Such a concept as solar radiation has become known quite a long time ago. As numerous studies have shown, it is not always responsible for increasing the level of air ionization.
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Cosmic radiation: truth or myth?
Cosmic rays are radiation produced by explosions supernova, and also as a consequence of thermonuclear reactions in the Sun. Different nature the origin of the rays also affects their basic characteristics. Cosmic rays that penetrate from space beyond our solar system can be conditionally divided into two types - galactic and intergalactic. The latter species remains the least studied, since the concentration of primary radiation in it is minimal. That is, intergalactic radiation is not of particular importance, since it is completely neutralized in our atmosphere.
Unfortunately, little can be said about the rays that come to us from our galaxy called the Milky Way. Despite the fact that its size exceeds 10,000 light years, any changes in the radiation field at one end of the galaxy will immediately reverberate at the other.
The dangers of radiation from space
Direct cosmic radiation is destructive to a living organism, so its influence is extremely dangerous for humans. Fortunately, our Earth is reliably protected from these space aliens by a dense dome of the atmosphere. It serves as an excellent protection for all life on earth, as it neutralizes direct cosmic radiation. But not completely. When it collides with air, it breaks down into smaller particles. ionizing radiation, each of which enters into an individual reaction with its atoms. Thus, high-energy radiation from space is weakened and forms secondary radiation. At the same time, it loses its lethality - the level of radiation becomes approximately the same as in X-rays. But don’t be alarmed—this radiation completely disappears as it passes through the Earth’s atmosphere. Whatever the sources cosmic rays, and no matter how powerful they are, the danger to a person who is on the surface of our planet is minimal. It can only cause tangible harm to astronauts. They are exposed to direct cosmic radiation, since they do not have natural protection in the form of an atmosphere.
The energy released by cosmic rays primarily affects the Earth's magnetic field. Charged ionizing particles literally bombard it and become the cause of the most beautiful atmospheric phenomenon - . But that is not all - radioactive particles, due to their nature, can cause malfunctions in various electronics. And if in the last century this did not cause much discomfort, in our time it is a very serious problem, since the most important aspects of modern life are tied to electricity.
Humans are also susceptible to these visitors from space, although the mechanism of action of cosmic rays is very specific. Ionized particles (that is, secondary radiation) affect the Earth's magnetic field, thereby causing storms in the atmosphere. Everyone knows that the human body consists of water, which is very susceptible to magnetic vibrations. Thus, cosmic radiation affects the cardiovascular system and causes poor health in weather-sensitive people. This is, of course, unpleasant, but by no means fatal.
What protects the Earth from solar radiation?
The Sun is a star, in the depths of which various thermonuclear reactions constantly take place, which are accompanied by strong energy emissions. These charged particles are called solar wind and have a strong influence on our Earth, or rather on its magnetic field. It is with it that ionized particles interact, which form the basis of the solar wind.
According to the latest research scientists from all over the world, the plasma shell of our planet plays a special role in neutralizing the solar wind. This happens in the following way: solar radiation collides with the Earth's magnetic field and dissipates. When there is too much of it, the plasma shell takes the blow, and an interaction process similar to a short circuit occurs. The consequence of such a struggle may be cracks in the protective shield. But nature has provided for this too - streams of cold plasma rise from the surface of the Earth and rush to places with weakened protection. Thus, the magnetic field of our planet reflects the impact from space.
But it is worth stating the fact that solar radiation, unlike cosmic radiation, still reaches the Earth. At the same time, you should not worry in vain, because in essence this is the energy of the Sun, which should fall on the surface of our planet in a dispersed state. Thus, it heats the Earth's surface and helps develop life on it. Thus, it is worth clearly distinguishing between different types of radiation, because some of them not only have no negative impact, but also necessary for the normal functioning of living organisms.
However, not all substances on Earth are equally susceptible to solar radiation. There are surfaces that absorb it more than others. These are, as a rule, underlying surfaces with a minimum level of albedo (the ability to reflect solar radiation) - earth, forest, sand.
Thus, the temperature on the Earth’s surface, as well as the length of daylight hours, directly depends on how much solar radiation is absorbed by the atmosphere. I would like to say that the bulk of energy still reaches the surface of our planet, because air envelope The Earth serves as a barrier only for rays of the infrared spectrum. But UV rays are only partially neutralized, which leads to some skin problems in humans and animals.
The influence of solar radiation on the human body
When exposed to rays of the infrared spectrum of solar radiation, a thermal effect clearly manifests itself. It promotes vasodilation, stimulates the cardiovascular system, and activates skin respiration. As a result, the main systems of the body relax, and the production of endorphins (hormones of happiness), which have an analgesic and anti-inflammatory effect, increases. Heat also affects metabolic processes, activating metabolism.
Light radiation from solar radiation has a significant photochemical effect, which activates important processes in tissues. This type of solar radiation allows a person to use one of the most important systems touch of the external world - vision. It is these quanta that we should be grateful for the fact that we see everything in color.
Important influencing factors
Solar radiation in the infrared spectrum also stimulates brain activity and is responsible for human mental health. It is also important that this type of solar energy affects our biological rhythms, that is, into phases active work and sleep.
Without light particles, many vital processes would be at risk, which could lead to the development of various diseases, including insomnia and depression. Also, with minimal contact with solar light radiation, a person’s ability to work is significantly reduced, and most processes in the body slow down.
UV radiation is quite useful for our body, since it also triggers immunological processes, that is, it stimulates the body's defenses. It is also needed for the production of porphyrite, an analogue of plant chlorophyll in our skin. However, excess UV rays can cause burns, so it is very important to know how to properly protect yourself from this during peak periods. solar activity.
As you can see, the benefits of solar radiation for our body are undeniable. Many people are very worried about whether food absorbs this type of radiation and whether it is dangerous to eat contaminated foods. I repeat - solar energy has nothing to do with cosmic or atomic radiation, which means there is no need to be afraid of it. And it would be pointless to avoid it... No one has yet looked for a way to escape from the Sun.
The text presented below should be regarded as the personal opinion of the author. He does not have any secret information (or access to it). Everything that is presented is facts from open sources plus a little common sense (“couch analytics”, if you like).
Science fiction - all those blasters and pew-pews in outer space in tiny single-seat fighters - has taught humanity to seriously overestimate the benevolence of the Universe towards warm protein organisms. This is especially evident when science fiction writers describe travel to other planets. Alas, the exploration of “real space” instead of the usual several hundred “kames” is protected magnetic field Land will be a more difficult undertaking than the average person imagined just a decade ago.
So here's my main point. Psychological climate and conflicts within the crew are far from the main problems that humans will face when organizing manned flights to Mars.
The main problem of a person traveling beyond the Earth's magnetosphere- a problem with capital letters"R".
What is cosmic radiation and why we don’t die from it on Earth
Ionizing radiation in space (beyond the few hundred kilometers of near-Earth space that humans have actually mastered) consists of two parts.
Radiation from the Sun. This is, first of all, the “solar wind” - a stream of particles that constantly “blows” in all directions from the star and which is extremely good for future space sailing ships, because it will allow them to properly accelerate for travel beyond the solar system. But for living beings, the main part of this wind is not particularly useful. It is wonderful that we are protected from hard radiation by a thick layer of the atmosphere, the ionosphere (the one where ozone holes), and also the powerful magnetic field of the Earth.
In addition to the wind, which scatters more or less evenly, our star also periodically shoots so-called solar flares. The latter are ejections of coronal matter from the Sun. They are so serious that from time to time they lead to problems for people and technology even on Earth, where the most fun, I repeat, is well screened.
So, we have the atmosphere and magnetic field of the planet. It's already enough close space, at a distance of ten or two thousand kilometers from the Earth, a solar flare (even a weak one, just a couple of Hiroshimas), hitting the ship, is guaranteed to disable its living contents without the slightest chance of survival. We have absolutely nothing to prevent this today - at the current level of development of technologies and materials. For this and only for this reason, humanity will have to postpone the months-long journey to Mars until we solve this problem at least partially. You will also have to plan it during periods of calmest sun and pray a lot to all the technical gods.
Cosmic rays. These ubiquitous villainous things carry a huge amount of energy (more than the LHC can pump into a particle). They come from other parts of our galaxy. Getting into the shield of the earth’s atmosphere, such a beam interacts with its atoms and breaks down into dozens of less energetic particles, which cascade into streams of even less energetic (but also dangerous) ones, and as a result, all this splendor is shed as radiation rain on the surface of the planet. Approximately 15% of background radiation on Earth comes from visitors from space. The higher you live above sea level, the higher the dose you catch during your life. And this happens around the clock.
As school exercise try to imagine what will happen to a spaceship and its “living contents” if they are directly hit by such a beam somewhere in outer space. Let me remind you that the flight to Mars will take several months, a hefty ship will have to be built for this, and the likelihood of the “contact” described above (or even more than one) is quite high. Unfortunately, it is simply impossible to ignore it during long flights with a live crew.
What else?
In addition to the radiation that reaches the Earth from the Sun, there is also solar radiation that the planet’s magnetosphere repels, does not allow in, and, most importantly, accumulates*. Meet the readers. This is the Earth's radiation belt (ERB). It is also known as the Van Allen belt, as it is called abroad. The astronauts will have to overcome it, as they say, “at full speed”, so as not to receive a lethal dose of radiation in just a few hours. Repeated contact with this belt - if we are contrary common sense we decide to return the astronauts from Mars to Earth - it could easily finish them off.
*A significant proportion of Van Allen belt particles acquire dangerous speeds already in the belt itself. That is, it not only protects us from radiation from the outside, but also enhances this accumulated radiation.
So far we have been talking about outer space. But we must not forget that Mars (unlike Earth) has almost no magnetic field**, and the atmosphere is thin and thin, so being exposed to these negative factors people will not only be in flight.
**Okay, there's a little- near the south pole.
Hence the conclusion. Future colonists will most likely live not on the surface of the planet (as we were shown in the epic movie “Mission to Mars”), but deep down. underneath it.
What should I do?
First of all, apparently, do not harbor illusions that all these problems will be resolved quickly (within a dozen or two or three years). To avoid the death of the crew from radiation sickness, we will either have to not send them there at all and explore space with the help of smart machines (by the way, not the stupidest decision), or we will have to work very hard, because if I am right, then sending people to Mars with creating a permanent colony there is a completely impossible task for one country (even the USA, even Russia, even China) in the next half century, or even longer. One ship for such a mission will cost an amount equivalent to the construction and full maintenance of a couple of ISS (see below).
And yes, I forgot to say: the pioneers of Mars will obviously be “suicide bombers”, since there is no way back, no long and comfortable life on Mars, we will most likely be able to provide them with them in the next half century.
What could a mission to Mars theoretically look like if we had all the resources and technologies of old Earth? Compare what is described below with what you saw in cult film"Martian".
Mission to Mars. Conditionally realistic version
Firstly, humanity will have to work hard and build a cyclopean-sized spaceship with powerful anti-radiation protection, which can partially compensate for the hellish radiation load on the crew outside the Earth’s magnetic field and ensure the delivery of more or less living colonists to Mars - one way.
What might such a ship look like?
This is a hefty colossus tens (or better yet hundreds) of meters in diameter, provided with its own magnetic field (superconducting electromagnets) and energy sources to maintain it (nuclear reactors). The huge dimensions of the structure make it possible to fill it from the inside with radiation-absorbing materials (for example, it can be leaded foam plastic or sealed containers with simple or “heavy” water), which will have to be transported into orbit for decades (!) and mounted around a relatively tiny life support capsule, where then we will place the astronauts.
In addition to its size and high cost, the Martian ship must be damn reliable and, most importantly, completely autonomous in terms of control. To deliver the crew alive, the safest thing to do would be to put them in an artificial coma and cool them a little (just a couple of degrees) to slow down metabolic processes. In this state, people a) will be less sensitive to radiation, b) take up less space and are cheaper to shield from the same radiation.
Obviously, in addition to the ship, we need artificial intelligence that can confidently deliver the ship into Mars orbit, unload the colonists onto its surface without damaging either itself or the cargo in the process, and then, without the participation of people, return the astronauts to consciousness (already on Mars). We don’t have such technologies yet, but there is some hope that such AI, and most importantly the political and economic resources for building the described ship, will appear in our country, say, closer to the middle of the century.
The good news is that the Martian “ferry” for colonists may well be reusable. He will have to travel like a shuttle between Earth and the final destination, delivering shipments of “living cargo” to the colony to replace people who have dropped out “from natural causes.” To deliver “non-living” cargo (food, water, air and equipment), radiation protection is not particularly needed, so it is not necessary to make a supership into a Martian truck. It is needed solely for the delivery of colonists and possibly plant seeds / young farm animals.
Secondly, it is necessary to send equipment and supplies of water, food and oxygen to Mars in advance for a crew of 6-12 people for 12-15 years (taking into account all force majeure). This in itself is a non-trivial problem, but let’s assume that we are not limited in resources to solve it. Suppose that the wars and political disturbances of the Earth have subsided, and Mars mission The whole planet works in unison.
The equipment being thrown to Mars, as you should have guessed, is a fully autonomous robot with artificial intelligence and powered by compact nuclear reactors. They will have to methodically, over the course of ten to one and a half years, first dig a deep tunnel under the surface of the red planet. Then - in a few more years - a small network of tunnels, into which life support units and supplies for a future expedition will have to be dragged, and then all this will be hermetically assembled into an autonomous sub-Martian village.
A metro-like dwelling seems to be the optimal solution for two reasons. Firstly, it shields astronauts from cosmic rays already on Mars itself. Secondly, due to the residual “marsothermal” activity of the subsurface of the planet, it is a degree or two warmer than outside. This will be useful to the colonists both for saving energy and for growing potatoes on their own feces.
Let us clarify an important point: the colony will have to be built in the southern hemisphere, where there is still a residual magnetic field on the planet.
Ideally, astronauts will not have to go to the surface at all (they will either not see Mars “live” at all, or they will see it once - during landing). All the work on the surface will have to be done by robots, whose actions the colonists will have to direct from their bunker throughout their short lives (twenty years under a fortunate combination of circumstances).
Third, we need to talk about the crew itself and the methods for selecting it.
The ideal scheme for the latter would be to search the entire Earth for... genetically identical (monozygotic) twins, one of whom has just turned into an organ donor (for example, having “luckily” been in a car accident). It sounds extremely cynical, but don’t let that stop you from reading the text to the end.
What does a donor twin give us?
A dead twin gives his brother (or sister) the opportunity to become an ideal colonist on Mars. The fact is that the red bone marrow of the first, being delivered to the red planet in a container additionally protected from radiation, can be transfused into the astronaut twin. This increases the chances of his survival from radiation sickness, acute leukemia and other troubles that are very likely to happen to the colonist during the years of the mission.
So, what does the screening process for future colonists look like?
We select several million twins. We wait until something happens to one of them and make an offer to the remaining one. A pool of, say, one hundred thousand potential candidates is recruited. Now, within this pool, we conduct a final selection for psychological compatibility and professional suitability.
Naturally, to expand the sample, astronauts will have to be selected throughout the Earth, and not in one or two countries.
Of course, some technology for identifying candidates that are particularly resistant to radiation would be a great help. It is known that some people are much more resistant to radiation than others. Surely it can be identified using certain genetic markers. If we complement the idea with twins with this method, together they should significantly increase the survival rate of Martian colonists.
In addition, it would be useful to learn how to transfuse bone marrow to people in zero gravity. This is not the only thing that needs to be invented specifically for this project, but, fortunately, we still have time, and the ISS is still hanging out in Earth orbit as if specifically for testing such technologies.
PS. I must specifically make a reservation that I am not a principled opponent of space travel and believe that sooner or later “space will be ours.” The only question is the price of this success, as well as the time that humanity will spend to develop necessary technologies. I think under the influence science fiction And popular culture Many of us are quite careless in terms of understanding the difficulties that must be overcome along the way. To make this part a little more sobering« cosmo-optimists» and this text was written.
In parts I will tell you what other options we have regarding human space exploration in the long term.
Orbit International space station It was raised several times, and now its height is more than 400 km. This was done in order to take the flying laboratory away from the dense layers of the atmosphere, where gas molecules still quite noticeably slow down the flight and the station loses altitude. In order not to adjust the orbit too often, it would be nice to raise the station even higher, but this cannot be done. The lower (proton) radiation belt begins approximately 500 km from Earth. A long flight inside any of the radiation belts (and there are two of them) will be disastrous for the crews.
Cosmonaut-liquidator
Nevertheless, it cannot be said that at the altitude at which the ISS currently flies, there are no radiation safety problems. Firstly, in the South Atlantic region there is the so-called Brazilian, or South Atlantic, magnetic anomaly. Here the Earth’s magnetic field seems to sags, and with it the lower radiation belt appears closer to the surface. And the ISS still touches it, flying in this area.
Secondly, a person in space is threatened by galactic radiation - a stream of charged particles rushing from all directions and at enormous speed, generated by supernova explosions or the activity of pulsars, quasars and other anomalous stellar bodies. Some of these particles are retained by the Earth's magnetic field (which is one of the factors in the formation of radiation belts), while the other part loses energy in collisions with gas molecules in the atmosphere. Something reaches the surface of the Earth, so that a small radioactive background is present absolutely everywhere on our planet. On average, a person living on Earth who does not deal with sources of radiation receives a dose of 1 millisievert (mSv) annually. An astronaut on the ISS earns 0.5−0.7 mSv. Daily!
The Earth's radiation belts are regions of the magnetosphere in which high-energy charged particles accumulate. The inner belt consists mainly of protons, the outer one of electrons. In 2012, another belt was discovered by a NASA satellite, which is located between the two known ones.
“An interesting comparison can be made,” says Vyacheslav Shurshakov, head of the department of radiation safety of cosmonauts at the Institute of Medical and Biological Problems of the Russian Academy of Sciences, candidate of physical and mathematical sciences. — The permissible annual dose for a nuclear power plant employee is considered to be 20 mSv, which is 20 times more than what an ordinary person receives. For emergency response specialists, these specially trained people, the maximum annual dose is 200 mSv. This is already 200 times more compared to the usual dose and... almost the same as what an astronaut receives after working for a year on the ISS.”
Currently, medicine has established a maximum dose limit that cannot be exceeded during a person’s life in order to avoid serious problems with health. This is 1000 mSv, or 1 Sv. Thus, even a nuclear power plant worker with his standards can work quietly for fifty years without worrying about anything. The astronaut will exhaust his limit in just five years. But, even after flying for four years and gaining his legal 800 mSv, he is unlikely to be allowed on a new flight of one year duration, because there will be a threat of exceeding the limit.
“Another factor of radiation danger in space,” explains Vyacheslav Shurshakov, “is the activity of the Sun, especially the so-called proton emissions. At the moment of ejection a short time an astronaut on the ISS can receive up to an additional 30 mSv. It’s good that solar proton events occur rarely - 1-2 times during the 11-year cycle of solar activity. The bad thing is that these processes occur stochastically, in a random order, and are difficult to predict. I don’t remember such a thing that we would have been warned in advance by our science about the impending release. Usually things are different. Dosimeters on the ISS suddenly show an increase in the background, we call solar specialists and receive confirmation: yes, anomalous activity of our star is observed. It is precisely because of such sudden solar proton events that we never know exactly what dose an astronaut will bring with him from a flight.”
Particles that drive you crazy
Radiation problems for crews going to Mars will begin on Earth. A ship weighing 100 tons or more will have to accelerate for a long time in low-Earth orbit, and part of this trajectory will pass inside the radiation belts. These are no longer hours, but days and weeks. Next - exit beyond the magnetosphere and galactic radiation in its primordial form, many heavy charged particles, the impact of which is little felt under the “umbrella” of the Earth’s magnetic field.
“The problem is,” says Vyacheslav Shurshakov, “that the effect of particles on critical organs of the human body (for example, the nervous system) has been little studied today. Perhaps radiation will cause memory loss in the astronaut, cause abnormal behavioral reactions, and aggression. And it is very likely that these effects will not be tied to a specific dose. Until enough data has been accumulated on the existence of living organisms outside the Earth’s magnetic field, going on long-term space expeditions is very risky.”
When radiation safety specialists suggest to designers spacecraft strengthen biosecurity, they respond with a seemingly completely rational question: “What’s the problem? Did any of the astronauts die from radiation sickness?” Unfortunately, the radiation doses received on board not even the starships of the future, but the familiar ISS, although they fit into the standards, are not at all harmless. For some reason, Soviet cosmonauts never complained about their eyesight - apparently, they were afraid for their careers, but American data clearly show that space radiation increases the risk of cataracts, clouding of the lens. Blood studies of astronauts demonstrate an increase in chromosomal aberrations in lymphocytes after each space flight, which in medicine is considered a tumor marker. In general, it was concluded that receiving a permissible dose of 1 Sv during a lifetime shortens life on average by three years.
Moon risks
One of the “strong” arguments of supporters of the “lunar conspiracy” is the assertion that crossing the radiation belts and being on the Moon, where there is no magnetic field, would cause the inevitable death of astronauts from radiation sickness. American astronauts we actually had to cross the Earth’s radiation belts—proton and electron. But this happened over just a few hours, and the doses received by the Apollo crews during the missions turned out to be significant, but comparable to those received by long-time ISS residents. “Of course, the Americans were lucky,” says Vyacheslav Shurshakov, “because not a single solar proton event occurred during their flights. If this had happened, the astronauts would have received sublethal doses—not 30 mSv, but 3 Sv.
Wet your towels!
“We, experts in the field of radiation safety,” says Vyacheslav Shurshakov, “insist that the protection of crews be strengthened. For example, on the ISS the most vulnerable are the astronauts' cabins, where they rest. There is no additional mass, and only a metal wall a few millimeters thick separates a person from outer space. If we reduce this barrier to the water equivalent accepted in radiology, it is only 1 cm of water. For comparison: the earth's atmosphere, under which we shelter from radiation, is equivalent to 10 m of water. We recently proposed protecting astronaut cabins with an additional layer of water-soaked towels and napkins, which would greatly reduce the effects of radiation. Medicines are being developed to protect against radiation, although they are not yet used on the ISS. Perhaps in the future, using medical methods and genetic engineering we will be able to improve the human body so that its critical organs are more resistant to radiation factors. But in any case, without close scientific attention to this problem of distant space flights You can forget."
Tambov regional state educational institution
General education boarding school with initial flight training
named after M. M. Raskova
Essay
"Cosmic Radiation"
Completed by: student of 103 platoon
Krasnoslobodtsev Alexey
Head: Pelivan V.S.
Tambov 2008
1. Introduction.
2. What is cosmic radiation.
3. How cosmic radiation arises.
4. Impact of cosmic radiation on humans and the environment.
5. Means of protection against cosmic radiation.
6. Formation of the Universe.
7. Conclusion.
8. Bibliography.
1. INTRODUCTION
Man will not remain on earth forever,
but in pursuit of light and space,
at first it will timidly penetrate beyond
atmosphere, and then conquer everything
circumglobal space.
K. Tsiolkovsky
The 21st century is the century of nanotechnology and gigantic speeds. Our life flows incessantly and inevitably, and each of us strives to keep up with the times. Problems, problems, searches for solutions, a huge flow of information from all sides... How to cope with all this, how to find your place in life?
Let's try to stop and think...
Psychologists say that a person can look at three things indefinitely: fire, water and the starry sky. Indeed, the sky has always attracted man. It is amazingly beautiful at sunrise and sunset, it seems endlessly blue and deep during the day. And, looking at the weightless clouds flying by, watching the flight of birds, you want to break away from the everyday bustle, rise into the sky and feel the freedom of flight. And the starry sky on a dark night... how mysterious and inexplicably beautiful it is! And how I want to lift the veil of mystery. At such moments, you feel like a small particle of a huge, frightening and yet irresistibly beckoning space, which is called the Universe.
What is the Universe? How did it come about? What does it conceal within itself, what has it prepared for us: a “universal mind” and answers to numerous questions or the death of humanity?
Questions arise in an endless stream.
Space... For ordinary person he seems unattainable. But, nevertheless, its impact on a person is constant. By and large, it was outer space that provided the conditions on Earth that led to the emergence of life as we are accustomed to, and hence the emergence of man himself. The influence of space is still felt to a large extent today. “Particles of the universe” reach us through protective layer atmosphere and have an impact on a person’s well-being, his health, and the processes that occur in his body. This is for us living on earth, but what can we say about those who explore outer space.
I was interested in this question: what is cosmic radiation and what is its effect on humans?
I am studying at a boarding school with initial flight training. Boys come to us who dream of conquering the sky. And they have already taken the first step towards realizing their dream, leaving the walls of their home and deciding to come to this school, where they study the basics of flight, the design of aircraft, where they have the opportunity every day to communicate with people who have repeatedly taken to the skies. And even if these are only planes for now, which cannot fully overcome gravity. But this is only the first step. The fate and life path of any person begins with a small, timid, uncertain step of a child. Who knows, maybe one of them will take the second step, the third... and will master space aircrafts and will rise to the stars into the boundless expanses of the Universe.
Therefore, this issue is quite relevant and interesting for us.
2. WHAT IS COSMIC RADIATION?
The existence of cosmic rays was discovered at the beginning of the twentieth century. In 1912, the Australian physicist W. Hess, while ascending in a balloon, noticed that the discharge of an electroscope at high altitudes occurs much faster than at sea level. It became clear that the ionization of air, which removed the discharge from the electroscope, has extraterrestrial origin. Millikan was the first to make this assumption, and it was he who gave this phenomenon its modern name - cosmic radiation.
It has now been established that primary cosmic radiation consists of stable particles high energies, flying in the most various directions. The intensity of cosmic radiation in the solar system region averages 2-4 particles per 1 cm 2 per 1 s. It consists of:
- protons – 91%
- α-particles – 6.6%
- nuclei of other heavier elements – less than 1%
- electrons – 1.5%
- X-rays and gamma rays of cosmic origin
- solar radiation.
Primary comic particles flying from outer space interact with atomic nuclei upper layers atmosphere and form so-called secondary cosmic rays. Cosmic ray intensity near magnetic poles The Earth is approximately 1.5 times larger than at the equator.
The average energy of cosmic particles is about 10 4 MeV, and the energy of individual particles is 10 12 MeV and more.
3. HOW DOES COSMIC RADIATION ARISE?
According to modern concepts, the main source of high-energy cosmic radiation is supernova explosions. According to data obtained using NASA's orbital X-ray telescope, new evidence has been obtained that a significant amount of cosmic radiation constantly bombarding the Earth is produced by the shock wave propagating from a supernova explosion, which was recorded back in 1572. Based on observations from the Chandra X-ray Observatory, the remnants of the supernova continue to accelerate at speeds of more than 10 million km/h, producing two shock waves accompanied by a massive release x-ray radiation. Moreover, one wave
moves outward into the interstellar gas, and the second
inwards, towards the center former star. You can also
argue that a significant proportion of energy
"internal" shock wave goes to accelerate atomic nuclei to speeds close to light.
High energy particles come to us from other Galaxies. They can achieve such energies by accelerating in the inhomogeneous magnetic fields of the Universe.
Naturally, the source of cosmic radiation is also the star closest to us - the Sun. The Sun periodically (during flares) emits solar cosmic rays, which consist mainly of protons and α-particles with low energy.
4. IMPACT OF COSMIC RADIATION ON HUMANS
AND THE ENVIRONMENT
The results of a study conducted by researchers at the Sophia Antipolis University in Nice show that cosmic radiation played a critical role in the origin of biological life on the ground. It has long been known that amino acids can exist in two forms - left-handed and right-handed. However, on Earth, at the basis of all biological organisms, evolved naturally, only left-handed amino acids are found. According to university staff, the reason should be sought in space. So-called circularly polarized cosmic radiation destroyed right-handed amino acids. Circularly polarized light is a form of radiation polarized by cosmic electromagnetic fields. This radiation is produced when particles of interstellar dust line up along magnetic field lines that permeate the entire surrounding space. Circularly polarized light accounts for 17% of all cosmic radiation anywhere in space. Depending on the direction of polarization, such light selectively breaks down one of the types of amino acids, which is confirmed by experiment and the results of a study of two meteorites.
Cosmic radiation is one of the sources of ionizing radiation on Earth.
The natural radiation background due to cosmic radiation at sea level is 0.32 mSv per year (3.4 μR per hour). Cosmic radiation constitutes only 1/6 of the annual effective equivalent dose received by the population. Radiation levels are not the same for various areas. Thus, the North and South poles are more susceptible to cosmic rays than the equatorial zone, due to the presence of a magnetic field near the Earth that deflects charged particles. In addition, the higher you are from the earth's surface, the more intense the cosmic radiation. Thus, living in mountainous areas and constantly using air transport, we are exposed to an additional risk of radiation exposure. People living above 2000 m above sea level receive an effective equivalent dose from cosmic rays several times greater than those living at sea level. When ascending from a height of 4000 m ( maximum height residence of people) up to 12,000 m (the maximum flight altitude of passenger transport), the level of exposure increases by 25 times. And during a 7.5-hour flight on a conventional turboprop aircraft, the radiation dose received is approximately 50 μSv. In total, through the use of air transport, the Earth's population receives a radiation dose of about 10,000 man-Sv per year, which is an average per capita in the world of about 1 μSv per year, and in North America approximately 10 μSv.
Ionizing radiation negatively affects human health; it disrupts the vital functions of living organisms:
· having great penetrating ability, it destroys the most intensively dividing cells of the body: bone marrow, digestive tract, etc.
· causes changes at the gene level, which subsequently leads to mutations and the occurrence of hereditary diseases.
· causes intensive division of malignant tumor cells, which leads to the occurrence of cancer.
leads to changes in nervous system and the work of the heart.
· sexual function is inhibited.
· Causes visual impairment.
Radiation from space even affects the vision of airline pilots. The vision conditions of 445 men aged about 50 years were studied, of whom 79 were airline pilots. Statistics have shown that for professional pilots the risk of developing cataracts of the lens nucleus is three times higher than for representatives of other professions, and even more so for astronauts.
Cosmic radiation is one of the unfavorable factors for the body of astronauts, the importance of which is constantly increasing as the range and duration of flights increase. When a person finds himself outside the Earth's atmosphere, where the bombardment by galactic rays, as well as solar cosmic rays, is much stronger: about 5 thousand ions can rush through his body in a second, capable of destroying chemical bonds in the body and cause a cascade of secondary particles. The danger of radiation exposure to ionizing radiation in low doses is due to an increased risk of cancer and hereditary diseases. The greatest danger from intergalactic rays comes from heavy charged particles.
Based on biomedical research and the estimated levels of radiation existing in space, maximum permissible radiation doses for astronauts were determined. They are 980 rem for the feet, ankles and hands, 700 rem for the skin, 200 rem for the blood-forming organs and 200 rem for the eyes. The experimental results showed that in conditions of weightlessness the influence of radiation increases. If these data are confirmed, then the danger of cosmic radiation to humans is likely to be greater than originally thought.
Cosmic rays can influence the weather and climate of the Earth. British meteorologists have proven that cloudy weather is observed during periods of greatest cosmic ray activity. The fact is that when cosmic particles burst into the atmosphere, they generate wide “showers” of charged and neutral particles, which can provoke the growth of droplets in clouds and an increase in cloudiness.
According to research by the Institute of Solar-Terrestrial Physics, an anomalous surge in solar activity is currently observed, the causes of which are unknown. A solar flare is a release of energy comparable to the explosion of several thousand hydrogen bombs. During particularly strong outbreaks electromagnetic radiation When reaching the Earth, it changes the planet’s magnetic field - as if it shakes it, which affects the well-being of weather-sensitive people. These, according to the World Health Organization, constitute 15% of the planet's population. Also, with high solar activity, microflora begins to multiply more intensively and a person’s susceptibility to many infectious diseases increases. Thus, influenza epidemics begin 2.3 years before the maximum solar activity or 2.3 years after.
Thus, we see that even a small part of cosmic radiation that reaches us through the atmosphere can have a noticeable effect on the human body and health, on the processes occurring in the atmosphere. One of the hypotheses for the origin of life on Earth suggests that cosmic particles play a significant role in biological and chemical processes on our planet.
5. COSMIC RADIATION PROTECTION MEANS
Penetration Issues
man into space - a kind of trial
the stone of maturity of our science.
Academician N. Sissakyan.
Despite the fact that the radiation of the Universe may have led to the origin of life and the appearance of man, for man himself in pure form it is destructive.
Living space person is limited to very minor
distances - this is the Earth and several kilometers above its surface. And then – “hostile” space.
But, since man does not give up trying to penetrate the expanses of the Universe, but is mastering them more and more intensively, the need arose to create certain means of protection against negative influence space. This is of particular importance for astronauts.
Contrary to popular belief, it is not the Earth’s magnetic field that protects us from the attack of cosmic rays, but a thick layer of the atmosphere, where there is a kilogram of air for every cm 2 of surface. Therefore, upon flying into the atmosphere, a cosmic proton, on average, overcomes only 1/14 of its height. Astronauts are deprived of such a protective shell.
As calculations show, reduce risk radiation damage to zero during space flight is impossible. But you can minimize it. And here the most important thing is passive protection spaceship, i.e. its walls.
To reduce the risk of dose loads from solar cosmic rays, their thickness should be at least 3-4 cm for light alloys. Plastics could be an alternative to metals. For example, polyethylene, the same material from which ordinary shopping bags are made, blocks 20% more cosmic rays than aluminum. Reinforced polyethylene is 10 times stronger than aluminum and at the same time lighter than “winged metal”.
WITH protection from galactic cosmic rays, possessing gigantic energies, everything is much more complicated. Several ways to protect astronauts from them are proposed. You can create a layer of protective substance around the ship similar to the earth's atmosphere. For example, if you use water, which is necessary in any case, you will need a layer 5 m thick. In this case, the mass of the water reservoir will approach 500 tons, which is a lot. You can also use ethylene - solid, which does not require tanks. But even then the required mass would be at least 400 tons. Liquid hydrogen can be used. It blocks cosmic rays 2.5 times better than aluminum. True, fuel containers would be bulky and heavy.
Was suggested another scheme for protecting people in orbit, which can be called magnetic circuit. A charged particle moving across a magnetic field is acted upon by a force directed perpendicular to the direction of motion (Lorentz force). Depending on the configuration of the field lines, the particle can deviate in almost any direction or enter a circular orbit, where it will rotate indefinitely. To create such a field, magnets based on superconductivity will be required. Such a system will have a mass of 9 tons, it is much lighter than substance protection, but still heavy.
Proponents of another idea propose charging the spacecraft with electricity, if the voltage of the outer skin is 2 10 9 V, then the ship will be able to reflect all protons of cosmic rays with energies up to 2 GeV. But the electric field will extend to a distance of tens of thousands of kilometers, and the spacecraft will attract electrons from this huge volume. They will crash into the shell with an energy of 2 GeV and behave in the same way as cosmic rays.
“Clothing” for cosmonauts’ space walks outside the spacecraft should be a whole rescue system:
must create the necessary atmosphere for breathing and maintaining pressure;
· must ensure the removal of heat generated by the human body;
· it should protect against overheating if a person is on the sunny side, and against cooling if in the shade; the difference between them is more than 100 0 C;
· protect from blinding by solar radiation;
· protect from meteoric substances;
· must allow free movement.
Development of the space suit began in 1959. There are several modifications of spacesuits; they are constantly changing and improving, mainly through the use of new, more advanced materials.
Space suit- this is a complex and expensive device, and this is easy to understand if you familiarize yourself with the requirements presented, for example, to the spacesuit of the Apollo cosmonauts. This spacesuit must protect the astronaut from exposure to the following factors:
Structure of a semi-rigid spacesuit (for space)
The first spacesuit for going into open space, which A. Leonov used, was rigid, unyielding, weighing about 100 kg, but his contemporaries considered it a real miracle of technology and “a machine more complex than a car.”
Thus, all proposals to protect astronauts from cosmic rays are not reliable.
6. EDUCATION OF THE UNIVERSE
To be honest, we not only want to know
how it is structured, but also, if possible, to achieve the goal
utopian and daring in appearance - understand why
nature is just like that. This is
Promethean element of scientific creativity.
A. Einstein.
So, cosmic radiation comes to us from the boundless expanses of the Universe. How did the Universe itself form?
It was Einstein who came up with the theorem on the basis of which the hypotheses of its occurrence were put forward. There are several hypotheses for the formation of the Universe. In modern cosmology, the two most popular are the Big Bang theory and the inflationary theory.
Modern models of the Universe are based on general theory relativity of A. Einstein. Einstein's equation of gravity has not one, but many solutions, which explains the existence of many cosmological models.
The first model was developed by A. Einstein in 1917. He rejected Newton's postulates about the absoluteness and infinity of space and time. In accordance with this model, world space is homogeneous and isotropic, matter in it is distributed evenly, gravitational attraction of masses is compensated by universal cosmological repulsion. The existence of the Universe is infinite, and space is limitless, but finite. Universe in cosmological model Einstein is stationary, infinite in time and limitless in space.
In 1922, Russian mathematician and geophysicist A.A. Friedman discarded the postulate of stationarity and obtained a solution to Einstein’s equation, which describes the Universe with “expanding” space. In 1927, the Belgian abbot and scientist J. Lemaitre based astronomical observations introduced the concept the beginning of the Universe as a superdense state and the birth of the Universe as the Big Bang. In 1929, the American astronomer E. P. Hubble discovered that all galaxies are moving away from us, and at a speed that increases in proportion to the distance - the galaxy system is expanding. The expansion of the Universe is considered a scientifically established fact. According to the calculations of J. Lemaitre, the radius of the Universe in its original state was 10 -12 cm, which
close in size to the electron radius, and its
the density was 10 96 g/cm 3 . From
From its initial state, the Universe began to expand as a result of the big bang. A. A. Friedman’s student G. A. Gamov suggested that the temperature of the substance after the explosion was high and fell with the expansion of the Universe. His calculations showed that the Universe in its evolution goes through certain stages, during which the formation of chemical elements and structures occurs.
Hadron era(heavy particles that enter into strong interactions). The duration of the era is 0.0001 s, the temperature is 10 12 degrees Kelvin, the density is 10 14 g/cm 3. At the end of the era, the annihilation of particles and antiparticles occurs, but a certain number of protons, hyperons, and mesons remain.
Era of leptons(light particles entering electromagnetic interaction). The duration of the era is 10 s, the temperature is 10 10 degrees Kelvin, the density is 10 4 g/cm 3. The main role is played by light particles that take part in reactions between protons and neutrons.
Photon era. Duration 1 million years. The bulk of the mass - the energy of the Universe - comes from photons. By the end of the era, the temperature drops from 10 10 to 3000 degrees Kelvin, density - from 10 4 g/cm 3 to 1021 g/cm 3. The main role is played by radiation, which at the end of the era is separated from matter.
Star era occurs 1 million years after the birth of the Universe. During the stellar era, the process of formation of protostars and protogalaxies begins.
Then a grandiose picture of the formation of the structure of the Metagalaxy unfolds.
Another hypothesis is the inflationary model of the Universe, which considers the creation of the Universe. The idea of creation is related to quantum cosmology. This model describes the evolution of the Universe, starting from the moment 10 -45 s after the start of expansion.
According to this hypothesis, cosmic evolution in the early Universe goes through a number of stages. The beginning of the universe is defined by theoretical physicists as state of quantum supergravity with a radius of the Universe of 10 -50 cm(for comparison: the size of an atom is defined as 10 -8 cm, and the size atomic nucleus 10-13 cm). The main events in the early Universe took place in a negligibly small period of time from 10-45 s to 10 -30 s.
Inflation stage. As a result of a quantum leap, the Universe passed into a state of excited vacuum and in the absence of matter and radiation intensely expanded according to exponential law. During this period, the space and time of the Universe itself was created. During the period of the inflationary stage lasting 10 -34 s, the Universe inflated from unimaginably small quantum sizes (10 -33) to unimaginably large (10 1000000) cm, which is many orders of magnitude greater than the size of the observable Universe - 10 28 cm. This entire initial period in the Universe was not there was no matter, no radiation.
Transition from the inflationary stage to the photon stage. The state of false vacuum disintegrated, the released energy went into the birth of heavy particles and antiparticles, which, after annihilation, gave a powerful flash of radiation (light) that illuminated space.
Stage of separation of matter from radiation: the substance remaining after annihilation became transparent to radiation, the contact between the substance and the radiation disappeared. The radiation separated from matter constitutes modern relic background is a residual phenomenon from the initial radiation that arose after the explosion at the beginning of the formation of the Universe. Subsequently, the development of the Universe went in the direction from the most simple homogeneous state to the creation of more and more complex structures– atoms (initially hydrogen atoms), galaxies, stars, planets, the synthesis of heavy elements in the bowels of stars, including those necessary for the creation of life, the emergence of life and, as the crown of creation, man.
The difference between the stages of the evolution of the Universe in the inflationary model and the Big Bang model This applies only to the initial stage of about 10–30 s, then there are no fundamental differences between these models. Differences in explanation of the mechanisms of cosmic evolution associated with ideological attitudes .
The first was the problem of the beginning and end of the existence of the Universe, the recognition of which contradicted the materialistic statements about eternity, uncreation and indestructibility, etc. of time and space.
In 1965, American theoretical physicists Penrose and S. Hawking proved a theorem according to which in any model of the Universe with expansion there must necessarily be a singularity - a break in time lines in the past, which can be understood as the beginning of time. The same is true for the situation when expansion is replaced by compression - then there will be a break in time lines in the future - the end of time. Moreover, the point at which the compression began is interpreted as the end of time - the Great Drain, into which not only galaxies flow, but also the “events” of the entire past of the Universe.
The second problem is related to the creation of the world out of nothing. A.A. Friedman mathematically deduces the moment of the beginning of the expansion of space with zero volume, and in his popular book “The World as Space and Time,” published in 1923, he talks about the possibility of “creating the world out of nothing.” An attempt to solve the problem of the emergence of everything from nothing was made in the 80s by the American physicist A. Gut and Soviet physicist A. Linde. The energy of the Universe, which is conserved, was divided into gravitational and non-gravitational parts, having different signs. And then total energy The universe will be zero.
The greatest difficulty for scientists arises in explaining the causes of cosmic evolution. There are two main concepts that explain the evolution of the Universe: the concept of self-organization and the concept of creationism.
For the concept of self-organization, the material Universe is the only reality, and no other reality exists besides it. In this case, evolution is described as follows: there is a spontaneous ordering of systems in the direction of the formation of increasingly complex structures. Dynamic chaos creates order. There is no goal of cosmic evolution.
Within the framework of the concept of creationism, that is, creation, the evolution of the Universe is associated with the implementation of a program determined by reality more high order, how material world. Proponents of creationism draw attention to the existence of directed development from simple systems to more complex and information-intensive ones, during which the conditions for the emergence of life and man were created. The existence of the Universe in which we live depends on the numerical values of fundamental physical constants - Planck's constant, constant gravity, etc. Numerical values These constants determine the main features of the Universe, the sizes of atoms, planets, stars, the density of matter and the lifetime of the Universe. From this it is concluded that physical structure The Universe is programmed and directed towards the emergence of life. The ultimate goal of cosmic evolution is the appearance of man in the Universe in accordance with the plans of the Creator.
Other unsolved problem– the further fate of the Universe. Will it continue to expand indefinitely or will this process reverse after some time and the compression stage begin? The choice between these scenarios can be made if data on gross weight substances in the Universe (or its average density), which are not yet sufficient.
If the energy density in the Universe is low, then it will expand forever and gradually cool down. If the energy density is greater than a certain critical value, then the expansion stage will be replaced by a compression stage. The universe will shrink in size and heat up.
Inflation model predicted that the energy density should be critical. However, astrophysical observations carried out before 1998 indicated that the energy density was approximately 30% of the critical one. But the discoveries of recent decades have made it possible to “find” the missing energy. It has been proven that a vacuum has positive energy (called dark energy), and it is evenly distributed in space (which again proves that there are no “invisible” particles in a vacuum).
Today, there are much more options for answering the question about the future of the Universe, and they significantly depend on which theory explaining hidden energy is correct. But we can say unequivocally that our descendants will see the world around us completely differently than you and I.
There are very reasonable suspicions that in addition to the objects we see in the Universe, there are also large quantity hidden, but also having mass, and this “dark mass” can be 10 or more times greater than the visible one.
Briefly, the characteristics of the Universe can be presented in this form.
Short biography Universe
Age: 13.7 billion years
Size of the observable part of the Universe:
13.7 billion light years, approximately 10 28 cm
Average density substances: 10 -29 g/cm 3
Weight: more than 10 50 tons
Weight at birth:
according to the Big Bang theory - infinite
according to inflation theory - less than a milligram
Temperature of the Universe:
at the moment of explosion – 10 27 K
modern – 2.7 K
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7. CONCLUSION
Collecting information about cosmic radiation and its impact on the environment, I became convinced that everything in the world is interconnected, everything flows and changes, and we constantly feel the echoes of the distant past, starting from the formation of the Universe.
Particles that have reached us from other galaxies carry with them information about distant worlds. These “space aliens” are capable of having a significant impact on nature and biological processes on our planet.
Everything is different in space: Earth and sky, sunsets and sunrises, temperature and pressure, speeds and distances. Much of it seems incomprehensible to us.
Space is not our friend yet. It confronts man as an alien and hostile force, and every astronaut, going into orbit, must be ready to fight it. This is very difficult, and a person does not always emerge victorious. But the more expensive the victory is, the more valuable it is.
The influence of outer space is quite difficult to assess; on the one hand, it led to the emergence of life and, ultimately, created man himself; on the other hand, we are forced to defend ourselves from it. In this case, it is obviously necessary to find a compromise and try not to destroy the fragile balance that currently exists.
Yuri Gagarin, seeing the Earth from space for the first time, exclaimed: “How small it is!” We must remember these words and take care of our planet with all our might. After all, we can only get into space from Earth.
8. BIBLIOGRAPHY.
1. Buldakov L.A., Kalistratova V.S. Radioactive radiation and health, 2003.
2. Levitan E.P. Astronomy. – M.: Education, 1994.
3. Parker Yu. How to protect space travelers. // In the world of science. - 2006, No. 6.
4. Prigozhin I.N. Past and future of the Universe. – M.: Knowledge, 1986.
5. Hawking S. Short story time from the big bang to black holes. – St. Petersburg: Amphora, 2001.
6. Encyclopedia for children. Cosmonautics. – M.: “Avanta+”, 2004.
7. http://www. rol. ru/ news/ misc/ spacenews/ 00/12/25. htm
8. http://www. grani. ru/Society/Science/m. 67908.html
Then this series of articles is for you... We will talk about natural sources of ionizing radiation, the use of radiation in medicine and other interesting things.
Sources of ionizing radiation are conventionally divided into two groups - natural and artificial. Natural sources have always existed, but artificial ones were created by human civilization in the 19th century. This is easy to explain using the example of two prominent scientists who are associated with the discovery of radiation. Antoine Henri Becquerel discovered ionizing radiation from uranium (a natural source), and Wilhelm Conrad Roentgen discovered ionizing radiation when electrons were decelerated, which were accelerated in a specially created device (an X-ray tube as artificial source). Let us analyze in percentage and digital equivalent what radiation doses ( quantitative characteristic the impact of ionizing radiation on the human body) the average citizen of Ukraine receives throughout the year from various artificial and natural sources (Fig. 1).
Rice. 1. Structure and weighted averages effective dose of radiation to the population of Ukraine per year
As you can see, we receive the bulk of radiation from natural sources of radiation. But have these natural sources remained the same as they were in the early stages of civilization? If so, there is no need to worry, because we have long adapted to such radiation. But, unfortunately, this is not the case. Human activity leads to the fact that natural radioactive sources concentrate and increase the possibility of their influence on humans.
One of the places where the possibility of radiation influencing humans increases is outer space. Intensity radiation exposure depends on altitude above sea level. Thus, astronauts, pilots and air transport passengers, as well as the population living in the mountains, receive an additional dose of radiation. Let's try to find out how dangerous this is for humans, and what “radiation” secrets space hides.
Radiation in space: what is the danger for astronauts?
It all started when the American physicist and astrophysicist James Alfred Van Allen decided to attach a Geiger-Muller counter to the first satellite that was launched into orbit. The indicators of this device officially confirmed the existence of a belt of intense radiation around the globe. But where did it come from in space? It is known that radioactivity has existed in space for a very long time, even before the appearance of the Earth, thus, outer space was constantly filled and is filled with radiation. After research, scientists came to the conclusion that radiation in space arises either from the sun, during flares, or from cosmic rays that arise as a result of high-energy events in our and other galaxies.
It was found that the radiation belts begin at 800 km above the Earth's surface and extend to 24,000 km. According to the classification of the International Aeronautics Federation, a flight is considered space if its altitude exceeds 100 km. Accordingly, astronauts are the most vulnerable to receiving a large dose of cosmic radiation. The higher they rise into outer space, the closer they are to the radiation belts, therefore, the greater the risk of receiving significant amounts of radiation.
The scientific director of the US National Aeronautics and Space Administration (NASA) program to study the effects of radiation on humans, Francis Cucinotta once noted that the most unpleasant consequence of space radiation during long-term flights of astronauts is the development of cataracts, that is, clouding of the lens of the eye. Moreover, there is a risk of cancer. But Cucinotta also noted that the astronauts did not experience any extremely dire consequences after the flight. He only emphasized that much is still unknown about how cosmic radiation affects astronauts and what the real consequences of this impact are.
The issue of protecting astronauts from radiation in space has always been a priority. Back in the 60s of the last century, scientists shrugged and did not know how to protect astronauts from cosmic radiation, especially when it was necessary to go into outer space. In 1966 Soviet cosmonaut still decided to go into outer space, but in a very heavy lead suit. Subsequently, technological progress shifted solutions to the problem from dead center, and lighter, safer suits were created.
The exploration of outer space has always attracted scientists, researchers and astronauts. The secrets of new planets may be useful for the further development of humanity on planet Earth, but they can also be dangerous. That's why Curiosity's mission to Mars was a big deal. But let’s not deviate from the main focus of the article and focus on the results of radiation exposure recorded by the corresponding instrument on board the rover. This device was located inside the spacecraft, so its readings indicate the real dose that an astronaut can receive already in a manned spacecraft. Scientists who processed the measurement results reported disappointing data: the equivalent radiation dose was 4 times greater than the maximum permissible for workers nuclear power plants. In Ukraine, the radiation dose limit for those who permanently or temporarily work directly with sources of ionizing radiation is 20 mSv.
To explore the most remote corners of space, it is necessary to carry out missions that cannot technically be carried out using traditional sources energy. This issue was resolved through the use of nuclear energy sources, namely isotope batteries and reactors. These sources are unique in their kind because they have a high energy potential, which significantly expands the capabilities of missions in outer space. For example, probe flights to the outer boundaries of the solar system have become possible. Since the duration of such flights is quite long, the panels solar panels not suitable as a power source for spacecraft.
The other side of the coin is the potential risks associated with the use of radioactive sources in space. Basically, this is a danger of unforeseen or emergency circumstances. That is why states that launch space objects with nuclear power sources on board make every effort to protect individuals, populations and the biosphere from radiological hazards. Such conditions were defined in the principles relating to the use of nuclear power sources in outer space, and were adopted in 1992 by a resolution of the United Nations (UN) General Assembly. The same principles also stipulate that any state that launches a space object with nuclear power sources on board must promptly inform interested countries if a malfunction appears at the space object and there is a danger of radioactive materials returning to Earth.
Also, the United Nations, together with the International Agency for atomic energy(IAEA) have developed a framework for ensuring safe use nuclear power sources in outer space. They are intended to complement the IAEA safety standards with high-level guidance that takes into account additional safety measures for the use of nuclear power sources on space assets during all mission phases: launch, operation and decommissioning.
Should I be afraid of radiation when using air transport?
Cosmic rays carrying radiation reach almost all corners of our planet, but the spread of radiation is not proportional. The Earth's magnetic field deflects a significant number of charged particles from equatorial zone, thereby focusing more radiation on the North and South Poles. Moreover, as already noted, cosmic irradiation depends on altitude. Those living at sea level receive approximately 0.003 mSv per year from cosmic radiation, while those living at 2 km level may receive twice as much radiation.
As is known, with a cruising speed for passenger airliners of 900 km/h, taking into account the ratio of air resistance and lift, the optimal flight altitude for an aircraft is usually approximately 9-10 km. So when an airliner rises to such a height, the level of radiation exposure can increase almost 25 times from what it was at the 2 km mark.
Passengers on transatlantic flights are exposed to the greatest amount of radiation per flight. When flying from the USA to Europe, a person may receive an additional 0.05 mSv. The fact is that the earth’s atmosphere has appropriate shielding protection from cosmic radiation, but when an airliner is raised to the above-mentioned optimal altitude, this protection partially disappears, which leads to additional radiation exposure. That is why frequent flights across the ocean increase the risk of the body receiving an increased dose of radiation. For example, 4 such flights could cost a person a dose of 0.4 mSv.
If we talk about pilots, the situation here is somewhat different. Because they frequently fly across the Atlantic, the radiation dose to airline pilots can exceed 5 mSv per year. By the standards of Ukraine, when receiving such a dose, persons are already equated to another category - people who are not directly involved in working with sources of ionizing radiation, but due to the location of workplaces in premises and on industrial sites of facilities with radiation-nuclear technologies, they may receive additional exposure. For such persons, the radiation dose limit is set at 2 mSv per year.
The International Atomic Energy Agency has shown significant interest in this issue. The IAEA has developed a number of safety standards, and the problem of exposure of aircraft crews is also reflected in one of these documents. According to the Agency's recommendations, the national regulatory authority or other appropriate and competent authority is responsible for establishing the reference dose level for aircraft crews. If this dose is exceeded, aircraft crew employers must carry out appropriate measures to assess doses and record them. Moreover, they must inform female aircraft crew members about the risks associated with exposure to cosmic radiation to the embryo or fetus and the need for early warning of pregnancy.
Can space be considered as a place for disposing of radioactive waste?
We have already seen that cosmic radiation, although it does not have catastrophic consequences for humanity, can increase the level of human radiation. While assessing the impact of cosmic rays on humans, many scientists are also studying the possibility of using outer space for the needs of mankind. In the context of this article, the idea of burial looks very ambiguous and interesting radioactive waste in space.
The fact is that scientists from countries, where they are actively used nuclear energy, are constantly searching for places to safely contain radioactive waste, which is constantly accumulating. Outer space has also been considered by some scientists as a potential location for hazardous waste. For example, specialists from the State design bureau Yuzhnoye, which is located in Dnepropetrovsk, together with the International Academy of Astronautics is studying the technical components of implementing the idea of burying waste in deep space.
On the one hand, sending such waste into space is very convenient, since it can be carried out at any time and in unlimited quantities, which removes the question of the future of this waste in our ecosystem. Moreover, as experts note, such flights do not require great precision. But on the other hand, this method also has weak sides. The main problem is ensuring safety for the Earth's biosphere at all stages of launching a launch vehicle. The probability of an accident during startup is quite high, and is estimated at almost 2-3%. A fire or explosion of a launch vehicle at launch, during flight, or its fall can cause a significant dispersion of hazardous radioactive waste. That is why, when studying this method, the main attention should be focused on the issue of safety in any emergency situations.
Olga Makarovskaya, Deputy Chairman of the State Nuclear Regulatory Authority of Ukraine; Dmitry Chumak, leading engineer of the information support sector of the Information and Technical Department of the SSTC NRS, 03/10/2014
https://site/wp-content/uploads/2015/09/diagram11.jpg 450 640 admin //site/wp-content/uploads/2017/08/Logo_Uatom.pngadmin 2015-09-29 09:58:38 2017-11-06 10:52:43 Radiation and space: what you need to know? (“Radiation” secrets that outer space hides)