Approximate level of radiation in space. What is cosmic radiation? Sources, danger

Where μ – mass attenuation coefficient of X-ray radiation cm 2 /g, X/ ρ – mass thickness of the protection g/cm2. If several layers are considered, then under the exponent there are several terms with a minus sign.

Absorbed radiation dose rate from X-rays per unit time N determined by radiation intensity I and mass absorption coefficient μ EN

N = μ EN I

For calculations, the mass extinction and absorption coefficients for different meanings X-ray energies are taken according to NIST X-Ray Mass Attenuation Coefficients.

Table 1 shows the parameters used and the calculation results for the absorbed and equivalent radiation dose from the protection.

Table 1. Characteristics of X-ray radiation, attenuation coefficients in Al and absorption coefficients in the body, thickness of protection, result of calculation of absorbed and equivalent radiation dose per day*

*Note – the thickness of the protection of LM-5 and the Krechet, XA-25 and XA-15 spacesuits in aluminum equivalent, which corresponds to 5.6, 1.3, 0.9 and 0.6 mm of sheet aluminum; thickness of protection “ХО-25”, “Orlan-M” and A7L of tissue-equivalent substance, which corresponds to 2.3, 1.9 and 1.5 mm of tissue-equivalent substance.

This table is used to estimate the radiation dose per day for other values ​​of X-ray radiation intensity, multiplying by the coefficient of the ratio between the tabulated flux value and the desired average per day. The calculation results are shown in Fig. 3 and 4 in the form of a scale of absorbed radiation dose.

Calculations show that the lunar module with a protection of 1.5 g/cm 2 (or 5.6 mm Al) completely absorbs soft and hard x-ray radiation Sun. For the most powerful flare of November 4, 2003 (as of 2013 and recorded since 1976), the intensity of its X-ray radiation at the peak was 28·10−4 W/m2 for soft radiation and 4·10−4 W/m2 for hard radiation. The average intensity per day will be, respectively, 10 W/m2 day and 1.3 W/m2. The radiation dose for the crew per day is 8 rad or 0.08 Gy, which is safe for humans.

The probability of events like November 4, 2003, is determined to be 30 minutes in 37 years. Or equal to ~1/650000 hour−1. This is a very low probability. For comparison, the average person spends ~300,000 hours outside the home in his entire life, which corresponds to the possibility of being an eyewitness to the X-ray event of November 4, 2003 with a probability of 1/2.

To determine the radiation requirements for a spacesuit, we consider X-ray flares on the Sun, when their intensity increases 50 times for soft radiation and 1000 times for hard radiation relative to the average daily background of maximum solar activity. According to Fig. 4, the probability of such events is 3 outbreaks in 30 years. The intensity for soft X-ray radiation will be equal to 4.3 Watt/m2 day and for hard X-ray radiation - 0.26 W/m2.

Radiation requirements and parameters of a lunar spacesuit

In a spacesuit on the lunar surface, the equivalent radiation doses from X-rays increase.

When using the “Krechet” spacesuit for table values radiation intensity, the radiation dose will be 5 mrad/day. Protection against X-ray radiation is provided by 1.2-1.3 mm of aluminum sheet, reducing the radiation intensity by ~e9=7600 times. When using a smaller thickness of aluminum sheet, the radiation doses increase: for 0.9 mm Al – 15 mrad/day, for 0.6 mm Al – 120 mrad/day.

According to the IAEA, such background radiation is recognized as a normal condition for humans.

When the radiation power from the Sun increases to a value of 0.86 Watt/m 2 day, the radiation dose for protection of 0.6 mm Al is equal to 1.2 rad/ess, which is on the border of normal and dangerous conditions for human health.

Lunar spacesuit “Krechet”. View of the open backpack hatch through which the astronaut enters the spacesuit. As part of the Soviet lunar program, it was necessary to create a spacesuit that would allow sufficient long time work directly on the Moon. It was called “Krechet” and became the prototype of the “Orlan” spacesuits, which are used today for work in outer space. Weight 106 kg.

The radiation dose increases by an order of magnitude when using tissue-equivalent protection (polymers such as mylar, nylon, felt, fiberglass). So for the Orlan-M spacesuit, with protection of 0.21 g/cm 2 of tissue-equivalent substance, the radiation intensity decreases by ~e3=19 times and the radiation dose from X-ray radiation for the bone tissue of the body will be 1.29 rad/essence. For protection 0.25 g/cm 2 and 0.17 g/cm 2, respectively, 1.01 and 1.53 rad/ess.

Apollo 16 crew John Young (commander), Thomas Mattingly (command module pilot) and Charles Duke (lunar module pilot) wearing the A7LB spacesuit. It is difficult to put on such a spacesuit on your own.

Eugene Cernan in A7LB spacesuit, Apollo 17 mission.

A7L - the main type of spacesuit used by NASA astronauts in the Apollo program until 1975. Sectional view of the outerwear. Outerwear included: 1) fire-resistant fiberglass fabric weighing 2 kg, 2) screen-vacuum thermal insulation(EVTI) to protect a person from overheating when in the Sun and from excessive heat loss on the unlit surface of the Moon, is a package of 7 layers of thin film of Mylar and nylon with a shiny aluminized surface, the thinnest veil of Dacron fibers is laid between the layers, the weight was 0. 5 kg; 3) an anti-meteor layer made of nylon with a neoprene coating (3–5 mm thick) and weighing 2–3 kg. The inner shell of the spacesuit was made of durable fabric, plastic, rubberized fabric and rubber. The mass of the inner shell is ~20 kg. The kit included a helmet, mittens, boots and coolant. Weight of the A7L extravehicular space suit set is 34.5 kg

With an increase in the intensity of radiation from the Sun to a value of 0.86 Watt/m 2 day, the radiation dose for protection of 0.25 g/cm 2 , 0.21 g/cm 2 and 0.17 g/cm 2 of tissue equivalent substance, respectively, is 10 .9, 12.9 and 15.3 rad/ess. This dose is equivalent to 500-700 human chest x-ray procedures. A single dose of 10-15 rad affects nervous system and psyche, the risk of developing blood leukemia increases by 5%, mental retardation is observed in the descendants of parents. According to the IAEA, such background radiation poses a very serious danger to humans.

With an X-ray radiation intensity of 4.3 Watt/m 2 day, the radiation dose per day is 50-75 rad and causes radiation diseases.

Cosmonaut Mikhail Tyurin in the Orlan-M spacesuit. The suit was used at the MIR station and the ISS from 1997 to 2009. Weight 112 kg. Currently, the ISS uses Orlan-MK (modernized, computerized). Weight 120 kg.

The simplest way out is to reduce the time an astronaut spends under the direct rays of the Sun to 1 hour. The absorbed dose of radiation in the Orlan-M spacesuit will decrease to 0.5 rad. Another approach is to work in the shadows space station, in this case the duration of extravehicular activity can be significantly increased, despite the high external X-ray radiation. If you are on the surface of the Moon far beyond the lunar base, a quick return and shelter is not always possible. You can use the shadow of the lunar landscape or an umbrella from X-ray rays...

A simple, effective way to protect against X-ray radiation from the Sun is to use sheet aluminum in a spacesuit. At 0.9 mm Al (thickness 0.25 g/cm 2 in aluminum equivalent), the suit has a 67-fold margin from the average X-ray background. With a 10-fold increase in background to 0.86 Watt/m 2 day, the radiation dose is 0.15 rad/day. Even with a sudden 50-fold increase in the X-ray flux from the average background to a value of 4.3 Watt/m 2 day, the absorbed radiation dose per day will not exceed 0.75 rad.

At 0.7 mm Al (thickness 0.20 g/cm 2 in aluminum equivalent), the protection maintains a 35-fold radiation margin. At 0.86 Watt/m2 day, the radiation dose will be no more than 0.38 rad/day. At 4.3 Watt/m2 day, the absorbed radiation dose will not exceed 1.89 rad.

Calculations show that to provide radiation protection of 0.25 g/cm 2 in aluminum equivalent, a tissue equivalent of 1.4 g/cm 2 is required. With this value of mass protection of the spacesuit, its thickness will increase several times and reduce its usability.

RESULTS AND CONCLUSIONS

In the case of proton radiation, tissue-equivalent protection has a 20-30% advantage over aluminum.

When exposed to X-ray radiation, suit protection in aluminum equivalent is preferred over polymers. This conclusion coincides with the results of research by David Smith and John Scalo.

Lunar spacesuits must have two protection parameters:

1) parameter for protecting a spacesuit with tissue-equivalent substances from proton radiation, not lower than 0.21 g/cm 2 ;
2) the protection parameter of the spacesuit in aluminum equivalent from X-ray radiation, not lower than 0.20 g/cm 2 .

When using Al protection in the outer shell of a spacesuit with an area of ​​2.5-3 m2, the weight of the spacesuit based on Orlan-MK will increase by 5-6 kg.

For a lunar spacesuit, the total absorbed dose of radiation from the solar wind and X-rays from the Sun in the year of maximum solar activity will be 0.19 rad/day (equivalent radiation dose – 8.22 mSv/day). Such a spacesuit has a 4-fold radiation safety margin for solar wind and a 35-fold radiation safety margin for X-ray radiation. No additional protective measures, such as aluminum radiation umbrellas, are needed.

For the Orlan-M spacesuit, respectively, 1.45 rad/day (equivalent radiation dose - 20.77 mSv/day). The suit has a 4-fold radiation safety margin for solar wind.

For the A7L (A7LB) spacesuit of the Apollo mission, respectively, 1.70 rad/day (equivalent radiation dose - 23.82 mSv/day). The suit has a 3-fold radiation safety margin for solar wind.

When continuously staying for 4 days on the surface of the Moon in modern Orlan or A7L type spacesuits, a person gains a radiation dose of 0.06-0.07 Gy, which poses a danger to his health. This is consistent with the findings of David Smith and John Scalo , that in cislunar outer space in a modern spacesuit, within 100 hours, with a probability of 10%, a person will receive a dose of radiation above 0.1 Gray that is dangerous to health and life. Orlan or A7L type spacesuits require additional X-ray protection measures, such as aluminum radiation umbrellas.

The proposed lunar spacesuit at the Orlan base gains a radiation dose of 0.76 rad or 0.0076 Gy in 4 days. (One hour of exposure to the solar wind on the lunar surface in a spacesuit corresponds to two chest x-rays.) According to the IAEA, radiation risk is recognized as a normal condition for humans.

NASA is testing a new space suit for the upcoming 2020 manned flight to the Moon.

In addition to the radiation risk from the solar wind and X-rays from the Sun, there is a flux. More on this later.

Original taken from sokolov9686 in So were the Americans on the moon?...

Above 24,000 km above the Earth, radiation kills all living things

As already mentioned, as soon as the Americans began their space program, their scientist James Van Allen made a rather important discovery. First American artificial satellite, which they launched into orbit, was much smaller than the Soviet one, but Van Allen thought of attaching a Geiger counter to it. Thus, what was expressed at the end of the 19th century was officially confirmed. The outstanding scientist Nikola Tesla hypothesized that the Earth is surrounded by a belt of intense radiation.

Photograph of Earth by astronaut William Anders during the Apollo 8 mission (NASA archives)

Tesla, however, was considered a great eccentric, and even a madman by academic science, so his hypotheses about the gigantic electric charge generated by the Sun were shelved for a long time, and the term “solar wind” did not cause anything but smiles. But thanks to Van Allen, Tesla's theories were revived. At the instigation of Van Allen and a number of other researchers, it was found that radiation belts in space begin at 800 km above the Earth's surface and extend up to 24,000 km. Since the radiation level there is more or less constant, the incoming radiation should be approximately equal to the outgoing radiation. Otherwise, it would either accumulate until it “baked” the Earth, as in an oven, or it would dry up. Regarding this, Van Allen wrote:

“Radiation belts can be compared to a leaky vessel that is constantly replenished from the Sun and leaks into the atmosphere. A large portion of solar particles overflows the vessel and splashes out, especially in the polar zones, leading to polar lights, magnetic storms and other similar phenomena.”

Radiation from the Van Allen belts depends on the solar wind. In addition, they appear to focus or concentrate this radiation within themselves. But since they can only concentrate in themselves what came directly from the Sun, one more question remains open: how much radiation is in the rest of the cosmos?

NASA | Heliophysics | The satellite has discovered a new radiation belt!

about Van Allen rings 28.30 minute radiation kills everything

There are a bunch of museums in Europe where regolith is displayed in fairly large pieces for free viewing. If you don’t believe me, the addresses of the museums are there, it’s easy to check.

For example, here is a stone in the Toulouse Cité de l'Espace:

Original taken from toomth V Why is NASA hiding “lunar soil” from the whole world?

It is believed that the Americans brought 378 kg of lunar soil and rocks from the Moon. At least that's what NASA says. This is almost four centners. It is clear that only astronauts could deliver such an amount of soil: no space stations can do this.

The rocks have been photographed, transcribed, and are regular extras in NASA's lunar films. In many of these films, the role of an expert and commentator is played by the Apollo 17 astronaut-geologist, Dr. Harrison Schmidt, who allegedly personally collected many of these stones on the Moon

It is logical to expect that with such lunar wealth, America will shock them, demonstrate them in every possible way, and even to someone, and will give away 30-50 kilograms of bounty to its main rival. Here, they say, research, make sure of our successes... But for some reason this just doesn’t work out. They gave us little soil. But “theirs” (again, according to NASA) received 45 kg of lunar soil and stones.

True, some particularly meticulous researchers carried out calculations based on the relevant publications of scientific centers and could not find convincing evidence that these 45 kg reached the laboratories of even Western scientists. Moreover, according to them, it turns out that currently no more than 100 g of American lunar soil wanders from laboratory to laboratory in the world, so that a researcher usually received half a gram of rock.

That is, NASA refers to lunar soil as stingy knight to gold: he keeps the treasured centners in his basements in securely locked chests, giving out only measly grams to researchers. The USSR did not escape this fate either.

In our country at that time, the leading scientific organization for all studies of lunar soil was the Institute of Geochemistry of the USSR Academy of Sciences (now GEOKHI RAS). The head of the meteoritics department of this institute is Dr. M.A. Nazarov reports: “The Americans transferred to the USSR 29.4 grams (!) of lunar regolith (in other words, lunar dust) from all Apollo expeditions, and from our collection of samples “Luna-16, 20 and 24” were issued abroad 30.2 g." In fact, the Americans exchanged lunar dust with us, which can be delivered by any automatic station, although the astronauts should have brought weighty cobblestones, and the most interesting thing is to look at them.

What is NASA going to do with the rest of the lunar goodness? Oh, it's a "song".

“In the USA, a decision was made to keep the bulk of the delivered samples completely intact until new, more advanced ways of studying them are developed,” write competent Soviet authors, from whose pens more than one book on lunar soil has been published.

"It is necessary to spend minimal amount material, leaving the majority of each individual sample untouched and uncontaminated for study by future generations of scientists,” explains NASA’s position, American specialist J. A. Wood.

Obviously, the American specialist believes that no one will fly to the Moon ever again - neither now nor in the future. And therefore we need to protect the centners of lunar soil better than our eyes. At the same time, modern scientists are humiliated: with their instruments they can examine every single atom in a substance, but they are denied trust - they are not mature enough. Or they didn’t come out with their snout. This persistent concern of NASA for future scientists is more likely to be a convenient excuse to hide the disappointing fact: in its storerooms there are neither lunar rocks nor quintals of lunar soil.

Another strange thing: after the completion of the “lunar” flights, NASA suddenly began to experience an acute shortage of money for their research.

Here is what one of the American researchers writes as of 1974: “A significant part of the samples will be stored as a reserve at the space flight center in Houston. Reducing funding will reduce the number of researchers and slow the pace of research."

After spending $25 billion to deliver lunar samples, NASA suddenly discovered that there was no money left for their research...

The story of the exchange of Soviet and American soil is also interesting. Here is a message from April 14, 1972, the main official publication of the Soviet period, the Pravda newspaper:

“On April 13, representatives of NASA visited the Presidium of the USSR Academy of Sciences. The transfer of lunar soil samples from those delivered to Earth by the Soviet automatic station “Luna-20” took place. At the same time, Soviet scientists were given a sample of lunar soil obtained by the crew of the American spacecraft Apollo 15. The exchange was made in accordance with an agreement between the USSR Academy of Sciences and NASA, signed in January 1971.”

Now we need to go through the deadlines.

July 1969 The Apollo 11 astronauts allegedly brought back 20 kg of lunar soil. The USSR does not give anything from this amount. At this point, the USSR does not yet have lunar soil.

September 1970 Our Luna-16 station delivers lunar soil to Earth, and from now on, Soviet scientists have something to offer in exchange. This puts NASA in a difficult position. But NASA expects that at the beginning of 1971 it will be able to automatically deliver its lunar soil to Earth, and with this in mind, an exchange agreement has already been concluded in January 1971. But the exchange itself does not take place for another 10 months. Apparently, something went wrong with automatic delivery in the USA. And the Americans are starting to drag their feet.

July 1971 As a matter of goodwill, the USSR unilaterally transfers 3 g of soil from Luna-16 to the United States, but receives nothing from the United States, although the exchange agreement was signed six months ago, and NASA supposedly already has 96 kg of lunar soil in its storerooms (from “ Apollo 11, Apollo 12 and Apollo 14). Another 9 months pass.

April 1972 NASA is finally handing over a sample of lunar soil. It was allegedly delivered by the crew of the American spacecraft Apollo 15, although 8 months have already passed since the flight of Apollo 15 (July 1971). By this time, NASA supposedly already had 173 kg of lunar rocks in its storerooms (from Apollo 11, Apollo 12, Apollo 14 and Apollo 15).

Soviet scientists receive from these riches a certain sample, the parameters of which are not reported in the Pravda newspaper. But thanks to Dr. M.A. Nazarov, we know that this sample consisted of regolith and did not exceed 29 g in mass.

It's very likely that until about July 1972, the United States had no real lunar soil at all. Apparently, somewhere in the first half of 1972, the Americans acquired the first grams of real lunar soil, which was delivered from the Moon automatically. It was only then that NASA showed its readiness to make an exchange.

And in recent years, the Americans’ lunar soil (more precisely, what they pass off as lunar soil) has begun to disappear altogether. Summer 2002 great amount samples of lunar substance - a safe weighing almost 3 centners - disappeared from the storerooms of the museum of the American NASA Space Center. Johnson in Houston.

Have you ever tried to steal a 300 kg safe from the space center? And don't try: it's too heavy and dangerous job. But the thieves, on whose trail the police found it surprisingly quickly, easily succeeded. Tiffany Fowler and Ted Roberts, who worked in the building during the period of their disappearance, were arrested by special agents of the FBI and NASA in a restaurant in Florida. Subsequently, the third accomplice, Shae Saur, was taken into custody in Houston, and then the fourth participant in the crime, Gordon Mac Water, who contributed to the transportation of stolen goods. The thieves intended to sell priceless evidence of NASA's lunar mission at a price of $1000-5000 per gram through the website of a mineralogy club in Antwerp (Holland). The value of the stolen goods, according to information from overseas, was more than $1 million.

A few years later - a new misfortune. In the United States, in the Virginia Beach area, two small sealed disk-shaped plastic boxes with samples of meteorite and lunar substances, judging by the markings on them, were stolen from a car by unknown thieves. Samples of this kind, Space reports, are transferred by NASA to special instructors “for training purposes.” Before receiving such samples, teachers undergo special training, during which they are taught how to properly handle this US national treasure. And “national treasure”, it turns out, is so easy to steal... Although this does not look like a theft, but like a staged theft in order to get rid of evidence: no ground - no “inconvenient” questions.

Even if interplanetary flights were a reality, scientists are increasingly saying that human body from a purely biological point of view, more and more dangers await. Experts call hard cosmic radiation one of the main dangers. On other planets, for example on Mars, this radiation will be such that it will significantly accelerate the onset of Alzheimer's disease.

"Cosmic radiation poses a very significant threat to future astronauts. The possibility that cosmic radiation exposure could lead to health problems such as cancer has long been recognized," says Kerry O'Banion, a neuroscience doctor from Medical center at the University of Rochester. "Our experiments also reliably established that hard radiation also provokes an acceleration of changes in the brain associated with Alzheimer's disease."

According to scientists, everything space literally permeated with radiation, while the thick earth's atmosphere protects our planet from it. Participants in short-term flights to the ISS can already feel the effects of radiation, although formally they are in low orbit, where the protective dome of Earth’s gravity is still working. Radiation is especially active at those moments when flares occur on the Sun with subsequent emissions of radiation particles.

Scientists say that NASA is already working closely on different approaches related to human protection from cosmic radiation. The space agency first began funding “radiation research” 25 years ago. Now Substantial part initiatives in this area involve research into how to protect future marsonauts from harsh radiation on the Red Planet, which does not have the same atmospheric dome as on Earth.

Already, experts say with a very high probability that Martian radiation provokes cancer. There are even larger amounts of radiation near asteroids. Let us remind you that NASA plans a mission to an asteroid with human participation for 2021, and to Mars no later than 2035. A trip to Mars and back, with some time spent there, could take about three years.

As NASA said, it has now been proven that space radiation provokes, in addition to cancer, diseases of the cardiovascular system, musculoskeletal and endocrine. Now experts from Rochester have identified another vector of danger: as part of the research, it was found that high doses Cosmic radiation provokes diseases associated with neurodegeneration, in particular, they activate processes that contribute to the development of Alzheimer's disease. Experts also studied how cosmic radiation affects the human central nervous system.

Based on experiments, experts have established that radioactive particles in space have in their structure the nuclei of iron atoms, which have phenomenal penetrating ability. This is why it is surprisingly difficult to defend against them.

On Earth, researchers carried out simulations of cosmic radiation at the American Brookhaven National Laboratory on Long Island, where a special particle accelerator is located. Through experiments, researchers determined the time frame during which the disease occurs and progresses. However, so far the researchers have been conducting experiments on laboratory mice, exposing them to doses of radiation comparable to those that people would receive during a flight to Mars. After the experiments, almost all the mice suffered disturbances in the functioning of the cognitive system of the brain. Disturbances in the functioning of the cardiovascular system were also noted. Foci of accumulation of beta-amyloid, a protein that is a sure sign of impending Alzheimer's disease, have been identified in the brain.

Scientists say they don't yet know how to combat space radiation, but they are confident that radiation is a factor that deserves the most serious attention when planning future space flights.

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 an 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 average values ​​of the effective radiation dose of 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. The intensity of radiation exposure depends on the 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, a Soviet cosmonaut finally decided to go into outer space, but in a very heavy lead suit. Subsequently, technological progress advanced solutions to the problem, and lighter and 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 dose for nuclear plant workers. In Ukraine, the radiation dose limit for those who permanently or temporarily work directly with sources of ionizing radiation is 20 mSv.

Exploring the farthest corners of space requires missions that cannot technically be accomplished using traditional energy sources. 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 borders have become possible solar system. 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 Atomic Energy Agency (IAEA), has developed a framework to ensure the safe use of nuclear power sources in outer space. They are intended to complement the IAEA safety standards with guidance high level, taking into account additional safety measures when using nuclear power sources on space objects during all stages of missions: 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 amount of charged particles from the equatorial zone, thereby concentrating more radiation in 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 associated exposure cosmic radiation risk to the embryo or fetus and the need for early notification 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 ​​burying radioactive waste in space looks very ambiguous and interesting.

The fact is that scientists in countries where nuclear energy is actively used 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 Yuzhnoye State Design Bureau, which is located in Dnepropetrovsk, together with the International Academy of Astronautics are 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