In this paper, I participated in the series of solicitations of the great astronomy and Astronautics of Recordunkown science
It’s autumn now. Although the temperature is still very high, it’s cool compared with the high temperature in summer. Winter is coming after autumn, and winter is also the coldest season in the four seasons of the year. Although the global temperature is rising and winter is not as cold as it used to be, in some northern regions, winter is still too cold for people to bear.
Maybe in the eyes of many people, 20 degrees below zero is cold enough, but you can’t feel the real cold in the world. As we all know, there is no upper limit for the temperature. It can be several hundred degrees, several thousand degrees, or even hundreds of millions of degrees. However, there is a lower limit for the temperature, which is 273.15 degrees below zero.
Of course, this absolute zero is a lower limit of temperature, which, like the speed of light, can only be infinitely close and can not be reached. The reason is that the movement of atoms cannot stop completely. On the earth, the place that can reach close to absolute zero is the laboratory. By compressing liquid nitrogen, scientists can make the temperature infinitely close to absolute zero. This temperature is used to freeze the human body, which is an important application of science and technology in the future.
Although only laboratories on earth can achieve infinitely close to absolute zero, it is totally different in the universe. The background radiation temperature of the universe is very low, reaching minus 270 degrees Celsius. Therefore, the universe is an extremely cold space. So where is the coldest place in the universe? Perhaps in the view of many people, the coldest place in the universe should be the interstellar space far away from stars and heat sources.
Interstellar space is the space between galaxies. It is far away from the light and heat of stars and Galaxy clouds. There is basically no ray of light or radiation. It is a dark existence. The atoms in interstellar space are almost too cold to move, so it should be the coldest place in the universe. But this is not the case.
According to the observation and research of scientists, the coldest place in the universe is not in interstellar space, but in a nebula. What’s the matter? This nebula, called the dart nebula, is located in the Milky Way galaxy, about 5000 light-years away from the earth, with a scale of 2.1 light-years. It is the coldest place in the universe so far. The temperature here is only half centigrade higher than absolute zero, as low as minus 272.5 centigrade, which is infinitely close to absolute zero.
Why does this happen? Nebula is the place where stars, planets and all kinds of gas and dust gather. There are many heat sources and thermal radiation. How can it become the coldest place in the universe? In fact, many people have a misunderstanding about the cause of cold. They think that the coldest place should be far away from the heat source, but they ignore a more important reason, that is, flow.
What is the lowest temperature on earth? Not far from the sun, but when the cold wind comes. Especially in winter, if there is no wind, we will not feel much cold, but if the cold wind comes, the temperature will drop sharply. And some cold places are often some tuyeres. For example, there is a place in Shanxi called yangfangkou, which has been an important place outside the pass since ancient times.
The special geographical form makes yangfangkou a tuyere, so it’s often windy here, especially in winter. The chilling wind makes the temperature here very low. The reason why the dart nebula is the coldest place in the universe is related to its special structure.
The dart nebula is a pre planetary nebula, which is equivalent to being in the middle stage of the star death process. It is formed by the rapid expansion of gas and dust from the aging star in its center. At this stage, the outer material of the star is constantly blown away, and the two poles of the star are still ejecting. Its gas emission speed reaches more than 100 kilometers per second, which is relative to the loss of two Neptune weight gas per second.
Moreover, the structure of the dart nebula is similar to a trumpet shape, with a small mouth and a very small gas discharge speed. In this case, the air is rapidly squeezed out to do work, resulting in adiabatic expansion, which accelerates the cooling of the air. So it’s the coldest place in the universe ever found. It can be seen that the coldest places in the universe are not the interstellar space far away from the heat source, but the nebulae with special structure.
Although scientists have found the coldest place in the universe is the dart nebula, it is still unknown whether there will be new places in the future to break the record. We should know that the universe is vast and vast, and the area that human beings can explore is very limited. With the rapid development of human science and technology, the future observation technology will also continue to improve. Maybe colder places will be found in the deeper stars. It is possible to break the temperature of minus 272.5 degrees Celsius and have a lower temperature.
It is not entirely impossible that there may be such a temperature as absolute zero somewhere in the universe. Moreover, the lower limit of absolute zero is also proposed by human beings under the current level of science and technology. It is also unknown whether it is an eternal truth. Maybe in the future, it is possible that there will be a lower temperature. At that time, minus 273.15 ℃ will no longer be the lower limit of temperature, but will be replaced by a lower temperature.
Of course, for the coldest dart Nebula in the universe, we can only observe it through astronomical telescopes. The distance of 5000 light-years is still a distance that human beings can’t cross. It is possible that in the future, humans will have the ability to fly faster than light. Maybe we can go into the interior of this nebula to observe and study, and find out more reasons for its low temperature.
Guys, what do you think of this? Welcome to leave a message below to discuss and express your opinions.