the largest temperature difference. Comparing with the earth, the temperature change on the earth is only11k. (This is only solar radiation energy, regardless of "season" and "weather") The sunshine intensity on the surface of Mercury is 8.9 times that of the Earth, and the total * * * irradiance is 9 126.6W/m2.

Surprisingly, the radar observation of 1992 shows that there is ice at the North Pole of Mercury. It is generally believed that ice exists at the bottom of the crater that the sun never shines, and it is accumulated due to the impact of gas from the inner surface of comets and/or planets.

topography

Mercury's crater is very similar to the moon. One of the most striking features on the surface of Mercury (including only the photographed part) is an impact crater with a diameter of 1350km: Calorie Basin, which is the highest temperature area on Mercury. Mercury's topography is marked as undulating, because the cooling and contraction of Mercury's core caused the shell to wrinkle billions of years ago. Most mercury surfaces include two different age groups; Younger ones are relatively flat, probably because lava is immersed in earlier terrain. In addition, Mercury has "remarkable" and "periodic expansion".

The surface of Mercury is much like the moon, covered with craters, great plains, basins, radiation patterns and cliffs. 1976, the international astronomical union began to name craters on mercury.

Observing Mercury on the ground, you can hardly see its details. 1973165438+1On October 3, the United States launched the Mariner spacecraft 10 to fly close to Mercury. This is the only spacecraft that has visited Mercury so far. During three meetings with Mercury, it sent back more than 5,000 photos to the ground. For the last time, it was only 372 kilometers away from the surface of Mercury, and it took a very clear TV image of Mercury. Astronomers were surprised to find that the surface of mercury is very similar to that of the moon.

The surface of Mercury is littered with craters of all sizes, including mountains, plains and frightening cliffs. According to statistics, there are thousands of craters on Mercury, whose slopes are gentler than those on the moon.

Like craters on the moon, craters on mercury have names. Among the more than 3 10 craters named by the International Astronomical Union, there are 15 craters named after people of our Chinese nation. You Boya: Legend has it that he was a musician in the Spring and Autumn Period; Cai Yan, a poetess in the late Eastern Han Dynasty: Li Bai, a great poet in the Tang Dynasty; Bai Juyi, a great poet in Tang Dynasty, and Dong Yuan, a painter in Southern Tang Dynasty in Five Dynasties and Ten Countries; Li Qingzhao, a poetess in the Southern Song Dynasty: Jiang Kui, a musician in the Southern Song Dynasty; Kai Liang: painter of Southern Song Dynasty; Guan Hanqing: Yuan Dynasty dramatist: Yuan Dynasty dramatist Ma Zhiyuan: Zhao Meng: Yuan Dynasty painter and calligrapher; Wang Meng: painter at the end of Yuan Dynasty; Zhu Da: painter in the early Qing Dynasty: Cao Zhan (Cao Xueqin): writer in the Qing Dynasty; Lu Xun: a modern writer in China.

The names of craters on the surface of Mercury are the names of writers and artists, but there are no scientists. This is because most craters on the moon are named after scientists. The craters named on the surface of Mercury are all more than 20 kilometers in diameter, and they are all located in the western hemisphere of Mercury. The names of these celebrities will always compete with the sun and the moon to commemorate their outstanding contributions to mankind.

The topographical features of Mercury are as follows:

Craters-See the list of Mercury craters.

Albedo characteristics (identifying reflections from different areas)

Mountains-Please refer to the list of Mercury Mountains.

mountain range

Great Plains-View a list of Mercury Plains.

Cliffs-please refer to the mercury cliff list.

Grand Canyon-View the list of Mercury Canyon.

geologic structure

1. Crust-100c200km thick.

......& gt& gt

Question 8: What is on Mercury in the universe? Mercury is the closest planet to the sun and contains a lot of iron. The highest surface temperature is 634.5℃, and the lowest surface temperature is -86℃. Although it is called mercury, there is no water. Because there is no atmospheric regulation, the temperature in these places has been maintained at MINUS 280 degrees Fahrenheit (about-173 degrees Celsius). These craters, which Dr. Solomon called "deep freezing traps", may contain more water and ice than craters on the moon. Although there is still debate on this point, Professor Solomon said that this can at least prove that water is ubiquitous in the solar system, at least for molecular water. Of course, Neptune, Uranus, Saturn, Jupiter, Mars, Venus and Mercury all have no liquid water, but there are gaseous water and solid water, such as the moon.

Question 9: Mercury is mostly water? Is it? What kind of water is this? Is Mars all fire? Mars is not smart because of its high temperature. Have you thought of anything?