Is there radiation in space? Cosmic rays and radiation
Since their appearance on Earth, all organisms have existed, developed and evolved under constant exposure to radiation. Radiation is the same natural phenomenon as wind, tides, rain, etc.
Natural background radiation (NBR) was present on Earth at all stages of its formation. It was there long before life and then the biosphere appeared. Radioactivity and the accompanying ionizing radiation were a factor that influenced current state biosphere, evolution of the Earth, life on Earth and elemental composition solar system. Any organism is exposed to the radiation background characteristic of a given area. Until the 1940s it was caused by two factors: the decay of radionuclides of natural origin, located both in the habitat of a given organism and in the organism itself, and cosmic rays.
Sources of natural (natural) radiation are space and natural radionuclides contained in natural form and concentrations in all objects of the biosphere: soil, water, air, minerals, living organisms, etc. Any of the objects around us and we ourselves are radioactive in the absolute sense of the word.
The world's population receives the main dose of radiation from natural sources radiation. Most of them are such that it is absolutely impossible to avoid exposure to radiation from them. Throughout the history of the Earth different types radiation penetrates the earth's surface from space and comes from radioactive substances located in the earth's crust. A person is exposed to radiation in two ways. Radioactive substances can be outside the body and irradiate it from the outside (in this case we talk about external irradiation) or they can end up in the air that a person breathes, in food or water and get inside the body (this method of irradiation is called internal).
Any inhabitant of the Earth is exposed to radiation from natural sources of radiation. This depends, in part, on where people live. Radiation levels in some places on the globe, especially where radioactive rocks occur, are significantly higher than average, and in other places they are lower. Terrestrial sources of radiation are collectively responsible for the majority of exposure to which humans are exposed through natural radiation. On average, they provide more than 5/6 of the annual effective equivalent dose received by the population, mainly due to internal exposure. The rest is contributed by cosmic rays, mainly through external irradiation.
The natural radiation background is formed by cosmic radiation (16%) and radiation created by radionuclides scattered in nature contained in the earth's crust, surface air, soil, water, plants, food, in animal and human organisms (84%). Technogenic background radiation is associated mainly with the processing and movement of rocks, the combustion of coal, oil, gas and other fossil fuels, as well as with testing nuclear weapons and nuclear energy.
Natural background radiation is an integral environmental factor that has a significant impact on human life. Natural background radiation varies widely in different regions of the Earth. The equivalent dose in the human body is on average 2 mSv = 0.2 rem. Evolutionary development shows that in natural conditions, optimal conditions are provided for the life of humans, animals, and plants. Therefore, when assessing the hazards caused by ionizing radiation, it is critical to know the nature and levels of exposure from various sources.
Since radionuclides, like any atoms, form certain compounds in nature and, in accordance with their chemical properties are part of certain minerals, the distribution of natural radionuclides in the earth’s crust is uneven. Cosmic radiation, as mentioned above, also depends on a number of factors and can differ several times. Thus, the natural background radiation is different in different places on the globe. This is related to the convention of the concept of “normal radiation background”: with altitude above sea level, the background increases due to cosmic radiation, in places where granites or thorium-rich sands come to the surface, the background radiation is also higher, and so on. Therefore, we can only talk about the average natural radiation background for a given area, territory, country, etc.
The average effective dose received by an inhabitant of our planet from natural sources per year is 2.4 mSv .
Approximately 1/3 of this dose is formed due to external radiation (approximately equally from space and from radionuclides) and 2/3 is due to internal radiation, that is, natural radionuclides located inside our body. The average human specific activity is about 150 Bq/kg. Natural background radiation (external exposure) at sea level averages about 0.09 μSv/h. This corresponds to approximately 10 µR/h.
Cosmic radiation is a stream of ionizing particles that falls to Earth from outer space. The composition of cosmic radiation includes:
Cosmic radiation consists of three components that differ in origin:
1) radiation from particles captured magnetic field Earth;
2) galactic cosmic radiation;
3) corpuscular radiation from the Sun.
Radiation from charged particles captured by the Earth's magnetic field - at a distance of 1.2-8 Earth radii there are so-called radiation belts containing protons with an energy of 1-500 MeV (mainly 50 MeV), electrons with an energy of about 0.1-0.4 MeV and a small amount of alpha particles.
Compound. Galactic cosmic rays are composed primarily of protons (79%) and alpha particles (20%), reflecting the abundance of hydrogen and helium in the Universe. Among the heavy ions highest value have iron ions due to their relatively high intensity and large atomic number.
Origin. The sources of galactic cosmic rays are stellar flares, supernova explosions, pulsar acceleration, explosions of galactic nuclei, etc.
Lifetime. The lifetime of particles in cosmic radiation is about 200 million years. Confinement of particles occurs due to the magnetic field of interstellar space.
Interaction with the atmosphere . Entering the atmosphere, cosmic rays interact with atoms of nitrogen, oxygen and argon. Particles collide with electrons more often than with nuclei, but high-energy particles lose little energy. In collisions with nuclei, particles are almost always eliminated from the flow, so the weakening of primary radiation is almost entirely due to nuclear reactions.
When protons collide with nuclei, neutrons and protons are knocked out of the nuclei, and nuclear fission reactions occur. The resulting secondary particles have significant energy and themselves induce the same nuclear reactions, i.e., a whole cascade of reactions is formed, the so-called broad atmospheric shower is formed. A single high-energy primordial particle can produce a shower of ten successive generations of reactions producing millions of particles.
New nuclei and nucleons, which make up the nuclear-active component of radiation, are formed mainly in the upper layers of the atmosphere. In its lower part, the flow of nuclei and protons is significantly weakened due to nuclear collisions and further ionization losses. At sea level it generates only a few percent of the dose rate.
Cosmogenic radionuclides
As a result of nuclear reactions occurring under the influence of cosmic rays in the atmosphere and partly in the lithosphere, radioactive nuclei are formed. Of these, the greatest contribution to dose creation is made by (β-emitters: 3 H (T 1/2 = 12.35 years), 14 C (T 1/2 = 5730 years), 22 Na (T 1/2 = 2.6 years) - entering the human body with food. As follows from the data presented, the largest contribution to radiation comes from carbon-14. An adult consumes ~ 95 kg of carbon per year with food.
Solar radiation, consisting of electromagnetic radiation up to the X-ray range, protons and alpha particles;
Listed species radiations are primary, they almost completely disappear at an altitude of about 20 km due to interaction with the upper layers of the atmosphere. In this case, secondary cosmic radiation is formed, which reaches the surface of the Earth and affects the biosphere (including humans). Secondary radiation includes neutrons, protons, mesons, electrons and photons.
The intensity of cosmic radiation depends on a number of factors:
Changes in the flux of galactic radiation,
Sun activity,
Geographical latitude,
Altitudes above sea level.
Depending on the altitude, the intensity of cosmic radiation increases sharply.
Radionuclides earth's crust.
Long-lived (with a half-life of billions of years) isotopes that did not have time to decay during the existence of our planet are scattered in the earth's crust. They probably formed simultaneously with the formation of the planets of the Solar System (relatively short-lived isotopes decayed completely). These isotopes are called natural radioactive substances, which means those that were formed and are constantly being re-formed without human intervention. As they decay, they form intermediate, also radioactive, isotopes.
External sources of radiation are more than 60 natural radionuclides found in the Earth's biosphere. Natural radioactive elements are contained in relatively small quantities in all the shells and core of the Earth. Of particular importance for humans are the radioactive elements of the biosphere, i.e. that part of the Earth’s shell (litho-, hydro- and atmosphere) where microorganisms, plants, animals and humans are located.
For billions of years, there was a constant process of radioactive decay of unstable atomic nuclei. As a result of this, the total radioactivity of the Earth's substance and rocks gradually decreased. Relatively short-lived isotopes decayed completely. Mainly elements with half-lives measured in billions of years have been preserved, as well as relatively short-lived secondary products of radioactive decay, forming successive chains of transformations, the so-called families of radioactive elements. In the earth's crust, natural radionuclides can be more or less evenly dispersed or concentrated in the form of deposits.
Natural (natural) radionuclides can be divided into three groups:
Radionuclides belonging to radioactive families (series),
Other (not belonging to radioactive families) radionuclides that became part of the earth's crust during the formation of the planet,
Radionuclides formed under the influence of cosmic radiation.
During the formation of the Earth, radionuclides, along with stable nuclides, also became part of its crust. Most of these radionuclides belong to the so-called radioactive families (series). Each series represents a chain of successive radioactive transformations, when the nucleus formed during the decay of the parent nucleus also, in turn, decays, again generating an unstable nucleus, etc. The beginning of such a chain is a radionuclide, which is not formed from another radionuclide, but is contained in the earth's crust and biosphere from the moment of their birth. This radionuclide is called the ancestor and the entire family (series) is named after it. In total, there are three ancestors in nature - uranium-235, uranium-238 and thorium-232, and, accordingly, three radioactive series - two uranium and thorium. All series end with stable isotopes of lead.
Most long period The half-life of thorium is 14 billion years, so it has been preserved almost completely since the accretion of the Earth. Uranium-238 decayed to a large extent, the vast majority of uranium-235 decayed, and the isotope neptunium-232 decayed entirely. For this reason, there is a lot of thorium in the earth's crust (almost 20 times more uranium), and uranium-235 is 140 times less than uranium-238. Since the ancestor of the fourth family (neptunium) has completely disintegrated since the accretion of the Earth, it is almost absent from rocks. Neptunium has been found in uranium ores in negligible quantities. But its origin is secondary and is due to the bombardment of uranium-238 nuclei by cosmic ray neutrons. Neptunium is now produced using artificial nuclear reactions. For an ecologist it is of no interest.
About 0.0003% (according to various sources 0.00025-0.0004%) of the earth's crust is uranium. That is, one cubic meter of the most ordinary soil contains an average of 5 grams of uranium. There are places where this amount is thousands of times greater - these are uranium deposits. In cubic meter sea water contains about 1.5 mg of uranium. This natural chemical element is represented by two isotopes -238U and 235U, each of which is the founder of its own radioactive series. The vast majority of natural uranium (99.3%) is uranium-238. This radionuclide is very stable, the probability of its decay (namely, alpha decay) is very small. This probability is characterized by a half-life of 4.5 billion years. That is, since the formation of our planet, its quantity has decreased by half. From this, in turn, it follows that the background radiation on our planet used to be higher. Chains of radioactive transformations that generate natural radionuclides of the uranium series:
The radioactive series includes both long-lived radionuclides (that is, radionuclides with a long half-life) and short-lived ones, but all radionuclides in the series exist in nature, even those that decay quickly. This is due to the fact that over time, an equilibrium has been established (the so-called “secular equilibrium”) - the decay rate of each radionuclide is equal to the rate of its formation.
There are natural radionuclides that entered the earth's crust during the formation of the planet and that do not belong to the uranium or thorium series. First of all, it is potassium-40. The content of 40 K in the earth's crust is about 0.00027% (mass), half-life is 1.3 billion years. The daughter nuclide, calcium-40, is stable. Potassium-40 is found in significant quantities in plants and living organisms and makes a significant contribution to the total dose of internal radiation to humans.
Natural potassium contains three isotopes: potassium-39, potassium-40 and potassium-41, of which only potassium-40 is radioactive. The quantitative ratio of these three isotopes in nature looks like this: 93.08%, 0.012% and 6.91%.
Potassium-40 breaks down in two ways. About 88% of its atoms experience beta radiation and become calcium-40 atoms. The remaining 12% of atoms, experiencing K-capture, turn into argon-40 atoms. The potassium-argon method for determining the absolute age of rocks and minerals is based on this property of potassium-40.
The third group of natural radionuclides consists of cosmogenic radionuclides. These radionuclides are formed under the influence of cosmic radiation from stable nuclides as a result of nuclear reactions. These include tritium, beryllium-7, carbon-14, sodium-22. For example, nuclear reactions of the formation of tritium and carbon-14 from nitrogen under the influence of cosmic neutrons:
Carbon occupies a special place among natural radioisotopes. Natural carbon consists of two stable isotopes, among which carbon-12 predominates (98.89%). The rest is almost entirely carbon-13 (1.11%).
In addition to the stable isotopes of carbon, five more radioactive ones are known. Four of them (carbon-10, carbon-11, carbon-15 and carbon-16) have very short half-lives (seconds and fractions of a second). A fifth radioisotope, carbon-14, has a half-life of 5,730 years.
In nature, the concentration of carbon-14 is extremely low. For example, in modern plants one atom of this isotope accounts for 10 9 atoms of carbon-12 and carbon-13. However, with the advent of atomic weapons and nuclear technology, carbon-14 is produced artificially by the interaction of slow neutrons with atmospheric nitrogen, so its quantity is constantly growing.
There is some convention regarding what background is considered “normal”. Thus, with the “planetary average” annual effective dose per person being 2.4 mSv, in many countries this value is 7-9 mSv/year. That is, from time immemorial, millions of people have lived under conditions of natural dose loads that are several times higher than the statistical average. Medical research and demographic statistics show that this does not affect their lives in any way and does not have any negative impact on their health or the health of their offspring.
Speaking about the conventionality of the concept of “normal” natural background, we can also point out a number of places on the planet where the level of natural radiation exceeds the statistical average not only several times, but also tens of times (table); tens and hundreds of thousands of inhabitants are exposed to this effect. And this is also the norm, this also does not affect their health in any way. Moreover, many areas with increased background radiation have been places of mass tourism (sea coasts) and recognized resorts (Caucasian coasts) for centuries. Mineral water, Karlovy Vary, etc.).
07.12.2016
Curiosity rover has on board a RAD device for determining the intensity of radioactive exposure. During its flight to Mars, Curiosity measured background radiation, and today scientists working with NASA spoke about these results. Since the rover was flying in a capsule, and the radiation sensor was located inside, these measurements practically correspond to the radiation background that will be present in a manned spacecraft.The RAD device consists of three silicon solid-state wafers that act as a detector. Additionally, it has a cesium iodide crystal, which is used as a scintillator. The RAD is mounted to look at the zenith during landing and capture a 65-degree field.
In fact, it is a radiation telescope that detects ionizing radiation and charged particles in a wide range.
The equivalent dose of absorbed radiation exposure is 2 times higher than the dose of the ISS.
A six-month flight to Mars is approximately equivalent to 1 year spent in low-Earth orbit. Considering that the total duration of the expedition should be about 500 days, the prospect is not optimistic.
For humans, accumulated radiation of 1 Sievert increases the risk of cancer by 5%. NASA allows its astronauts to accumulate no more than 3% risk or 0.6 Sievert over their careers.
The life expectancy of astronauts is lower than the average in their countries. At least a quarter of deaths are due to cancer.
Of the 112 Russian cosmonauts who flew, 28 are no longer with us. Five people died: Yuri Gagarin - on the fighter, Vladimir Komarov, Georgy Dobrovolsky, Vladislav Volkov and Viktor Patsayev - when returning from orbit to Earth. Vasily Lazarev died from poisoning with low-quality alcohol.
Of the 22 remaining conquerors of the star ocean, the cause of death for nine was oncology. Anatoly Levchenko (47 years old), Yuri Artyukhin (68), Lev Demin (72), Vladimir Vasyutin (50), Gennady Strekalov (64), Gennady Sarafanov (63), Konstantin Feoktistov (83), Vitaly Sevastyanov (75) died of cancer. ). The official cause of death for another astronaut who died of cancer has not been disclosed. The healthiest and strongest are selected for flights beyond the Earth.
So, nine out of 22 astronauts who died from cancer make up 40.9%. Now let's look at similar statistics for the country as a whole. Last year, 1 million 768 thousand 500 Russians left this world (Rosstat data). At the same time, 173.2 thousand died from external causes (transport emergencies, alcohol poisoning, suicides, murders). That leaves 1 million 595 thousand 300. How many citizens have been killed by oncology? Answer: 265.1 thousand people. Or 16.6%. Let's compare: 40.9 and 16.6%. It turns out that ordinary citizens die from cancer 2.5 times less often than astronauts.
There is no similar information on the US astronaut corps. But even fragmentary data indicate that oncology is also affecting American astronauts. Here is an incomplete list of victims of this terrible disease: John Swigert Jr. - bone marrow cancer, Donald Slayton - brain cancer, Charles Veach - brain cancer, David Walker - cancer, Alan Shepard - leukemia, George Lowe - colon cancer, Ronald Paris - brain tumor brain
During one flight into Earth orbit, each crew member receives the same amount of radiation as if they had been examined in an X-ray room 150–400 times.
Taking into account that the daily dose on the ISS is up to 1 mSv (the annual permissible dose for humans on earth), the maximum period for astronauts to stay in orbit is limited to approximately 600 days over the entire career.
On Mars itself, radiation should be approximately two times lower than in space, due to the atmosphere and dust suspension in it, i.e., correspond to the level of the ISS, but exact indicators have not yet been published. RAD indicators during the days of dust storms will be interesting - we will find out how good Martian dust is as a radiation shield.
Now the record for staying in near-Earth orbit belongs to 55-year-old Sergei Krikalev - he has 803 days. But he collected them intermittently - in total he made 6 flights from 1988 to 2005.
Radiation in space comes primarily from two sources: from the Sun, during flares and coronal ejections, and from cosmic rays, which occur during supernova explosions or other high-energy events in our and other galaxies.
In the illustration: the interaction of the solar “wind” and the Earth’s magnetosphere.
Cosmic rays make up the bulk of radiation during interplanetary travel. They account for a share of radiation of 1.8 mSv per day. Only three percent of the radiation accumulated by Curiosity from the Sun. This is also due to the fact that the flight took place at a relatively calm time. Outbreaks increase the total dose, and it approaches 2 mSv per day.
Peaks occur during solar flares.
Current technical means are more effective against solar radiation, which has low energy. For example, you can equip a protective capsule where astronauts can hide during solar flares. However, even 30 cm aluminum walls will not protect from interstellar cosmic rays. Lead ones would probably help better, but this would significantly increase the mass of the ship, which means the cost of launching and accelerating it.
It may be necessary to assemble an interplanetary spacecraft in orbit around the Earth - hanging heavy lead plates to protect against radiation. Or use the Moon for assembly, where the weight of the spacecraft will be lower.
Most effective means To minimize radiation exposure, new types of engines should be developed that will significantly reduce the flight time to Mars and back. NASA is currently working on solar electric propulsion and nuclear thermal propulsion. The first can, in theory, accelerate up to 20 times faster than modern chemical engines, but acceleration will be very long due to low thrust. A device with such an engine is supposed to be sent to tow an asteroid, which NASA wants to capture and transfer to lunar orbit for subsequent visit by astronauts.
The most promising and encouraging developments in electric propulsion are being carried out under the VASIMR project. But to travel to Mars, solar panels will not be enough - you will need a reactor.
A nuclear thermal engine develops a specific impulse approximately three times higher modern types rockets. Its essence is simple: the reactor heats the working gas (presumably hydrogen) to high temperatures without the use of an oxidizer, which is required by chemical rockets. In this case, the heating temperature limit is determined only by the material from which the engine itself is made.
But such simplicity also causes difficulties - the thrust is very difficult to control. NASA is trying to solve this problem, but does not consider the development of nuclear powered engines a priority.
The use of a nuclear reactor is still promising in that part of the energy could be used for generation electromagnetic field, which would additionally protect pilots from both cosmic radiation and radiation from its own reactor. The same technology would make it profitable to extract water from the Moon or asteroids, that is, it would further stimulate the commercial use of space.
Although now this is nothing more than theoretical reasoning, it is possible that such a scheme will become the key to a new level of exploration of the Solar system.
Additional requirements for space and military microcircuits.
First of all, there are increased requirements for reliability (both of the crystal itself and the case), resistance to vibration and overload, humidity, the temperature range is significantly wider, since military equipment must work both at -40C and when heated to 100C .
Then - resistance to the damaging factors of a nuclear explosion - EMP, a large instantaneous dose of gamma / neutron radiation. Normal operation may not be possible at the time of the explosion, but at least the device should not be irreversibly damaged.
And finally - if the microcircuit is for space - stability of parameters as the total radiation dose slowly increases and survival after an encounter with heavily charged particles of cosmic radiation.
How does radiation affect microcircuits?
In “pieces of particles”, cosmic radiation consists of 90% protons (i.e. hydrogen ions), 7% helium nuclei (alpha particles), ~1% heavier atoms and ~1% electrons. Well, stars (including the Sun), galactic nuclei, Milky Way- abundantly illuminate everything not only with visible light, but also with x-ray and gamma radiation. During solar flares, radiation from the sun increases 1000-1000000 times, which can be a serious problem (both for people of the future and present spacecraft outside the earth's magnetosphere).
There are no neutrons in cosmic radiation for an obvious reason - free neutrons have a half-life of 611 seconds, and turn into protons. A neutron cannot even reach a neutron from the sun, except at a very relativistic speed. A small number of neutrons arrive from the earth, but these are minor things.
There are 2 belts of charged particles around the earth - the so-called radiation ones: at an altitude of ~4000 km from protons, and at an altitude of ~17000 km from electrons. Particles there move in closed orbits, captured by the earth's magnetic field. There is also a Brazilian magnetic anomaly - where the inner radiation belt comes closer to the earth, up to an altitude of 200 km.
Electrons, gamma and x-rays.
When gamma and X-ray radiation (including secondary radiation obtained due to the collision of electrons with the body of the device) passes through the microcircuit, a charge begins to gradually accumulate in the gate dielectric of the transistors, and accordingly, the parameters of the transistors begin to slowly change - the threshold voltage of the transistors and the leakage current. An ordinary civilian digital microcircuit may stop working normally after 5000 rads (however, a person can stop working after 500-1000 rads).
In addition, gamma and x-ray radiation causes all pn junctions inside the chip to act like small " solar panels“- and if in space the radiation is usually insufficient to greatly affect the operation of the microcircuit, during a nuclear explosion the flow of gamma and x-ray radiation may already be sufficient to disrupt the operation of the microcircuit due to the photoelectric effect.
In a low orbit of 300-500 km (where people fly), the annual dose can be 100 rads or less, so even over 10 years the accumulated dose will be tolerated by civilian microcircuits. But in high orbits >1000km the annual dose can be 10,000-20,000 rad, and conventional microcircuits will accumulate a lethal dose in a matter of months.
Heavy charged particles (HCP) - protons, alpha particles and high-energy ions
This is the biggest problem in space electronics - high energy charge chargers have such high energy that they “pierce” the microcircuit through (together with the satellite body), and leave a “trail” of charge behind them. IN best case scenario this can lead to a software error (0 becomes 1 or vice versa - single-event upset, SEU), at worst - lead to a thyristor latchup (single-event latchup, SEL). In a latched chip, the power supply is short-circuited to ground, the current can flow very high and lead to the combustion of the microcircuit. If you manage to turn off the power and connect it before combustion, then everything will work as usual.
Perhaps this is exactly what happened with Phobos-Grunt - according to official version non-radiation-resistant imported memory chips failed already on the second orbit, and this is only possible due to the high-voltage radiation (judging by the total accumulated dose of radiation in low orbit, a civilian chip could work for a long time).
It is latching that limits the use of conventional ground-based chips in space with all sorts of software tricks to increase reliability.
What happens if you protect a spacecraft with lead?
Particles with an energy of 3*1020 eV sometimes arrive to us with galactic cosmic rays, i.e. 300,000,000 TeV. In human-understandable units, this is about 50J, i.e. one elementary particle energy like a bullet from a small-caliber sports pistol.
When such a particle collides, for example, with a radiation shield lead atom, it simply tears it to shreds. The fragments will also have gigantic energy, and will also tear everything in their path to shreds. Ultimately, the thicker the protection from heavy elements, the more fragments and secondary radiation we will receive. Lead can greatly weaken only the relatively mild radiation of terrestrial planets. nuclear reactors.
High-energy gamma radiation has a similar effect - it is also capable of tearing heavy atoms to shreds due to the photonuclear reaction.
The processes taking place can be considered using an X-ray tube as an example.
Electrons from the cathode fly towards the anode from heavy metal, and upon collision with it, X-ray radiation is generated due to bremsstrahlung.
When an electron from cosmic radiation arrives at our ship, our radiation protection will turn into a natural X-ray tube, next to our delicate microcircuits and even more delicate living organisms.
Because of all these problems, radiation protection made from heavy elements, like on earth, is not used in space. They use protection mostly consisting of aluminum, hydrogen (from various polyethylenes, etc.), since it can only be broken down into subatomic particles - and this is much more difficult, and such protection generates less secondary radiation.
But in any case, there is no protection from high-energy particles, moreover, the more protection, the more secondary radiation from high-energy particles, optimal thickness it turns out about 2-3mm aluminum. The most difficult thing is a combination of hydrogen protection and slightly heavier elements (the so-called Graded-Z) - but this is not much better than pure “hydrogen” protection. In general, cosmic radiation can be attenuated by about 10 times, and that's all.
As already mentioned, as soon as the Americans began their space program, their scientist James Van Allen has done enough 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 established 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. On this occasion, Van Allen wrote: “Radiation belts can be compared to a leaky vessel, which is constantly replenished from the Sun and flows 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?
Orbits of atmospheric particles in the exosphere(dic.academic.ru)
The Moon does not have Van Allen belts. She also has no protective atmosphere. It is open to all solar winds. If a strong solar flare had occurred during the lunar expedition, a colossal flow of radiation would have incinerated both the capsules and the astronauts on the part of the lunar surface where they spent their day. This radiation is not just dangerous - it is deadly!
In 1963, Soviet scientists told renowned British astronomer Bernard Lovell that they did not know of a way to protect astronauts from the deadly effects of cosmic radiation. This meant that even the much thicker metal shells of the Russian devices could not cope with the radiation. How could the thinnest (almost like foil) metal used in American capsules protect astronauts? NASA knew this was impossible. The space monkeys died less than 10 days after returning, but NASA never told us the real reason their death.
Monkey-astronaut (RGANT archive)
Most people, even those knowledgeable in space, are not aware of the existence of deadly radiation permeating its expanses. Oddly enough (or perhaps just for reasons that can be guessed), in the American “Illustrated Encyclopedia of Space Technology” the phrase “cosmic radiation” does not appear even once. And in general, American researchers (especially those associated with NASA) avoid this topic a mile away.
Meanwhile, Lovell, after talking with Russian colleagues who were well aware of cosmic radiation, sent the information he had to NASA administrator Hugh Dryden, but he ignored it.
One of the astronauts who allegedly visited the Moon, Collins, mentioned cosmic radiation only twice in his book:
"At least the Moon was well beyond Earth's Van Allen belts, which meant a good dose of radiation for those who went there and a lethal dose for those who lingered."
“Thus, the Van Allen radiation belts surrounding the Earth and the possibility of solar flares require understanding and preparation to avoid exposing the crew to increased doses of radiation.”
So what does “understand and prepare” mean? Does this mean that beyond the Van Allen belts, the rest of space is free of radiation? Or did NASA have a secret strategy for sheltering from solar flares after making the final decision on the expedition?
NASA claimed that it could simply predict solar flares, and therefore sent astronauts to the Moon when flares were not expected and the radiation danger to them was minimal.
While Armstrong and Aldrin were doing work in outer space
on the surface of the moon, Michael Collins
placed in orbit (NASA archive)
However, other experts say: “It is only possible to predict the approximate date of future maximum radiation and its density.”
The Soviet cosmonaut Leonov nevertheless went into outer space in 1966 - however, in a super-heavy lead suit. But after just three years American astronauts jumped on the surface of the Moon, and not at all in super-heavy spacesuits, but rather quite the opposite! Maybe over the years, experts from NASA have managed to find some kind of ultra-light material that reliably protects against radiation?
However, researchers suddenly find out that at least Apollo 10, Apollo 11 and Apollo 12 set off precisely during those periods when the number of sunspots and the corresponding solar activity were approaching a maximum. The generally accepted theoretical maximum of solar cycle 20 lasted from December 1968 to December 1969. During this period, the Apollo 8, Apollo 9, Apollo 10, Apollo 11, and Apollo 12 missions supposedly moved beyond the protection zone of the Van Allen belts and entered cislunar space.
Further study of monthly graphs showed that single solar flares are a random phenomenon, occurring spontaneously over an 11-year cycle. It also happens that during the “low” period of the cycle a large number of outbreaks occur in a short period of time, and during the “high” period - a very small number. But what is important is that very strong outbreaks can occur at any time in the cycle.
During the Apollo era, American astronauts spent a total of almost 90 days in space. Since radiation from unpredictable solar flares reaches the Earth or Moon in less than 15 minutes, the only way to protect against it would be to use lead containers. But if the rocket’s power was enough to lift such an extra weight, then why was it necessary to go into space in tiny capsules (literally 0.1 mm of aluminum) at a pressure of 0.34 atmospheres?
This despite the fact that even thin layer protective coating, called “mylar,” according to the Apollo 11 crew, turned out to be so heavy that it had to be urgently erased from the lunar module!
It seems that NASA selected special guys for lunar expeditions, albeit adjusted for circumstances, cast not from steel, but from lead. The American researcher of the problem, Ralph Rene, was not too lazy to calculate how often each of the supposedly lunar expeditions must have been affected by solar activity.
By the way, one of the authoritative employees of NASA (distinguished physicist, by the way) Bill Modlin, in his work “Prospects for Interstellar Travel,” frankly reported: “Solar flares can emit GeV protons in the same energy range as most cosmic particles, but much more intense . The increase in their energy with increased radiation poses a particular danger, since GeV protons penetrate several meters of material... Solar (or stellar) flares with the emission of protons are a periodically occurring very serious danger in interplanetary space, which provides a radiation dose of hundreds of thousands of roentgens in a few hours at the distance from the Sun to the Earth. This dose is lethal and millions of times higher than permissible. Death can occur after 500 roentgens in a short period of time.”
Yes, the brave American guys then had to shine worse than the fourth Chernobyl power unit. “Cosmic particles are dangerous, they come from all directions and require a minimum of two meters of dense shielding around any living organisms.” But the space capsules that NASA demonstrates to this day were just over 4 m in diameter. With the thickness of the walls recommended by Modlin, the astronauts, even without any equipment, would not have fit into them, not to mention the fact that there would not have been enough fuel to lift such capsules. But, obviously, neither the leadership of NASA nor the astronauts they sent to the Moon read their colleague’s books and, being blissfully unaware, overcame all the thorns on the road to the stars.
However, maybe NASA actually developed some kind of ultra-reliable spacesuits for them, using (obviously, very secret) ultra-light material that protects against radiation? But why wasn’t it used anywhere else, as they say, for peaceful purposes? Well, okay, they didn’t want to help the USSR with Chernobyl: after all, perestroika had not yet begun. But, for example, in 1979 in the same USA at the Three Mile Island nuclear power plant there was a major accident reactor unit, which led to a meltdown of the reactor core. So why didn’t the American liquidators use space suits based on the much-advertised NASA technology, costing no less than $7 million, to eliminate this atomic time bomb on their territory?..
Who hasn’t dreamed of flying into space, even knowing what cosmic radiation is? At least fly to Earth orbit or to the Moon, or even better - further away, to some Orion. In fact, the human body is very little adapted to such travel. Even when flying into orbit, astronauts face many dangers that threaten their health and sometimes their lives. Everyone watched the cult TV series Star Trek. One of the wonderful characters there gave a very accurate description of the phenomenon of cosmic radiation. “It's danger and disease in darkness and silence,” said Leonard McCoy, aka Bony, aka Bonesetter. It is very difficult to be more precise. Cosmic radiation during travel will make a person tired, weak, sick, and suffering from depression.
Feelings in flight
The human body is not adapted to life in airless space, since evolution did not include such abilities in its arsenal. Books have been written about this, this issue is studied in detail by medicine, centers have been created all over the world to study the problems of medicine in space, in extreme conditions, at high altitudes. Of course, it’s funny to watch an astronaut smile on the screen while they float in the air various items. In fact, his expedition is much more serious and fraught with consequences than it seems to an ordinary inhabitant from Earth, and it is not only cosmic radiation that creates trouble.
At the request of journalists, astronauts, engineers, scientists, who have experienced first-hand everything that happens to a person in space, spoke about the sequence of various new sensations in an artificially created environment alien to the body. Literally ten seconds after the start of the flight, an unprepared person loses consciousness because the acceleration of the spacecraft increases, separating it from the launch complex. A person does not yet feel cosmic rays as strongly as in outer space - the radiation is absorbed by the atmosphere of our planet.
Major troubles
But there are also enough overloads: a person becomes four times heavier than his own weight, he is literally pressed into a chair, it is difficult to even move his arm. Everyone has seen these special chairs, for example, in the Soyuz spacecraft. But not everyone understood why the astronaut had such a strange pose. However, it is necessary because overloads send almost all the blood in the body down to the legs, and the brain is left without blood supply, which is why fainting occurs. But a chair invented in the Soviet Union helps to avoid at least this trouble: the position with raised legs forces the blood to supply oxygen to all parts of the brain.
Ten minutes after the start of the flight, the lack of gravity will cause a person to almost lose their sense of balance, orientation and coordination in space; a person may not even be able to track moving objects. He feels nauseous and vomits. Cosmic rays can cause the same thing - the radiation here is already much stronger, and if there is a plasma ejection into the sun, the threat to the lives of astronauts in orbit is real, even airline passengers can suffer in flight at high altitude. Vision changes, swelling and changes occur in the retina of the eyes, and the eyeball becomes deformed. A person becomes weak and cannot complete the tasks that are assigned to him.
Puzzles
However, from time to time people also feel high cosmic radiation on Earth; for this they do not necessarily have to travel into outer space. Our planet is constantly bombarded by rays of cosmic origin, and scientists suggest that our atmosphere does not always provide sufficient protection. There are many theories that give these energetic particles a power that greatly limits the chances of planets having life on them. In many ways, the nature of these cosmic rays is still an insoluble mystery for our scientists.
Subatomic charged particles in space move almost at the speed of light, they have already been recorded several times on satellites, and even on These nuclei chemical elements, protons, electrons, photons and neutrinos. It is also possible that particles - heavy and superheavy - may be present in the attack of cosmic radiation. If they could be discovered, a number of contradictions in cosmological and astronomical observations would be resolved.
Atmosphere
What protects us from cosmic radiation? Only our atmosphere. Cosmic rays, threatening the death of all living things, collide in it and generate streams of other particles - harmless, including muons, much heavier relatives of electrons. A potential danger still exists, since some particles reach the Earth's surface and penetrate many tens of meters into its depths. The level of radiation that any planet receives indicates its suitability or unsuitability for life. The high energy that cosmic rays carry with them far exceeds the radiation from its own star, because the energy of protons and photons, for example, of our Sun, is lower.
And with high life is impossible. On Earth, this dose is controlled by the strength of the planet’s magnetic field and the thickness of the atmosphere; they significantly reduce the danger of cosmic radiation. For example, there could well be life on Mars, but the atmosphere there is negligible, there is no magnetic field of its own, and therefore there is no protection from cosmic rays that penetrate the entire space. The level of radiation on Mars is enormous. And the influence of cosmic radiation on the planet’s biosphere is such that all life on it dies.
What's more important?
We are lucky, we have both a thick atmosphere enveloping the Earth and our own fairly powerful magnetic field that absorbs harmful particles that reach the earth’s crust. I wonder whose protection for the planet works more actively - the atmosphere or the magnetic field? Researchers are experimenting by creating models of planets, either providing them with a magnetic field or not. And the magnetic field itself differs in strength between these models of planets. Previously, scientists were sure that it was the main protection against cosmic radiation, since they controlled its level on the surface. However, it was discovered that the amount of radiation is determined to a greater extent by the thickness of the atmosphere that covers the planet.
If the magnetic field on Earth is “turned off,” the radiation dose will only double. This is a lot, but even for us it will have a rather insignificant effect. And if you leave the magnetic field and remove the atmosphere to one tenth of its total amount, then the dose will increase deadly - by two orders of magnitude. Terrible cosmic radiation will kill everything and everyone on Earth. Our Sun is a yellow dwarf star, and it is around them that the planets are considered the main contenders for habitability. These stars are relatively dim, there are many of them, about eighty percent of the total number of stars in our Universe.
Space and evolution
Theorists have calculated that such planets orbiting yellow dwarfs, which are in zones suitable for life, have much weaker magnetic fields. This is especially true for the so-called super-Earths - large rocky planets with a mass ten times greater than our Earth. Astrobiologists were confident that weak magnetic fields significantly reduced the chances of habitability. And now new discoveries suggest that this is not so big problem, as we used to think. The main thing would be the atmosphere.
Scientists are comprehensively studying the effect of increasing radiation on existing living organisms - animals, as well as on a variety of plants. Radiation-related research involves exposing them to varying degrees of radiation, from low to extreme levels, and then determining whether they will survive and how differently they will feel if they do. Microorganisms affected by gradually increasing radiation may show us how evolution took place on Earth. It was cosmic rays and their high radiation that once forced the future man to get off the palm tree and study space. And humanity will never return to the trees again.
Cosmic radiation 2017
At the beginning of September 2017, our entire planet was greatly alarmed. The sun suddenly ejected tons of solar material after the merger of two large groups dark spots. And this emission was accompanied by X-class flares, which forced the planet’s magnetic field to literally wear out. A large magnetic storm followed, causing illness in many people, as well as extremely rare, almost unprecedented natural phenomena on Earth. For example, near Moscow and Novosibirsk, powerful images of the northern lights were recorded that had never been seen in these latitudes. However, the beauty of such phenomena did not obscure the consequences of a deadly solar flare that permeated the planet with cosmic radiation, which turned out to be truly dangerous.
Its power was close to the maximum, X-9.3, where the letter is the class (extremely large flash), and the number is the flash strength (out of ten possible). Along with this emission, there was a threat of failure of space communication systems and all equipment on board. The astronauts were forced to wait out this stream of terrible cosmic radiation carried by cosmic rays in a special shelter. The quality of communications during these two days deteriorated significantly in both Europe and America, precisely where the flow of charged particles from space was directed. About a day before the particles reached the Earth's surface, a warning was issued about cosmic radiation, which sounded on every continent and in every country.
Power of the Sun
The energy emitted by our star into the surrounding space is truly enormous. Within a few minutes, many billions of megatons, if calculated in TNT equivalent, fly into space. Humanity will be able to produce so much energy at current rates only in a million years. Just a fifth of the total energy emitted by the Sun per second. And this is our small and not too hot dwarf! If you just imagine how much destructive energy other sources of cosmic radiation produce, next to which our Sun will seem like an almost invisible grain of sand, your head will spin. What a blessing that we have a good magnetic field and an excellent atmosphere that prevent us from dying!
People are exposed to such danger every day, since radioactive radiation in space never runs out. It is from there that most of the radiation comes to us - from black holes and from clusters of stars. It is capable of killing with a large dose of radiation, and with a small dose it can turn us into mutants. However, we must also remember that evolution on Earth occurred thanks to such flows; radiation changed the structure of DNA to the state that we see today. If we go through this “medicine”, that is, if the radiation emitted by stars exceeds permissible levels, the processes will be irreversible. After all, if creatures mutate, they will no longer return to their original state, there is no reverse effect. Therefore, we will never again see those living organisms that were present in the newborn life on Earth. Any organism tries to adapt to changes occurring in environment. Either he dies or he adapts. But there is no turning back.
ISS and solar flare
When the Sun sent us its greeting with a stream of charged particles, the ISS was just passing between the Earth and the star. The high-energy protons released during the explosion created a completely undesirable background radiation within the station. These particles penetrate through absolutely any spaceship. Nevertheless, space technology this radiation was spared as the impact was powerful but too short to incapacitate her. However, the crew was hiding in a special shelter all this time, because the human body is much more vulnerable than modern technology. There was not just one flare, they came in a whole series, and it all started on September 4, 2017, in order to shake the cosmos with an extreme emission on September 6. Over the past twelve years, a stronger flow has not yet been observed on Earth. The cloud of plasma that was ejected by the Sun overtook the Earth much earlier than planned, which means that the speed and power of the flow exceeded the expected one and a half times. Accordingly, the impact on the Earth was much stronger than expected. The cloud was twelve hours ahead of all the calculations of our scientists, and accordingly more disturbed the planet’s magnetic field.
The power of the magnetic storm turned out to be four out of five possible, that is, ten times more than expected. In Canada, auroras were also observed even in mid-latitudes, as in Russia. A planetary magnetic storm occurred on Earth. You can imagine what was going on there in space! Radiation is the most significant danger of all existing there. Protection from it is needed immediately, as soon as the spacecraft leaves the upper atmosphere and leaves magnetic fields far below. Streams of uncharged and charged particles - radiation - constantly permeate space. The same conditions await us on any planet in the solar system: there is no magnetic field or atmosphere on our planets.
Types of radiation
In space, ionizing radiation is considered the most dangerous. These are gamma radiation and X-rays from the Sun, these are particles flying after chromospheric solar flares, these are extragalactic, galactic and solar cosmic rays, solar wind, protons and electrons of radiation belts, alpha particles and neutrons. There is also non-ionizing radiation - ultraviolet and infrared radiation from the Sun, this is electromagnetic radiation and visible light. There is no great danger in them. We are protected by the atmosphere, and the astronaut is protected by a space suit and the skin of the ship.
Ionizing radiation causes irreparable harm. This is a harmful effect on everything life processes that occur in the human body. When a high-energy particle or photon passes through a substance in its path, it forms a pair of charged particles called an ion as a result of interaction with this substance. This affects even nonliving matter, and living matter reacts most violently, since the organization of highly specialized cells requires renewal, and this process occurs dynamically as long as the organism is alive. And the higher the level of evolutionary development of the organism, the more irreversible the radiation damage becomes.
Radiation protection
Scientists are looking for such tools in a variety of areas modern science, including in pharmacology. So far, no drug has produced effective results, and people exposed to radiation continue to die. Experiments are carried out on animals both on earth and in space. The only thing that became clear was that any drug should be taken by a person before the start of radiation, and not after.
And if we take into account that all such drugs are toxic, then we can assume that the fight against the effects of radiation has not yet led to a single victory. Even if taken on time, pharmacological agents provide protection only against gamma radiation and X-rays, but do not protect against ionizing radiation from protons, alpha particles and fast neutrons.
Cosmic radiation represents big problem for spacecraft designers. They strive to protect astronauts from it, who will be on the surface of the Moon or go on long journeys into the depths of the Universe. If the necessary protection is not provided, these particles, flying at great speed, will penetrate the astronaut's body and damage his DNA, which can increase the risk of cancer. Unfortunately, so far all known methods of protection are either ineffective or impracticable.
Materials traditionally used to build spacecraft, such as aluminum, trap some space particles, but long-term missions in space require stronger protection.
The US Aerospace Agency (NASA) willingly takes on the most extravagant, at first glance, ideas. After all, no one can predict for sure which of them will one day turn into a serious breakthrough in space research. The agency has a special institute for advanced concepts (NASA Institute for Advanced Concepts - NIAC), designed to accumulate just such developments - for a very long term. Through this institute, NASA distributes grants to various universities and institutes for the development of “brilliant madness.”
The following options are currently being explored:
Protection with certain materials. Some materials, such as water or polypropylene, have good protective properties. But in order to protect a spaceship with them, a lot of them will be needed, and the weight of the ship will become unacceptably large.
Currently, NASA employees have developed a new ultra-strong material, related to polyethylene, which they are going to use in assembly spaceships future. “Space plastic” will be able to protect astronauts from cosmic radiation better than metal shields, but is much lighter than known metals. Experts are convinced that when the material is given sufficient heat resistance, it will even be possible to make the skin of spacecraft from it.
Previously, it was believed that only an all-metal shell would allow a manned spacecraft to pass through the Earth's radiation belts - streams of charged particles held by the magnetic field near the planet. This was not encountered during flights to the ISS, since the station’s orbit passes noticeably below the dangerous area. In addition, astronauts are threatened by solar flares - a source of gamma and X-rays, and parts of the ship itself are capable of secondary radiation - due to the decay of radioisotopes formed during the “first encounter” with radiation.
Now scientists believe that the new RXF1 plastic copes better with these problems, and its low density is not the last argument in its favor: the rockets’ carrying capacity is still not high enough. The results of laboratory tests in which it was compared with aluminum are known: RXF1 can withstand three times greater loads at three times lower density and traps more high-energy particles. The polymer has not yet been patented, so the method of its manufacture has not been reported. Lenta.ru reports this with reference to science.nasa.gov.
Inflatable structures. The inflatable module, made of especially durable RXF1 plastic, will not only be more compact at launch, but also lighter than a solid steel structure. Of course, its developers will need to provide sufficient reliable protection from micrometeorites coupled with “space debris”, but there is nothing fundamentally impossible about this.
Something is already there - the private inflatable unmanned ship Genesis II is already in orbit. Launched in 2007 by the Russian Dnepr rocket. Moreover, its weight is quite impressive for a device created by a private company - over 1300 kg.
CSS (Commercial Space Station) Skywalker - commercial inflatable project orbital station. NASA is allocating about $4 billion to support the project for 20110-2013. We are talking about the development of new technologies for inflatable modules for the exploration of space and the celestial bodies of the Solar System.
It is not known how much the inflatable structure will cost. But the total costs for the development of new technologies have already been announced. In 2011, $652 million will be allocated for these purposes, in 2012 (if the budget is not revised again) - $1262 million, in 2013 - $1808 million. Research costs are planned to be steadily increased, but taking into account sad experience“Constellations” that missed the deadlines and budgets, without focusing on one large-scale program.
Inflatable modules, automatic devices for docking vehicles, in-orbit fuel storage systems, autonomous life support modules and complexes that provide landing on other celestial bodies. This is only a small part of the tasks that NASA is now facing to solve the problem of landing a man on the Moon.
Magnetic and electrostatic protection. Powerful magnets can be used to repel flying particles, but magnets are very heavy, and it is not yet known how dangerous a magnetic field strong enough to reflect cosmic radiation would be for astronauts.
A spacecraft or station on the lunar surface with magnetic protection. A toroidal superconducting magnet with field strength will not allow most of the cosmic rays to penetrate into the cockpit located inside the magnet, and thereby reduce the total radiation doses from cosmic radiation by tens or more times.
Promising NASA projects are an electrostatic radiation shield for a lunar base and a lunar telescope with a liquid mirror (illustrations from spaceflightnow.com).
Biomedical solutions. The human body is capable of correcting DNA damage caused by small doses of radiation. If this ability is enhanced, astronauts will be able to withstand prolonged exposure to cosmic radiation. More details
Liquid hydrogen protection. NASA is considering the possibility of using spacecraft fuel tanks containing liquid hydrogen, which can be placed around the crew compartment, as protection against cosmic radiation. This idea is based on the fact that cosmic radiation loses energy when it collides with protons of other atoms. Since a hydrogen atom has only one proton in its nucleus, a proton from each of its nuclei "brakes" radiation. In elements with heavier nuclei, some protons block others, so cosmic rays do not reach them. Hydrogen protection can be provided, but it is not sufficient to prevent the risks of cancer.
Biosuit. This Bio-Suit project is being developed by a group of professors and students at the Massachusetts Institute of Technology (MIT). “Bio” - in this case, does not mean biotechnology, but lightness, unusual comfort for spacesuits, and in some cases even the imperceptibility of the shell, which is like a continuation of the body.
Instead of sewing and gluing a spacesuit from separate pieces of different fabrics, it will be sprayed directly onto a person's skin in the form of a quickly hardening spray. True, the helmet, gloves and boots will still remain traditional.
The technology of such spraying (a special polymer is used as a material) is already being tested by the American military. This process is called Electrospinlacing, it is being developed by specialists from the US Army research center - Soldier systems center, Natick.
To put it simply, we can say that the smallest droplets or short fibers of the polymer acquire an electrical charge and, under the influence of electrostatic field rush to their goal - the object that needs to be covered with film - where they form a fused surface. Scientists from MIT intend to create something similar, but capable of creating a moisture- and air-tight film on the body of a living person. After hardening, the film acquires high strength, maintaining elasticity sufficient for the movement of arms and legs.
It should be added that the project provides for an option when several different layers will be sprayed onto the body in a similar way, alternating with a variety of built-in electronics.
The development line of spacesuits as imagined by MIT scientists (illustration from the website mvl.mit.edu).
And the inventors of the biosuit talk about the promising self-tightening of polymer films in case of minor damage.
Even Professor Dava Newman herself cannot predict when this will become possible. Maybe in ten years, maybe in fifty.
But if you don’t start moving towards this result now, the “fantastic future” will not come.