Is it alive or poisonous? Bringing Martian soil back to earth is no joke, and the consequences are unpredictable.

Many people still remember that Mark planted potatoes on Mars in Star Rescue, and everyone has been coveting his potatoes for a long time! But the reality is that humans can bring back soil from the moon and samples from asteroids, but they have not brought back anything from Mars, even a grain of sand. Why didn't humans bring back soil samples from Mars?

In fact, scientists want Mars potatoes more than others. After all, it is related to the future survival of mankind. However, it is really unintentional not to bring them back to the Martian soil. There are many concerns and worries. If we act rashly, the unpredictable consequences are no joke!

Moreover, to bring back the Martian soil, we need to overcome three problems, one is technical, the other is biological and the third is safety, so let's look at these problems one by one.

One of the key reasons why humans can't bring back soil samples from Mars is that human technology can't return from Mars. Musk also said in his Mars plan that the first passengers who went to Mars never came back. In other words, it is no problem for a human-designed probe to go to Mars, but it is very difficult to come back.

Some people think it is impossible. Can come back from the moon, but also from further asteroids. Why can't they come back from Mars? This is because Mars is not on the same level as the moon and asteroids. It is a planet and a star, which is on the same level with the earth. We should not treat it with satellites and asteroids. Although Mars is smaller than the earth, its size is beyond the reach of the moon.

The gravity of an object on the moon is only one sixth of that of the earth (16.7%), while the gravity on Mars is 38% of that of the earth. Don't underestimate the gap above 10%. It is this difference that makes returning from the moon and returning from Mars are two different things. The moon is still within the gravitational range of the earth. To put it bluntly, it is within the earth's own system, but Mars belongs to a separate system, which is equivalent to cross-city and transnational, with different costs.

If we want to get rid of the gravity of Mars, we must spend a lot of energy and provide enough thrust to reach the first cosmic speed of Mars. Moreover, the distance from the earth to Mars far exceeds the distance from the earth to the moon, and the detector didn't carry that much fuel at all.

This is because if you come back with enough fuel, the load of the whole spacecraft will be seriously exceeded, and it will be full of fuel. So where did you put the probe and rover?

Therefore, even if humans collect soil on Mars, they can't send it back, which is the lack of hardware facilities. Human technology will progress. When one day we can overcome the fuel problem, can we bring Martian soil back to Earth? The answer is no, because there is still a biological problem that human beings need to solve.

Conquering technology is only the first hurdle facing mankind. What really worries scientists is whether there is unknown life in the soil of Mars. We just think that there is no life on Mars under the existing evidence, but no one can completely deny the existence of life on Mars.

The definition of life is very broad, from advanced creatures like us to life without cell structure like viruses. Mars has a large surface area, and human exploration of it is only a few percent. It is impossible to determine whether there is no life on the whole of Mars. It can only be said that the part of Mars that we have explored so far is lifeless.

Virus is a strange living body, which can realize the transformation between organism and "abiotic". When there is no host cell, virus will hibernate. Note that this kind of dormancy is not the kind of dormancy that humans understand to sleep, but the virus does not show activity, which is no different from inorganic substances. Generally speaking, dormant viruses are not infinite. When the outside temperature is too high, dormant viruses will also be eliminated.

Generally, the lower the temperature, the longer the virus sleeps. The average annual temperature of Mars is around 60 degrees below zero, so the virus may exist in such an environment for a long time. So how did the virus on Mars come from? This has to mention the past of Mars.

According to the image data sent back by the rover, people found that the landform of Mars is very similar to that of the earth, especially the canyon. Many people will think that the canyon is nothing special, but it is actually wet. The formation of canyons is inseparable from the erosion of boiling water. If Mars had no water, it wouldn't have such a topographical structure.

Water is considered as the source of life, and Mars in the past probably gave birth to early life like the Earth. The mass of Mars is smaller than that of the earth, and its ability to bind the atmosphere is weaker, resulting in that Mars has never formed a decent atmosphere from beginning to end.

Without the protection of the atmosphere, the water of Mars is directly exposed to the sun's radiation and decomposed into hydrogen and oxygen. This process lasted for a long time, and scientists were not sure when the last drop of liquid water on Mars disappeared. It is even possible that liquid water did not completely dissipate, but moved to the crust of Mars.

It is unlikely that aliens will live on Mars, but there may be dormant viruses on Mars. These viruses are likely to be completely different from those on earth.

So the third question that we can't rashly bring back Martian soil samples is, how to ensure that these soils are safe?

Because the virus on Mars is likely to be completely different from the virus on Earth, it is impossible to find it completely only by the detection of rovers and detectors. As long as there is a fish that escapes from the net, it is possible to come to earth. I'm afraid that at that time, the soil of Mars was not full of potatoes, but aliens!

In addition to biological hazards, Martian soil itself may also be highly toxic. Because there may have been an ocean on Mars, we all know that the water in the ocean is not drinkable. In addition to containing a lot of salt, there are many minerals and heavy metal ions that will not be decomposed by water.

This is equivalent to evaporating seawater, leaving behind crystals, which may be the case in the soil of Mars. Because of the disappearance of water, those substances in the past remained in the soil. This is a concentrated substance, just like the soil in salt lakes, which may contain highly toxic substances.

Some people think that human detection technology can't detect toxic things. As long as the soil on Mars is detected layer by layer, they don't believe that it can't be detected! The problem is that human detection technology is no problem for most substances and creatures on earth, but there are more substances in the universe than those on earth. Can humans guarantee that their technology can detect all substances? At least now humans dare not say so.

Since we can't guarantee that the soil we brought back is 100% safe, why take such a big risk? After all, human beings are afraid of unpredictable consequences. For the present situation, it is a wise choice not to bring back Martian soil.

There are so many uncertainties in Martian soil, does it mean that humans will never bring it back? Of course not. If this difficulty knocks us down, then we are not human beings!

As early as 1975, after Viking 1 successfully landed on Mars for the first time, people always hoped to establish a base on Mars as a springboard for human beings to move into space in the future. Then the vigorous "Biosphere II" experiment ended in failure, but it did not weaken the public's yearning for Mars at all, and then the film and television works with the theme of Mars emerged one after another.

Do we know that Mars is dangerous? Yes, otherwise it is impossible to get back the soil samples from Mars now. So will we give up? Of course not. Since 1960, when the Soviet Union first sent a probe to Mars, human exploration of Mars failed half the time. If humans had given up at that time, there would not be today's rover, let alone let humans see the landform of Mars clearly.

The soil brought back to Mars is difficult and dangerous for human beings now, but human beings will not stop there, and technology can be overcome, whether it is space flight or exploration. It just takes generations of efforts and a long wait.