Astronauts take at least 360 days to and from Mars at a time, how to ensure their safety?
According to the plans of the three major space powers of China, the United States and Russia, astronauts will certainly be sent to Mars within this century. Mars is about 55 million kilometers from Earth and more than 400 million kilometers from its farthest distance. Such a long distance poses a challenge to aerospace technology. Because according to nasa's requirements, it takes at least 180 days to launch a manned spacecraft to the surface of Mars. Some experts believe that it will take about 250 days. In contrast to this long journey, it takes only 3 days for a spacecraft on Earth to reach the moon. That is, even if calculated according to the fastest time, the time to Mars is 60 times that of the moon.
Heavy rockets
In order to set foot on Mars, the astronauts ate and drank in a spacecraft that was not very large for at least 180 days. The harm of the space environment to the human body has been studied since the 1950s and 1960s, and some conclusions have been reached. The United States and Russia have pioneered some medical research demonstrating the physical impairment of astronauts when faced with weightless environments in space. The main ones are:
1, bone loss, reduction of bone density; 2, muscle atrophy; 3, decline in fertility; 4, decline in immunity; permanent damage to vision (male astronauts will have long-term deformation of the eyeballs, need to wear reading glasses to see things clearly, the situation of women is better, the physiological reasons for this difference between men and women are not yet clear); 5, adverse reactions to psychological states, such as depression, etc.; 6, genetic changes. For example, American astronaut Scott. Kelly, who had been on the International Space Station for a year, returned to Earth when doctors examined his body and found that 7% of his genes had changed permanently, but unfortunately mainly tended to be negative.
Scott. Kelly
Think about it, it takes at least 180 days to get to Mars, and it takes another 180 days to return, which adds up to 360 days or a whole year. Has been confirmed by Scott. Kelly's one-year life in the microgravity environment of space has undergone genetic changes, and astronauts who theoretically carry out a mission to Mars will probably have this negative health situation.
In order to overcome these unfavorable factors, the U.S. and Russian national space departments are actively studying. For example, within NASA, a medical team of internists, psychologists, and psychiatrists was formed.
In addition to the above disadvantages, astronauts also face a very intuitive difficulty, that is, how to resist high-energy radiation from the depths of the Milky Way. Historically, human beings have completely escaped the protection of the Earth's magnetic field and have had few opportunities to be directly in the outer space environment, and only once. That was during the American Apollo mission. At that time, because the speed of spacecraft was not as fast as it is today, astronauts were exposed to deep space radiation for almost 12 days. Fortunately, the astronauts were physically examined and did not show much health damage.
American astronauts flew the Apollo mission
Whether it is the International Space Station or our country's space station, it is actually protected by the Earth's magnetic field. The magnetic field that surrounds the Earth, whose range extends outward for about 58,000 kilometers, is called the Van Allen Radiation Belt. The Van Allen radiation belt refers to the high-energy particle radiation belt that surrounds the Earth in the near-layer space near the Earth, and is mainly composed of electrons up to several megaelectronvolts captured in the geomagnetic field and protons up to several hundred megaelectron volts. The Van Allen radiation belt is divided into two layers, and there is a Fan Allen band gap between the inner and outer layers, and there is very little radiation in the seam. This Van Allen radiation belt, which wraps the Earth tightly in the middle. The space station is generally hundreds of kilometers above the earth's surface, completely protected by the Van Allen radiation belt.
Van Allen radiation belt
If astronauts set off for Mars, not counting the time spent on the surface of Mars, it will take at least a whole year just to go back and forth on the road. During this journey, the astronauts were not protected by the Van Allen radiation belt.
So, what radiation in the universe poses a threat to astronauts' bodies? There are two kinds of radiation in space. One is radiation from the sun. One is radiation from outside the solar system, that is, radiation from the depths of the Milky Way. Radiation from the sun alone poses a great threat to humanity. Solar radiation shows a cyclical change, every 11 years a cycle cycle, the outbreak of the "solar storm" is mainly released through enhanced electromagnetic radiation, high-energy charged particle streams and plasma clouds and other three forms of release, due to the protection of the Van Allen radiation belt, astronauts are equivalent to withstand hundreds of times higher radiation on the ground.
But radiation from deep within the Milky Way is even more dangerous, far more threatening than the sun. Astronomers call these rays from outside the solar system galactic cosmic rays. Deep in the Milky Way, including the galactic region near the galactic center, there are many hot clusters produced by massive stars. For example, the base of The Ship, one of the southern celestial constellations 20,000 light-years away from Earth, is considered by astronomers to be a strong source of cosmic radiation. There are many bright stars in the constellation of The Ship, and the brightest star is the "Old Man Star". Westerners call it Canopus, which means "ship navigator of King Menareas of Sparta". Since the star is relatively bright, it means that its energy is relatively high. These rays carry more energy, and some of them can easily penetrate the Earth's magnetic field, causing irreversible damage to human cellular tissue. For example, it may cause cancer, cardiovascular disease, musculoskeletal and nervous system damage, etc. According to NASA research data, the radiation dose of astronauts on a round trip to Mars is about 15 to 20 times that of the radiation dose allowed by nuclear power plant or nuclear submarine staff. The staff on the nuclear submarine, their chance of cancer is 3% higher than the average person. If they are 15 to 20 times more exposed to radiation, the harm to the human body can be imagined.
Ship base nebula
If you want to complete the Mars mission smoothly and safely, you must find ways to take certain measures to resist these strong radiation from stars and ensure the health of astronauts. So, what are the relevant protection technology solutions we have at present, or what may be implemented in the future? I'll talk about that in the next article.
Author: Skeptical Explorer