His eyes fell on the document in his hand, staring at the Mars atmosphere modification plan described by Xu Chuan, with strong interest in Academician Chang Huaxiang's eyes.
Terraforming Mars is actually a very complicated task.
For example, the improvement and reconstruction of the atmosphere does not mean simply transporting air from the earth to cover the surface of Mars, or stimulating the carbon dioxide inside the Martian soil to create a greenhouse environment.
Based on the current situation of Mars, even if they use various means to artificially create an atmosphere on the surface of Mars, it will quickly lose its ability to protect itself because of its weak magnetic field and gravity.
In particular, the lack of magnetic field is one of the key reasons for the disappearance of Mars' surface atmosphere.
According to astronomers' observations of Mars, Mars once had a much thicker and warmer atmosphere than it does now.
Although the thickness is not comparable to that of the Earth, it is still enough to ensure a warm environment on the surface of Mars and allow water resources to flow on the surface.
Today, Mars' atmosphere is only one percent as thick as Earth's.
The core reason is that the magnetic field of Mars has disappeared, so that the strong solar wind has blown away a large number of atmospheric molecules on the surface of Mars over the past few billion years.
It is estimated that about 1 million tons of gas are blown away by the solar wind every year, and this is still the current assessment of the situation on Mars by astronomers entering the 21st century.
If it were in ancient times, this speed might be even faster.
After all, the sun's activities were more frequent and violent in ancient times.
If you want Mars to have a living environment like the Earth, although it is important to reconstruct the atmosphere, it is more important to give Mars a magnetic field that can protect itself!
If the atmosphere is the protective umbrella of life, then the magnetic field is the protective umbrella of the atmosphere.
Only by allowing Mars to regain its magnetic field and have the ability to resist solar wind blowing and external radiation interference can the atmosphere be stabilized on Mars.
In other words, Mars' atmosphere and magnetic field must be constructed together.
It can even be said that restoring the magnetic field of Mars is the first step in transforming Mars.
Because only by restoring the magnetic field can the atmosphere and moisture of Mars be effectively protected from being stripped away by the solar wind.
Building or transforming just one of them will not be of much significance to the Mars terraforming project.
However, the problem of how to give Mars a magnetic field is no less difficult than rebuilding an atmosphere on Mars. It can even be said to be more difficult.
After all, this is a huge planet, and one can imagine how difficult it would be to transform it by human power.
Of course, there are ways.
If you want to construct a planet's magnetic field, you must know the source of the planet's magnetic field.
Take the home planet Earth as an example. The core of the Earth is composed of metal elements such as iron and nickel.
In the center of the earth, these iron and nickel will melt into liquid due to high temperatures exceeding 5,000 degrees Celsius.
When these liquid iron-nickel alloys move at the interface between the mantle and the core, extremely large currents will be formed due to the difference in rotational speed. The intensity of these currents is far higher than ordinary people's imagination, and the resulting magnetic field is enough to
It extends tens of thousands of kilometers into space to form the Earth's magnetic circle.
This is the current mainstream view in the scientific community on the causes of the formation of the Earth's core magnetic field.
If it's hard to understand, you can imagine the earth as a bearing, with the inner and outer rings being the earth's core and mantle respectively.
The ‘turning beads’ in between are the liquid iron-nickel alloy and other substances spread between the core and the mantle.
When the inner and outer rings of the bearing rotate at different speeds, the steel ball (liquid iron-nickel alloy) in the middle of the bearing will rotate, thereby forming energy (high-intensity current)
However, unlike the Earth, Mars has lost its magnetic field over the past few billion years due to the cooling of the Martian core and the reduced activity of the iron-nickel lava core.
As for the reason, humans may not know it yet.
It may be that billions of years ago, Mars did not suffer meteorite impacts on the same scale as Earth, which caused the temperature of Mars' core to drop too quickly.
Of course, it is also possible that on the contrary, the slowdown in the movement of the core of Mars was caused by a large-scale impact countless years ago.
However, for the current terraforming of Mars, how to reconstruct the magnetic field of Mars is the most important.
As for the method, in theory it is similar to reconstructing the atmosphere of Mars. There are two methods.
One is to use external force to block the attacks of solar wind and cosmic rays.
For example, placing magnetic satellites on Mars can shield the impact of solar wind on the Martian atmosphere.
The current solution recommended by the scientific community is to place a large artificial space station at the Lagrange point L1 between the sun and Mars.
The main function of the space station is an electromagnet, which protects Mars through the magnetic field generated by the electromagnet.
Alternatively, a set of normal-temperature superconducting devices could be built around the entire planet around the equator, north and south poles of Mars, and provide energy through a controllable nuclear fusion reactor to provide a shielding and protective magnetic field for the entire planet.
These are all methods of blocking solar wind and cosmic radiation by building equipment outside Mars to provide additional magnetic fields.
The other type still relies on Mars itself.
Just like stimulating greenhouse gases such as carbon dioxide, methane, and water vapor contained in the Martian soil to reconstruct the Martian atmosphere and body temperature.
The main means of reconstructing Mars' magnetic field can still be implemented on Mars itself.
Through research, investigation and exploration of Mars in recent years, the scientific community has confirmed that Mars, like the Earth, has a core composed of iron and nickel metal.
It's just that this core is no longer as hot and active as the Earth's core, which also means that the current intensity it generates during the convection process is not strong enough, and thus the magnetic field is not strong enough.
But as long as the metal core is present and has not completely stopped running, there are ways to make it 'active' again.
This chapter is not over yet, please click on the next page to continue reading! For example, by using large-yield nuclear weapons to shock the core of Mars and reheat the iron-nickel core of Mars.
Regarding this idea, I believe many people have seen similar operations in the science fiction movie "Earth".
In the movie, a mysterious force is hindering the normal operation of the earth, and the rotation of the core is about to stop.
In order to save the earth and save all mankind, scientists organized a special operations team. They planned to take an underground spacecraft to the center of the earth and detonate a special device there to ensure the normal operation of the earth.
Theoretically, it is indeed possible to destroy the core of Mars through nuclear weapons, causing it to remelt and generate a magnetic field.
However, this method is extremely difficult in actual operation because it requires drilling to very deep depths on Mars.
Even the diameter of Mars is much smaller than that of Earth, only about half that of Earth.
But for current human technology, it is still an almost insurmountable distance.
You must know that the deepest borehole ever dug by humans on the earth is the Kola Super Deep Borehole in Hongsu, with a depth of 12,263 meters.
And this depth, compared to the radius of Mars, which is close to 3,400 kilometers, is even superficial.
Therefore, the feasibility of this solution is relatively low, and it is far more difficult to implement than building equipment outside Mars to provide additional magnetic fields to block solar wind and cosmic radiation.
However, in the Mars transformation report in his hand, Xu Chuan also proposed two other directions for 'stimulating' the Martian magnetic field.
The first is the same as stimulating the greenhouse gases contained in the Martian soil, through large-scale bombing operations.
However, what is needed to activate the core of Mars is not nuclear weapons, but meteorites and asteroids of "moderate quality"!
That's right, by conducting detailed exploration of the gravity field of Mars and drawing a gravity map, supercomputers are used to calculate the traction pattern of Mars' crust. It can be confirmed how heavy the meteorite or asteroid is to accurately transmit the shock wave generated by the impact.
to the core of Mars.
Theoretically, it is entirely feasible to use the shock wave generated by a meteorite impact to guide the force to the core of Mars and make it active again.
And this plan is not the first time Xu Chuan has proposed it.
As early as the last century, when humans set foot in space and began to explore Mars, some people proposed this idea.
However, what is different from the meteorite impact in the Mars transformation report in his hand is that in the past, most solutions to restarting Mars' magnetic field were to impact Mars through one or several large enough planets to reactivate the metal core of Mars.
Purpose.
But the plan proposed by Xu Chuan is much more detailed.
Hundreds or even thousands of asteroids or meteorites of different sizes and weights will impact Mars in batches.
Shock waves from different directions are used, combined with the distribution of Mars' own gravity field, to pull the core and make the core operate again.
At the same time, water ice resources and water carried in asteroids and meteorites
It has to be said that this solution is far crazier than building equipment outside Mars to provide additional magnetic fields.
Because the current technology controlled by humans is still quite far away from having the technology to plan a "space crash" accident.
Although the asteroid belt between Mars and Jupiter can provide sufficient meteorites and asteroids, how to stop these asteroids, transport them to the vicinity of the orbit of Mars, and even make them accurately fall into the point where they need to be impacted is still a challenge.
It is a very difficult matter and requires solving various problems and technical difficulties.
Moreover, let alone capturing meteorites, it is currently difficult for humans to even recycle space debris in space.
Not to mention controlling meteorites to hit planets.
In addition, it is difficult to control the degree. If you use too much force and destroy the backup server of Mars, it will be even more troublesome.
Therefore, in summary, the idea of activating the core of Mars through meteorites impacting Mars is far less mature and appropriate than placing a large artificial space station at the Lagrange point L1 between the sun and Mars to shield the solar wind.
However, in Xu Chuan's transformation report, the impact of meteorites on Mars to stimulate the core also has another role.
That is to replace large-scale nuclear weapons to carry out a comprehensive saturation strike on the surface of Mars. In addition to activating the basic function of the Martian core, it also plays the role of releasing carbon dioxide, methane, water vapor and other greenhouse gases in the Martian soil.
In addition, the impact of a large number of meteorites and asteroids can pull the continental plates of Mars to a certain extent, causing slight displacement of the plates and activating volcanoes on the surface of Mars that had been dormant in the past.
Just like the asteroid that hit the earth that caused the extinction of the dinosaurs 67 million years ago.
In addition to the dust that the asteroid with a diameter of about 10 kilometers hit the earth and blocked the sky and the sun, the impact itself also affected the earth's plates and caused a large number of volcanic eruptions.
These large volcanic groups erupted a large amount of volcanic ash, carbon dioxide, water vapor, sulfur-containing compounds and other substances during this impact event.
For the earth, these are the main culprits causing the extinction of life.
But for the now desolate Mars, it will become an important milestone in the evolution of transforming the planet and making it habitable for life again.
They can greatly change the atmosphere of Mars and quickly replenish the thin atmosphere with various gases to a certain extent.
In addition to 'bombing' Mars with a large number of meteorites or asteroids, there is also a way to activate the Martian magnetic field by transporting a 'Ceres' or 'Cerris dwarf planet' to the orbit of Mars.
, as a companion star of Mars.
Just like the moon and the earth, theoretically speaking, the gravity of the large celestial body orbiting Mars can act as a mixer acting on the core of Mars.
This would melt and activate Mars' frozen core again, thus activating the Martian magnetic field.
And it can also act as a protective umbrella for Mars to prevent Mars from encountering too strong asteroid or meteorite impacts.
However, in this plan, Xu Chuan labeled it as too difficult and unlikely to be realized in a short period of time.
But he regarded this plan as an optional plan for continuing to optimize and transform Mars in the 'future'.
If technology has developed enough to control dwarf planets in the next century or centuries, then allowing Mars to have a satellite will keep its core young for hundreds of millions or even billions of years.
The key.
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PS: There will be another chapter later, it may be quite late, please get up in the morning and read it.