Why can't humans bring Martian soil back to Earth? What are you afraid of?

Many people, like me, may want to look for microorganisms or hidden small creatures in Martian meteorites or soil. What will alien life be like?

But many people are as disappointed as I am.

Man's exploration of Mars began with Mariner launched by the United States in 1964 and ended with Man Garian launched by Indian in 20 13. From the initial understanding that Mars is a lifeless desert planet, it was once a livable planet covered by the ocean about 4 billion years ago. In 20 18, methane, liquid water and seasonal changes were also found on Mars ... but no organisms or microorganisms were found, although the environment is also suitable for biological survival.

In 2000, scientists discovered a carbonate meteorite in Antarctica. Because the technology was not mature at that time, I thought there was a microfossil structure on it, but now it is only a naturally formed crystal.

It can be seen from the above that if Martian soil is brought back to the earth, there is no need to be afraid of microorganisms in Martian soil, not to mention the variation of microorganisms and the threat to human survival and safety.

But for safety reasons, the soil brought back from Mars will be isolated for several days before it can be released into the public environment. Because the environment of Mars in the solar system is most similar to that of the Earth, scientists have long designated Mars as the best choice for migrating planets, which is believed to be realized around 2030.

1964, American mariner 4 successfully circled Mars, marking the beginning of human exploration of Mars. Since then, man has sent more than 50 missions to Mars. Although only about half of the people succeeded, we already know that Mars is a cold planet covered with rubble, with a very thin atmosphere and water at the poles. There may have been life in the past. Man made a preliminary chemical analysis of the rocks and soil on the surface of Mars by using the Curiosity Rover. However, it would be more ideal to bring Martian soil samples back to Earth for close observation, so that scientists can conduct a more detailed investigation on the soil on Mars and study its chemical composition and possible organic compounds. These results can be verified in other laboratories, and with the improvement of sampling technology, they can continue to test the soil many times.

In fact, NASA and ESA are already planning such a project to bring Martian soil back to Earth, which will provide a key leap for us to understand the prospect of Martian soil chemistry and habitability. Needless to say, this will be a technically complicated task, including launching three different rockets from the earth, with many potential failure points from beginning to end. Many details of the plan are still in the design stage. The most optimistic assumption is the return date after 2030, but the project will include three main stages.

The first phase will include the Mars probe to be launched by NASA in 2020. The detector has the ability to collect soil samples, which will be packaged in sealed pipes and cached by subsequent landers for future recovery. In addition, ESA's ExoMars rover (scheduled to land on Mars in 20021year) will go deep into the surface of Mars to collect samples.

In the second stage, the second small rover will collect samples and send them to the Mars Ascending Launch Vehicle. The Mars Ascending Launch Vehicle is a small rocket that launches a soil sample container into the orbit of Mars. This container containing soil samples will fly around Mars until the third and final stage of the mission.

In the third stage, a spacecraft, such as Orion spacecraft, will be launched from the Earth to Mars, where it will meet the soil container, capture the container and then bring it back to the Earth. Once it reaches the earth, the spacecraft will enter the atmosphere and land somewhere in the United States. This soil container will be recycled, isolated and finally analyzed by an international team of scientists.

The return of Mars samples will bring some unique challenges, but scientists are already considering how to deal with Mars samples returning to Earth. For example, Mars, along with Europa and Enceladus, is designated as a V-class restricted return to Earth under planetary protection, which is a term reserved by NASA for cosmic objects that are considered important for chemical evolution or the origin of life.

With regard to the rocks and soils of Mars, it is necessary to analyze the unsterilized samples collected and brought back to Earth in time by using specific techniques under strict control. If any signs of non-earth-replicating entities are found, the returned samples must be sealed and preserved unless effective disinfection treatment is carried out. Before any Mars sample is released to the general scientific community for research, it is necessary to prepare a biological hazard and life test report before the sample is released to prove that the sample will not cause harm to the earth's biosphere.

I'm not afraid of anything. This is just a technical problem. Meteorites and other events that hit the earth happen every day, but there are no other world disasters except some large celestial bodies that cause "physical damage". There is nothing special about Martian soil.

It is unnecessary that "Martian soil" will bring disaster, and human technology can completely eliminate the fear of disaster. Bringing back soil from Mars refers to the Apollo program that the United States brought back soil from the moon. The properties of the surface soil of the moon are very different from those of the earth. The components include some glass balls or fragments, plagioclase, clinopyroxene, ilmenite, olivine, meteorite pyrite and natural iron fragments. When it floats in the air, it will cause symptoms like colds or allergies. In addition, some components may directly damage cells, but that's all. If there is no disturbance, Martian dust is like cement. Although it is very delicate, it will not climb into the human respiratory tract or digestive tract by itself, and it will not cause much harm to the human body. The soil on Mars is similar. Although humans have not collected Martian soil samples and returned to Earth, Mars has been hit by asteroids in history, and a few Martian rocks have been knocked out of the orbit of Mars and gradually attracted by the Earth. So far, scientists have found several pieces, but they have not caused disaster.

In terms of composition, Martian soil is different from earth soil because of its unique environment. There are many components such as iron oxide, but the inorganic components of Martian soil are basically found on the earth, and the organic components are basically found on the earth. There is no evidence that there is life on Mars. Even if there are species on Mars that pose a great threat to human beings or life on earth, human beings will not rashly extract Martian materials. In the future, after the Martian soil is obtained and returned to Earth, people will be allowed to directly contact it after strict procedures are confirmed to be harmless. Even if the physical damage is radioactive, a little Martian soil is basically harmless because of the purity of the material. Moreover, human beings have a perfect medical system. Even if the Martian soil contains organisms that pose a strong threat to human beings, it will only be confined to a certain range and it is difficult to cause global disasters. Moreover, the modern American landing exploration on Mars has made people know the soil characteristics of some areas on the surface of Mars, and no living things have been found, only some organic matter and substances (water/atmosphere, etc.). ) substances beneficial to life have been found.

Mars is a close neighbor of the earth. Atmospheric environment, distance from the earth and other factors make it the most suitable planet for human exploration and the most livable planet in the future. There will definitely be landings on Mars in the future, bringing back Martian soil. At that time, people will be proud and happy because of the successful landing on Mars, and there will be no global disaster caused by Martian soil. Unless the future changes in the orbit of Mars intersect with the orbit of the Earth, Mars and the Earth will collide at some point, which will cause almost all living things in the world to be burned by the high temperature generated by the collision.