What is the amazing natural phenomenon?
The border guards of country A were puzzled when they saw this scene. Some people want to know: are all the crew asleep, or ... they boarded the ship carefully, and sure enough, all the crew were prone in different places. Someone shouted loudly, but no one answered. Someone put his hand into the crew's nose and mouth and found that he was not breathing, touching his chest and having no heartbeat. Oh, they are all dead!
The border guards immediately reported the matter to the relevant departments and asked the forensic doctor to find out the cause of death. The doctor examined all the dead carefully and found no symptoms of trauma or poisoning. Doctors believe that the death of crew members is very similar to the death of people who have a heart attack. But on second thought, is this possible? The answer is obviously no. Because these crew members will never die of heart disease at the same time. So what is the cause of this tragedy? This question has not been answered for a long time. So this sea tragedy that shocked the whole world added another layer of mystery to the world.
It is really "a wave is not flat, and a wave rises again." Then one day, someone traveled to the Boradri Cave in Hungary. As soon as he stepped into the very narrow passage in the cave, he found three bodies of unknown origin lying on the ground. Scared the tourists into tears, and hurried back to report. After verification, it was found that the deceased were three travelers. But the doctor did not find any signs of murder or suicide from the deceased, nor did he find out the cause of death for a long time.
With the development of modern science and technology, these two "mysteries" were finally solved by scientists, and they were both cases of invisible "murderers"-infrasound. The Malacca Strait tragedy was caused by the high-intensity infrasound generated by the storm in the ocean. Three travelers in the cave died of infrasound caused by sudden change of air pressure.
Infrasound is a kind of low-frequency sound, and the frequency of human language is generally between 300-5000Hz. Sound frequencies above 20000Hz are called ultrasonic waves, and sound frequencies below 20 Hz are called infrasound. Ultrasound and infrasound can't be heard. Infrasound has strong penetrating power, and its propagation speed in the air can reach more than 1200 km per hour. Infrasound energy makes people restless, depressed and even insane. Infrasound can also cause dizziness, vomiting, nausea, spasm or numbness of limbs. High-intensity infrasound below 7 Hz is fatal to human body. For example, in a infrasound research institute in France, a technical error caused infrasound to leak out, causing all 30 innocent residents ten miles away to die instantly.
Why does high-intensity low-frequency infrasound cause death? In the final analysis, it should be said that it is "* * * vibration". Muscles and internal organs of human body have their own natural vibration frequencies. When this lower natural frequency is the same as that of infrasound, it will produce * * vibration, which will produce greater amplitude and energy, thus causing great damage to human structure and death.
Infrasound waves in nature come from many aspects, such as solar magnetic storm, meteor impact, storm, sea roar, volcanic eruption, lightning and so on. Various artificial mechanisms can also become secondary sound sources, such as atomic bomb explosion, launch vehicle launch, blower, vacuum pump, diesel engine and so on.
Therefore, while preventing noise from polluting the environment, people must also pay attention to preventing the harm of this inaudible infrasound to human body.
2. Mirage Penglai County, located in the north of Shandong Province, has been known as "Penglai Wonderland" since ancient times. In ancient books, Penglai is called the sacred mountain on the sea, and the legendary "Eight Immortals Crossing the Sea" is here. Qin Shihuang came here to seek the sea gods and the medicine of immortality. Of course, these are all myths and legends, but they are directly related to the charming scenery of Penglai and the wonderful sight of a mirage.
There is a Ya Dan in the north of Penglai County, with steep mountains and surrounded by the sea on three sides. The famous Penglai Pavilion stands on the top of the mountain and climbs into the attic, which is an ideal place to watch the wonders of a mirage.
The so-called mirage is that at the turn of spring and summer or at the end of summer and early autumn, whenever it rains in Chu Qing, or it's half cloudy and half sunny, wonderful phantoms like pavilions, rolling mountains, trees and pedestrians suddenly appear in the air in the open sea, just like being in a fairyland. After a while, the phantom suddenly disappeared without a trace.
In fact, a mirage is a mirage, which is caused by atmospheric optical phenomena. In spring and summer, the temperature of sea water is relatively low during the day, and the lower air is colder and denser than the upper air, but the upper air is less dense. When sunlight passes through this air layer, it will be refracted and reflected. The dense air in the lower layer is like a mirror, reflecting the scenery on the ground in mid-air. There will be wonderful and illusory scenery. For example, in miaodao islands, north of Penglai County, the sea water temperature is low in summer and the air density varies, so Penglai County can often see the phantom of miaodao islands. Shen Kuo once recorded in the Song Dynasty: "There are clouds in the sea of Dengzhou (now Penglai), such as palaces, Taiwan, city figures, chariots and horses, which are vividly visible." Because people couldn't explain this phenomenon at that time, Penglai was associated with "Wonderland".
Mirages can be seen not only at sea, but also on rivers or deserts. But the illusion in the desert is not in mid-air but on the ground. This is because the air temperature near the ground in the desert during the day is higher than that in the upper layer, so the density of the upper layer is high and the density of the lower layer is low. The high-density reflector on the upper floor reflects the blue sky, trees and houses on the beach to form a reflection, so the blue sky is like a lake, which makes many desert travelers deceived.
No matter what kind of mirage, it can only appear in windless or weak weather conditions. When the wind blows together, the illusion suddenly disappears. This is because this air layer is extremely unstable. When there is a strong wind, the air in the upper and lower floors is stirred and mixed, and there is no difference in air density between the upper and lower floors, so the light will not be refracted and reflected.
The secret of "Wonderland" has been exposed, but people are not disappointed. Seeing a mirage is still a kind of enjoyment that people yearn for. What people yearn for more is Penglai's "fairyland" on earth, because Penglai itself has beautiful scenery. Penglai is surrounded by mountains and waters, with beautiful scenery. There are ten scenic spots, such as Feixian Pavilion in the sky, Mirage, Wan Li Chengbo, Lion Cave Cloud, Sunrise Fusang and Evening Tide Crescent Moon.
3. The protagonist of The Journey to the West's classic fairy tales, Tang Yan's master and apprentice, met many monsters on the way to learn from the West. These monsters often appear and disappear in strange smoke. Tang priest and his disciples strayed into the magic cave, and there was a terrible roar and demon smoke everywhere. ...
So, in nature, is there such a terrible strange fog between mountains? It seems that this is not a figment of The Journey to the West author Wu Cheng'en's imagination. Although this mysterious natural phenomenon is rare, it still exists.
Alaska is a volcanic area. Augustine volcano and Katmai volcano are active volcanoes in this area, which are famous for their frequent eruptions. 19 12 After the eruption of Katmai volcano, scientists went to investigate. At about 10 km northwest of this active volcano, they found a zone with a width of 8 km, a length of about 16 km and an area of more than 100 square km, which was covered with volcanic ash and covered with thousands of spray holes, with a row as long as 1000 meters. Accompanied by the terrible thunder, the nozzle kept spewing hot air mixed with volcanic ash into the sky. Driven by the high-pressure airflow, the gas roared down the valley at a hurricane-like speed, knocking down all the trees along the way with thunderous force. Like a demon, frightening and frightening. In the upper part of the valley, the smoke column is more dense, which makes the valley completely covered with smoke, so geologists call it "valley of ten thousand smokes"
Of course, not all strange smog is caused by volcanic activity. There is a strange smoke rising from the ground in Gangcheng tin mine area of Nandan Mining Bureau, Hunan Province, China. The smoke column is as high as 100 meter, almost touching the foot of the cloud, covering an area of nearly 3 square kilometers. Why does this strange smoke rise? Relevant geologists have conducted investigations and proved that this is caused by spontaneous combustion of coal seams. Thick smoke was ejected from three "magic holes" with a diameter of10m and a depth of about 20m. The smoke is white and the inside is yellow.
The spontaneous combustion of this coal seam has lasted for 9 years, and the highest temperature at the smoking place can reach 196℃, which is the highest fire area in China at present. People tried to put out the underground fire by sealing irrigation and other measures, but the effect was little and the fire was never controlled.
The most common strange smoke in the mountains is caused by spontaneous combustion of coal seams in the mountains. The Tang Priest and his disciples traveled westward along the ancient road in Xinjiang, passing through the flaming mountain area in Turpan, and the strange smoke produced by spontaneous combustion of coal seams could be seen at any time. Spontaneous combustion of coal seams often lasts for decades or even hundreds of years, which makes some areas smoke all the year round. It is really a veritable "fire of hell". When Wu Cheng'en was writing Journey to the West, he might get inspiration from this mysterious spontaneous combustion phenomenon, and connect it with monsters, so as to increase the mystery when monsters appear, and thus add some luster to those immortal chapters that are told by the world.
4. The Mystery of Rainbow In summer and autumn, after a heavy rain, a magnificent and colorful Changhong often appears in the sky. It flies on the horizon, like a splendid half-arch colored bridge, forming a magnificent illusion in the sky.
In ancient times, many myths and legends appeared because people didn't understand the reasons for the formation of rainbows. Some people say, "Rainbow is a bridge that the gods cross in the sky and sky of Tianhe". Some people say, "Rainbow is God's wand and whip." The Arab said, "Rainbow is a bow that god of light Gusha Shah put on the clouds at rest." Others said that "the rainbow is the smile of the goddess of joy" and "Chang 'e waved her long sleeves in the moon palace" and so on.
1624, Italian scholar Bishop Minnis explained the formation of rainbow with the principles of natural science. However, due to the backwardness and ignorance of society at that time, Bishop Minnis was expelled from the church, sentenced to death, and his works and bodies were burned together. Later, Descartes, a French scientist, saw an artificial rainbow with a lot of water drops in the air by the pool. He experimented with glass balls filled with water and published an article on the formation of rainbows in 1637. He said in the article: "Rainbow is the result of sunlight reflecting and refracting into water droplets in the air." But he still doesn't know how the color of the rainbow is formed. It was not until160 that Newton discovered the dispersion phenomenon of sunlight passing through a prism that the secret of the rainbow was uncovered.
Rainbow is a natural weather phenomenon. In midsummer and early autumn, before and after the rain, when there are many small water droplets floating in the air, when the sun shines on these small water droplets, due to refraction, the scattering of solar light is changed, making them become seven colors again; After reflection from the ground, a beautiful and bright arc of light is formed from the outside to the inside, arranged in the order of red, orange, yellow, green, cyan, blue and purple. This is a rainbow. The color and width of the rainbow are related to the size of water droplets. The bigger the water drops in the air, the brighter the color of the rainbow and the wider the ribbon. The smaller the water drop, the darker the rainbow and the narrower the ribbon. The appearance of rainbow is closely related to the local weather changes in the future. The weather proverb "The sun shines in the east and the rain falls in the west" summarized by the working people in our country is scientific. In the temperate zone where we live, the upper air flow moves regularly from west to east. Therefore, the change of weather in the future is closely related to the nature of airflow in the west. "East Red Sunrises" means that when a rainbow appears in the east in the evening, it indicates that it will be sunny the next day, because East Red means that although there are many water drops in the air in the east and the humidity is very high, the rain area will continue to develop eastward without passing through the local area, so it won't rain there. The corresponding dry air from the west will move to the local area, so it will be sunny the next day. "Rain on the rainbow in the west" means that a rainbow appeared in the west in the morning and it is going to rain soon. Because there are a lot of water droplets in the western sky, these water droplets will develop eastward and move to this area. In addition, with the rising of the local sun, evaporation intensifies, and the water vapor at low altitude rises to high altitude and meets the water droplets at high altitude, which makes the water droplets at high altitude expand and increase, which is easy to cause rainy weather. It is raining. There is a mountain at the junction of Yunnan and Myanmar in the southwest of China. The name of the mountain is "Gaoligong Mountain". This mountain is tall and big. At the foot of the mountain are the Nu and Lisu people in China. The brotherly people have good weather and good harvest every year here, which is really "the right place and the right time"! People here can live such a life of peace and contentment, not only enjoying the warmth of the big family of the motherland, but also benefiting from the "gift" given by this mountain. In other words, this Gaoligong Mountain is born a little special, which is different from other mountains.
This Gaoligong Mountain is lush from the foot of the mountain to the middle of the mountain. According to the height of the mountain, different trees grow here, one layer at a time, and the layers are different. Looking up again, it is snow-white Xuefeng, locked in there by frozen snow.
In the valley at the foot of the mountain, it is another scenery, where lakes are dotted. Yingying Lake ripples all day long, patting the shore of the lake, like a loving mother patting a sleeping baby; The lake is blue as blue, and the bottom of the lake is clearly visible; The shore of the lake is covered with flowers and green grass. The lake color contrasts with the mountain scenery, which is unusually beautiful. The farmland in the mountain village is irrigated by the water from these lakes, which is very convenient. In this way, there has never been a drought here. Harvest every year, people live and work in peace and contentment.
At this point in the story, readers are bound to ask questions: "The water stored in the lake will run out one day. What should I do? "
There is no need to worry about this. People there will rely on this magical Gaoligong Mountain to solve the water source in the lake.
Yes, every year from January to July and August, young people here go to the lake in droves to stand by and watch, holding hands and shouting loudly at the blue sky several times. A few minutes later, the clear sky is like magic, full of dark clouds rising from the sky, while the place near the ground is a mist with a thick fog. Soon, a gust of wind blew like a gust of wind, followed by pouring rain. However, after more than half an hour, it seems that the computer automatically controlled it, the wind and rain stopped on its own, and the water in the lake was full again. People there solved the water source in the lake in this strange way.
Why can people give orders!
It turns out that July and August are the rainy season in Gaoligongshan area, and the air is wet and hot. These hot and humid air accumulated in the valley. However, at the top of the mountain, the air looks dry and cold because the snow and ice closed the mountain there. Usually, the hot and humid air and the dry cold air here live in peace and quiet, like sleeping. However, when people shout, the sound waves emitted by the sound reverberate in the valley, and the sound waves oscillating back and forth stir the hot and humid air and dry cold air. Once hot and humid air meets dry and cold air, they seem to have fought a war and become dark and rolling clouds. Then there is a strong wind, and then there is a downpour. The ethnic minorities living there make use of this special geographical environment to benefit the people.
6. Aurora in the northeast of China and in the north of Heilongjiang, sometimes on quiet nights, a red velvet curtain naturally appears in the vast sky. Just when people were shocked, it suddenly turned into a blue meadow. It sometimes swims like a python and sometimes runs like a horse; Or like Shan Ye's huge fire, swords and shadows, and changing flags; Or like the gods opening their eyes, shooting flames and peeking at the world ... people call this strange scene in the night sky aurora.
1June 1982 18 10, such auroras were observed in Heilongjiang and western Jilin, as well as in Inner Mongolia and northern Hebei. Not far from the horizon of the northern sky, a semi-circular milky white light curtain of the size of the moon first appeared, and then the light curtain gradually expanded to the northeast. 10/5 minutes or so, forming an arc-shaped light curtain with bright edges and dark middle, and no stars can be seen in the light curtain. Then, the arc-shaped light curtain continues to expand and the brightness becomes dark. At 10: 30, the light curtain is the largest, accounting for about 1/5 of the sky, and the stars in the light curtain can already be seen. At about 10: 50, most of the light curtain disappeared. At about 10: 58, the light curtain all disappeared.
Aurora also appears in other parts of the world. In the northern hemisphere, the areas with the best chance to see the aurora are northern Alaska, northern Canada, northern Iceland, northern Norway and southern Novosibirsk Islands. In contrast, the northern part of Heilongjiang Province in China has fewer opportunities to see the aurora than the above-mentioned areas, mainly around March and September, that is, around the vernal equinox and autumnal equinox.
Aurora is one of the most spectacular natural phenomena on earth, but it has powerful destructive power. During the auroral burst, the ionosphere was seriously disturbed, which destroyed the propagation of short-wave radio signals. At this time, communication and traffic will have a serious impact. For example, in the United States, a taxi driver in Alaska received an order from a dispatcher in New Jersey in the east of the country during the intense activity of Aurora. At the same time, false images may suddenly appear on the screen of the early warning radar monitoring the plane crossing the polar regions, thus giving an alarm. At the same time, the constant change of aurora may induce strong current in slender conductors such as power lines, telephone lines and oil pipelines. Affected by induced current, oil pipelines may be seriously corroded. 1972, an aurora blew up a 230,000-volt transformer in Colombia and triggered a high-voltage transmission line from Maine to Texas.
How are colorful and powerful auroras formed? In the past, scientists usually thought that once captured by the earth, high-energy charged particles from the sun would be controlled by the earth's magnetic field, spiral down to the earth's magnetic pole along the magnetic field lines, and then collide with the low-density upper atmosphere there to emit light. Or the sun appears sunspots, flares, prominences, etc. , and the material that constitutes the sun continues to have a strong nuclear reaction, releasing a lot of energy. The sun ejects a large number of charged particles, such as protons and electrons, into space. These charged particles, like the giant wind from the sun (commonly known as "solar wind"), rushed into the range of the earth, and due to the effect of geomagnetic field, they concentrated and landed in the high altitude near the north and south poles, and various gas atoms and molecules in the upper atmosphere were excited by these charged particles, resulting in luminescence. Then according to this explanation, the aurora should appear in the form of a "glow spot" above the magnetic pole. However, this is not the case. Aurora does not appear in the form of "glow", but in the form of an irregular elliptical ribbon illusion over the polar regions. This situation can not help but make people doubt the previous general explanation. What's going on remains to be studied.
7. Wonderful False Sun 1985 1 3rd of the month 1 1, a spectacle in the atmospheric light image appeared over Suihua City, Heilongjiang Province. On this day, Suihua City was shrouded in a thin cloud like silk gauze. Around 1 1 point, a wonder appeared in the sky: the sun's disk was red. Golden edge, brilliant and dazzling; There is a 46 halo and a 22 halo around the sun. There are two "little suns" on both sides of the sun. A big white semicircle halo runs through four "little suns" and the sun. The four "little suns" are very bright, flashing colorful brilliance, just like a few pearls on a necklace. In the north of 22 and 46 halos, there is also a colored arc tangent to it and protruding towards the sun. Both arcs are blue inside and red outside, which is dazzling.
Why are there "five suns" in the sky? It turns out that one is a true sun, and the other four are false suns, which are called "false suns" in meteorology. Holidays are the highlights of sunlight passing through different forms of ice crystals. Such bright spots often appear symmetrically, sometimes as many as seven or eight. Because there are strict requirements on the position of light entering and leaving the ice crystals and the shape of the ice crystals when several holidays are formed, there are few holidays, and even fewer holidays. The relationship between the optical path formed by various holidays and the shape of ice crystals is also very complicated.
1September, 933 13, American scholar Syaber took a group of rare photos when he was watching the sunset at a higher latitude on the west coast of the United States: a big red sun slowly set in the west, and began to change from round to oval, and then from oval to steamed bread, with a round top and a flat bottom. Gradually, the upper part of the sun flattened, and finally four angular corners appeared, becoming a rare square sun. This set of photos aroused great interest. It has been cited as valuable information for half a century.
This "square sun" is formed by the refraction and reflection of sunlight when it passes through the atmosphere with different upper and lower densities. In polar regions and high latitudes. The temperature of land and sea surface is often very low, and the temperature in the near layer is lower than that in the upper layer, thus the phenomenon of "atmospheric inversion" appears. The air density near the ground or sea surface is high, but the density decreases as it goes up. When sunlight near the ground or sea surface passes through this low-altitude atmosphere, it will be refracted. As the sun sinks, this refraction obviously causes the light to bend to the earth side, so part of the light under the sun is extremely deflected, making its lower side as straight as a knife and becoming a straight line parallel to the horizon. As the sun sets, its upper part gradually deflects light. When reaching a certain height, the upper and lower edges of the sun are refracted into straight lines, forming a wonderful "square sun". The "square sun" can only be produced in the windless and cloudless air in the polar regions and high latitudes without strict weather conditions such as ice crystal fog, so it is rare.
1On the evening of July 20th, 979, a Polish sailboat "Morning Star" sailed through Polynesia from San Francisco via the equator and entered the waters west of Samoa. Suddenly, a helmsman flashed a dazzling green light like emerald, and he shouted excitedly, "Come and see! Over there, the sun is green! " However, when people look in the direction he pointed out, they only see the afterglow of the sunset as usual. How can there be a green light?
However, the appearance of the sun's green light is indeed possible, but only for a short time. In Egypt and Adriatic Sea, you can see green light at sunrise and sunset almost every day. Generally at dusk, as long as the horizon is clear and there are no clouds on the sea, green light will definitely appear. It is said that the pictures found in the pyramids of Egypt 6000 years ago depict the brilliant sun with green light.
Green sunshine is also the "magic" that the sun and the atmosphere play for us. The sunlight we usually see is composed of seven monochromatic lights: red, orange, yellow, green, cyan, blue and purple. However, due to the uneven density distribution of the upper and lower layers, the air becomes thinner as it goes up, so it is like a "gas prism" with upward edges and corners. When sunlight passes through, it is refracted and dispersed and decomposed into seven kinds of monochromatic light. However, the dispersion caused by this refraction is most obvious only when the sun's altitude angle is very low, that is, the sun is close to the horizon and the sunlight passes through the thick atmosphere almost horizontally. At this time, sunlight is decomposed into seven colors of monochromatic light. Because the wavelength of red light is the longest and the angle of refraction is the smallest, as the sun sets, red light first sinks below the horizon; Then the orange light and yellow light also disappeared under the horizon, while the green light, green light, blue light and purple light remained on the horizon. Because the wavelengths of green light, blue light and violet light are all relatively short, when they pass through the thick atmosphere, they have become very weak due to the strong scattering effect of dust in the atmosphere, and we can hardly feel them with our eyes. Only the green light is strong enough to reach people's eyes, and it is particularly dazzling, forming the spectacle of "green sunshine". Because green sunlight appears in a short time between sunrise and sunset, its existence time is very short, generally only 3 seconds, and the shortest is less than 1 second.