Chinanews. com client March 14 th (Reporter Shangguan Yun) Recently, "1.8 billion pixel panoramic photos of Mars" boarded the hot search. The landform shown in the above photos has also attracted many people’s attention, and some people even began to discuss the topic of "immigration" to Mars.
Gao Shuang, a doctor of astronomy and a popular science writer, said in an interview with Zhongxin.com that Mars is a terrestrial planet and has always been an important goal for human beings to explore space.
Earth-like planets in the solar system
Gao Shuang mentioned that in the solar system, the terrestrial planets are arranged according to the distance from near to far from the sun, followed by Mercury, Venus, Earth and Mars.
Data Map: On March 5th, NASA announced the highest resolution panoramic photo of Mars ever taken by the Curiosity Mars probe. Image source: NASA official website
"Earth-like planets are very similar in size and internal structure." Gao Shuang explained that there is an iron core in the innermost part, the middle layer is the mantle, and the outer layer is a thin crust, which is also very strong. "It looks a bit like an apple, with three components: apple core, apple flesh and apple skin."
Of course, there is still a big difference between Mars and the Earth. Gao Shuang introduced that Mars is not only much thinner in air, but also short of water. "Mars is about half smaller than the Earth, and the distance is also very close. Every two years, there will be the closest moment between Mars and the Earth. This is also a good opportunity to launch a Mars probe. Our name is ‘ Launch window ’ 。”
"In theory, Venus is closer to the Earth in size and has a dense atmosphere. But the problem is that its atmosphere is too thick, like a thick quilt, making Venus the hottest planet in the solar system. " Gao Shuang said, and the pressure on Venus is extremely high, and there are scenes of volcanic eruptions everywhere, and the environment is very bad.
Why has Mars become the focus of space exploration?
Although they are all terrestrial planets, Mars always attracts more attention in space exploration.
The reason, Gao Shuang said, is that, first of all, Mars, with thin air and always sunny, is more likely to be "intimately contacted" by the detectors sent by human beings; In addition, there is an angle between the orbit of Mars around the sun and the plane where Mars rotates, and so does the earth.
Data Map: The high-definition picture of Mars released by NASA shows the face of the huge plains and sand dunes in the south of Mars.
Moreover, the angle between them is very close. Therefore, the temperature of Mars, like that of the Earth, can change periodically throughout the year. Gao Shuang mentioned that, more coincidentally, the time for Mars to make one revolution is very close to the rotation time of the Earth of 24 hours.
"That is to say, the length of a day on Mars is very close to that of the Earth. In this way, working on Mars is very close to the working environment in the Gobi Desert where the earth’s air is thin. Of course, the environment on Mars is much more severe. " Gao Shuang concluded.
In fact, the reason why Mars has become the focus of people’s attention is also related to a small misunderstanding in history. Gao Shuang told a story: When Italian astronomer Shapari used a telescope to observe Mars, he found that there were many gullies and ridges crisscrossing the surface of Mars, which he called "canali" of Mars. This means "ditch, river" in Italian.
"But when it was later translated, some people mistakenly translated it into canal, which means canal, implying artificial digging. After this misunderstanding spread, everyone mistakenly thought it was true, and raised a question about ‘ Martians ’ Curiosity. " Based on the above reasons, Gao Shuang thinks that Mars has always been an important goal for human beings to explore space.
Will there be life on Mars?
In fact, the topic of whether there is life on Mars has always been high.
"At present, the relatively certain result is that Mars was once rich in water, and the air was much thicker than it is now." Gao Shuang said that scientist concluded that it was an environment suitable for life several billion year ago.
"Now we can’t see the common animals and plants on the earth on Mars, and we can’t see the particularly rich traces of water flow, wind and frost erosion and corrosion." Gao Shuang said that some traces on Mars are very similar to rivers or lakes, which were water sources that existed billions of years ago and have now dried up.
Data Map: On July 25, 2018, in Rome, Italy, scientists held a press conference. Agence France-Presse reported on July 25 that the study found that the first liquid water lake was discovered on Mars. According to the report, scientists have discovered a huge underground aquifer on Mars, which has increased the expectation of life on Mars.
Moreover, having an environment suitable for life does not mean "having life", which are two different things. Gao Shuang said, "We can only guess that one possibility is that Mars once had life, and it completely disappeared with the change of environment; The second possibility is that even if there is a suitable environment, life has not been born. "
"Behind these two possibilities are two kinds of cognition of life. The former believes that life is a universal truth, and the emergence and development of life is an inevitable result. The latter believes that life is an accidental event and a precious grace that can be met but not sought. " Gao Shuang said, "I personally believe in the former."
Is it reliable to immigrate to Mars?
Because of the many similarities between Mars and the Earth, people will always ask the question: Is it possible to immigrate to Mars? Gao Shuang’s answer is no.
"The most direct reason is that the current environment of Mars is much worse than that of the Earth. Compared with the Martian environment, the earth is simply ‘ Paradise ’ 。” He gave an example, "About 70% of the earth’s surface is covered by deep oceans."
These oceans have become a huge "regulator" for stabilizing temperature and controlling humidity, and have bred a large number of marine life. Gao Shuang said that Mars will never have these factors.
"At present, even if you immigrate to Mars, it is only possible to build a laboratory in a small area to achieve indoor local climate regulation, and outside the door is a desert with sandstorms, hypoxia, low temperature and infinite dryness." Gao Shuang said.
However, Gao Shuang said, "We can also adopt this attitude towards Mars. While developing itself, aim at Mars, first establish a vanguard base and form a small environment … … Maybe one day, immigration will come naturally in the past. " (End)