The dream of settling on Mars may be temporarily shelved due to the lack of water. Scientists initially hoped to use greenhouse gases to melt the polar ice caps of Mars to create an environment suitable for human habitation. However, the latest research has actually poured cold water on this ambitious plan.
A grand blueprint for terraforming Mars
The idea of transforming Mars into a second Earth has been around since the 1970s. Carl Sagan, a well-known American astronomy popularizer, first proposed this concept in 1971. NASA planetary scientists have since conducted in-depth research on its feasibility.
There are two core goals regarding the terraforming of Mars. One is to thicken the thin atmosphere, so that when humans carry out various activities on Mars in the future, at least they do not have to wear heavy space suits. The second is to increase the surface temperature, which is an average of minus 63 degrees Celsius, so that liquid water can stably exist.
For scientists, they discovered that there is a large amount of water resources in the form of glaciers on Mars, which are mainly distributed at the poles and underground. As long as the temperature is in the right state, the ice can melt and become a valuable water source, thus providing basic guarantee for human settlement.
The most valuable greenhouse gas on Mars
Greenhouse gases are a headache on Earth, but they are a treasure on Mars. Scientists plan to release the carbon dioxide stored on Mars to create an artificial greenhouse effect, while achieving the dual goals of thickening the atmosphere and raising temperatures.
Polar dry ice, carbon dioxide adsorbed in surface soil, and carbonate minerals, these three parts constitute the carbon dioxide reserves on Mars. If all of these can be released, theoretically speaking, it can greatly increase the atmospheric pressure of Mars.
But the question arises, can the overall amount of carbon dioxide on Mars really meet the demand? At 23:00 on July 30, Beijing time, a study published in Nature Astronomy gave a disappointing answer.
Polar dry ice is not enough
Carbon dioxide from the dry ice at the poles of Mars is extremely easy to obtain. During the Martian summer, the dry ice in the North Pole will naturally sublime and disappear. However, there are some non-continuous dry ice reserves in the Antarctic. Scientists have come up with various ways to accelerate this process.
In the Martian atmosphere, some people proposed to detonate explosives to raise a large amount of dust. This dust would cover the ice surface, thereby reducing the surface 's reflection of sunlight, thereby improving the efficiency of heat absorption. In addition, some people have a more direct idea: simply detonate the polar ice caps and let the dry ice sublimate in an instant.
However, calculated results show that even if all the dry ice at the North and South Poles is exhausted, it will only increase the air pressure by 0.015 millibars. This mere increase in pressure is only twice the current atmospheric pressure of Mars. It is still extremely far away from the atmospheric pressure value that humans need to achieve, as if it is separated by countless hundreds of thousands of miles.
Carbonate mining is too difficult
Carbonate minerals from Mars are a second potential source. When these minerals are heated to about 300 degrees Celsius, they decompose and release carbon dioxide. However, the question is, where does so much energy come from on Mars?
The largest carbonate exposed area discovered so far is in the Nili Plain. Carbonates in other places are either scattered scattered or buried too deeply, making it impossible to exploit them on a large scale. Scientists estimate that even if all that can be mined is mined, it will only increase atmospheric pressure by 0.012 bar at most.
Although this number is slightly more than polar dry ice, it is still extremely small. And to achieve this goal, the energy and project scale required far exceed the current technical capabilities of mankind.
Carbon dioxide in topsoil is unrealistic
There is a large amount of carbon dioxide adsorbed in the surface soil of Mars, so it seems that this is the most considerable reserve. According to calculations, if all the top 100 meters of soil were heated, the carbon dioxide released would increase the atmospheric pressure of Mars by 0.4 bar.
However, the amount of work involved in this plan is simply unimaginable. It needs to be heated to cover the entire surface of Mars, which is a soil layer hundreds of meters thick. Even if nuclear fusion technology is used, it will definitely take tens of thousands of years. The scientists then simply eliminated this option.
What's even worse is that even if some atmosphere is created after going through all kinds of difficulties, the solar wind will continue to strip these gases into space. Mars has almost no magnetic field protection, and atmospheric escape is a huge problem that cannot be solved.
Human technology is far from enough
The first scientist comprehensively analyzed all possibilities, and the second scientist also conducted a comprehensive analysis of all possibilities, and then concluded that under the best ideal conditions, the largest amount of carbon dioxide existing on Mars is that it can only increase the atmospheric pressure to three times. However, this three times the atmospheric pressure only accounts for one-fiftieth of the minimum standard necessary for human survival.
As far as the temperature is concerned, there is no better situation. It can only increase by 10 degrees Celsius at most. The average temperature of Mars is still far below the freezing point of water, and liquid water still cannot exist stably. Some people have suggested using meteorite impacts to replenish carbon dioxide. However, in order to do this, Mars would have to be riddled with holes.
Ultimately, with the current technological capabilities of mankind, it is completely impossible to achieve terraforming by relying on Mars' own local carbon dioxide. And such an inference poured cold water on those enthusiastic Martian immigrants.
If you see this, you will think whether it is still possible for humans to transform Mars in the future, or whether we should first focus on protecting this unique home of the earth. Welcome to leave your comments in the comment area to start the discussion, and give it a like so that more people can participate!
