Location without exposure to sunlight. The effect of solar radiation on humans

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Pregnant women and children under two years of age should not be exposed to the sun for more than 10-15 minutes a day.

In recent “hot years” we are constantly being scared by the sun: that ultraviolet is dangerous, that the skin ages faster under the influence of sunlight, that for this reason even skin cancer is possible ... But we are not afraid. During the winter, autumn and spring, the gloomy gray sky and the boring gray faces of the townspeople are so annoying that with the onset of summer, many, especially young people, use every opportunity to tan and “be like a chocolate bar”. Although if you listen to the doctors, there is harm from the sun, and considerable. But there are also benefits. Dermatologist Yuri SMIRNOV will help us choose the golden mean.

Sunburn is a darkening of the skin that occurs as a result of excessive formation of melanin pigment in its outer layer (epidermis) under the influence of ultraviolet rays of the sun or artificial light sources (mercury-quartz lamps, etc.), - explains Yuri Viktorovich. - And, by the way, as a rule, this indicates good tolerance and beneficial effects on the body of ultraviolet rays. And under their influence, biologically active substances are formed in the body, stimulating the activity of the nervous and endocrine systems, improving metabolism, resistance to infectious and other diseases. In addition, under the influence of ultraviolet radiation, as is known, vitamin D is formed, which promotes the absorption of calcium from the intestines, which is necessary for the skeletal system (and rickets develops with a lack of vitamin D). This vitamin ensures the normal activity of many enzymes.

But ultraviolet rays are harmful to our skin - everyone, including dermatologists, says so now. It is even known that only in people with very dark or black skin, a sufficient amount of melanin is secreted in the body, which allows them to protect themselves from the evil southern rays. Is not it?

The damage that can be done to our skin is directly proportional to the amount of time we spend in the sun. In small doses (up to 10 minutes), the sun only slightly irritates the skin, causing slight redness. At high doses, it becomes inflamed, swells. If radiation is continued, the skin may burn, causing it to blister and peel off. Excessive exposure to the sun damages the skin so much that it is no longer able to perform its protective functions. With severe burns, thermoregulation stops, which, in turn, leads to sunstroke. But 10-15 minutes in the sun a day will not hurt the skin at all. It is important to know the measure.

The danger of prolonged exposure to the sun lies also in the fact that under the influence of sunlight the skin loses its elasticity, smoothness and becomes covered with wrinkles. Unfortunately, nothing can slow down or stop this process. The biggest reason to avoid sun exposure is that the sun's rays cause severe changes in the skin that can lead to skin cancer. But you need to be under direct (precisely under direct when the sun is at its zenith!) rays of the sun for a very long time in order for such changes to occur.

- To whom the sun is generally contraindicated?

People with vitiligo (skin lacking pigmentation) or chloasma (skin areas with excessive pigmentation) should avoid sun exposure. In the first case, the skin burns quickly, in the second - the spots darken, become even more noticeable. With dermatitis, one should also not be in the sun: already dehydrated skin areas are even more dried out, which worsens its condition.

Sunbathing, however, can help those who suffer from acne. One way to clean the mouth of the sebaceous gland is to cause slight peeling of the skin. This method underlies the treatment with ultraviolet rays. Exposure to natural sunlight produces the same effect. When peeling, along with dead cells, scales that clog the mouth of the sebaceous gland come off the surface of the skin, and its functions are restored. Psoriasis is another skin condition that can benefit from sunbathing.

I heard that pregnant women generally better not stick out in the sun. And where then will her future baby get vitamin D, which is so necessary for bone formation?

Pregnant women, as well as the elderly, babies under two years old and people suffering from chronic lung diseases (especially tuberculosis), cardiovascular diseases, neurasthenia, lupus erythematosus, it is contraindicated to stay in the sun for a long time. In a good way, they should agree on the mode of exposure to the sun with a doctor.

Increased sensitivity to sunlight can also develop in people with impaired liver function as a result of diseases, alcohol abuse. In general, people with increased sensitivity to the sun's rays on the street should keep to the shady side, wear clothes made of light, light-colored fabrics with sleeves, lubricate exposed skin with sunscreen, and use a light-colored umbrella and goggles.

Unfortunately, even knowing that the sun is bad for the skin, many actively tan, believing that tanning will make them more attractive.

You need to sunbathe gradually. The first day in direct sunlight should be no more than 10-15 minutes, and residents of areas with a temperate climate, and even more so northerners vacationing in the south or in the mountains, the first days it is better not to sunbathe at all, but to be under an umbrella. With good tolerance, every day you can slightly increase your exposure to the sun by 5-10 minutes. The maximum period for an already tanned person should not exceed 1-2 hours. A beautiful even tan is obtained by lubricating the skin with clove, nut, peach or other vegetable oil before a sunbath.

The most favorable time for sunbathing in the southern strip- until 11-12 o'clock (morning hours), in the middle and northern - from 11 to 13 o'clock. When sunbathing, the head must be covered with a scarf, panama or hat. It is better to wear dark glasses: under the influence of direct sunlight in the mucous membrane of the eyes, which does not have a protective stratum corneum, inflammation may occur - conjunctivitis.

You can not sunbathe immediately after eating and on an empty stomach.

It is extremely harmful to sleep in the sun. Excessive exposure, the desire to tan as quickly as possible, in addition to general painful phenomena (malaise, irritability, headache, insomnia, chills, fever), can cause skin burns and sunstroke.

Folk remedies for sunburn

water procedure. If the skin is burnt, frequent soaking of the tanned places with soft water or raw potato juice helps. With these remedies, heat and tanned skin color are easily destroyed and the upper skin is strengthened, which often remains uneven and rough.

Cucumber Manipulations:

1. Seed tincture for freckles. Prepared with vodka in a ratio of 1:10. Infuse for two weeks, strain. Before use, dilute the tincture with water also in a ratio of 1:10 and wipe the face daily until the desired result is obtained. It is used as a remedy that protects the skin from sunburn and the appearance of freckles. You can also make a mask from this composition for 5-10 minutes.

2. Vodka tincture of the upper skin of cucumbers for sunburn. Wipe face and hands.

Yogurt. To some extent, it will protect the skin from sun exposure.

Cologne, vodka. With persistent redness of skin areas, they can be smeared with cologne or vodka and refrain from further sun exposure until the redness disappears.

Sour milk or lemon juice suitable for reducing uneven pigmentation caused by sunburn - wipe exposed skin.

Folk remedies for sunburn

1. Take a little raw egg yolk in the palm of your hand and generously grease your face. When the yolk dries, wash off with soap and water. You will notice the result immediately.

2. Peel the potato tubers, grate on a fine grater and squeeze the juice through cheesecloth. Lubricate their face with it or moisten a gauze napkin in it and apply on the affected areas of the skin. Potato juice has an anti-inflammatory effect, so it is used in the treatment of sunburn. Juice can be mixed with wheat flour and apply a mask on the face for 15-20 minutes.

3. Boil a few potato tubers in their skins, peel, mash in a puree and mix with fresh sour cream or cream until the consistency of sour cream. Apply the mixture in a warm form on the face for 10-15 minutes, then wipe the skin with a cotton swab.

Tea. For sunburn, apply a compress of strong brewed tea (a teaspoon of tea - 1/4 cup boiling water, leave for 30-40 minutes, strain). Procedures are carried out 2-3 times a day for 20-30 minutes. Compresses relieve pain and burning sensation. If you pre-lubricate the skin of the face or other parts of the body with strong brewed tea, this prevents the occurrence of sunburn.

Pharmaceutical camomile. Chamomile infusion (1 tbsp per glass of boiling water, leave for 30 minutes) is used for lotions and compresses for sunburn. Or add an alcohol tincture of chamomile to any oily or fortified cream. A cream with this additive helps with skin irritation and sunburn.

Aloe. Burnt areas of the skin can be lubricated with juice from fresh aloe leaves. Aloe juice diluted with boiled water (1: 1) is also used. Apply impregnated wipes on the burnt surface 1-2 times a day every 5-10 minutes for an hour.

Watermelon. With burns, a lotion prepared from equal parts of watermelon and cucumber juice helps well.

Cabbage. Apply fresh cabbage leaves to the burned area.

St. John's wort. Take 1 tbsp. l. dry grass (leaves and flowers) of St. John's wort, pour a glass of boiling water, boil for 10-15 minutes and immediately strain. Use for lotions and wiping for burns. St. John's wort is also effective: take 3 tbsp. l. dried and chopped herbs or St. Strain the resulting extract through cheesecloth. Store the oil in the refrigerator. It is used for burns, wounds that do not heal for a long time, for lubricating very dry facial skin, for inflammatory processes and skin irritation.

insidious melanoma

A beautiful tan is a double-edged sword

“Severe sunburn in children doubles the risk of developing melanoma,” Anna Kubanova, chief specialist in dermatovenereology and cosmetology of the Russian Ministry of Health and Social Development, said at the meeting. - You can stay in the sun only under the protection of sunscreen, this is especially important for children. They need a filter that protects their skin as much as possible from the harmful effects of the sun.”

According to her, melanoma is the most malignant cancer, and its insidiousness is that sometimes it affects a small surface, and the patient may be unaware for a long time that he has a malignant neoplasm. Such a neoplasm, even if it looks harmless, can lead to a serious illness.

A beautiful tan is a double-edged sword. As already mentioned, it has its own negative effect - this is the development of photoaging, i.e., premature aging of the skin under the influence of ultraviolet radiation, the risk of developing cancer and various skin diseases.

As Anna Kubanova explained, photoaging occurs not only in people with white skin, but can develop in dark-skinned and even dark-skinned people. Often it also manifests itself in those who, by the nature of their profession, are constantly exposed to ultraviolet radiation, as well as in those who abuse tanning in solariums or on the coast. Basically, everyone gets old. But in those who abuse the sun, signs of skin aging appear decades earlier. Therefore, any skin type needs protection from the sun. Sunscreens and other means of protection have been created for this.

What is the Sun? On the scale of the visible universe, this is just a tiny star on the outskirts of the galaxy, which is called the Milky Way. But for the planet Earth, the Sun is not just a hot bunch of gas, but a source of heat and light necessary for the existence of all life.

Since prehistoric times, the daylight has been an object of worship, its movement across the firmament has been associated with the manifestation of divine powers. Studies of the Sun and its radiation began even before the adoption of the heliocentric model of Nicolaus Copernicus, the greatest minds of ancient civilizations puzzled over his riddles.

Technological progress has given humanity the opportunity to study not only the processes inside and on the surface of the Sun, but also changes in the Earth's climate under its influence. Statistical data allow us to give a clear answer to the question of what solar radiation is, how it is measured and to determine its impact on living organisms that inhabit the planet.

What is called solar radiation

The nature of solar radiation remained unclear until, at the beginning of the 20th century, the eminent astronomer Arthur Eddington suggested that the source of the colossal solar energy is the thermonuclear fusion reactions that occur in its depths. The temperature near its core (about 15 million degrees) is sufficient for the protons to overcome the force of mutual repulsion and, as a result of the collision, form Helium nuclei.

Subsequently, scientists (in particular, Albert Einstein) discovered that the mass of the Helium nucleus is somewhat less than the total mass of the four protons from which it is formed. This phenomenon is called the mass defect. After tracing the relationship between mass and energy, scientists found that this excess is released in the form of gamma quanta.

When passing the path from the core to the surface of the Sun through the layers of its constituent gases, gamma quanta are crushed and turn into electromagnetic waves, among which is the light visible to the human eye. This process takes about 10 million years. And it takes only 8 minutes to reach the solar radiation of the earth's surface.

Solar radiation includes electromagnetic waves with a wide range and the solar wind, which is a stream of light particles and electrons.

What are the types of solar radiation and its characteristics

At the boundary of the Earth's atmosphere, the intensity of solar radiation is a constant value. The energy of the Sun is discrete and is transferred in portions (quanta) of energy, but their corpuscular contribution is relatively small, so the sun's rays are considered as electromagnetic waves that propagate evenly and rectilinearly.

The main wave characteristic is the wavelength, with which the types of radiation are distinguished:

• radio waves;
• infrared (thermal);
• visible (white) light;
• ultraviolet;
• gamma rays.

Solar radiation is represented by infrared (IR), visible (VS) and ultraviolet (UV) radiation in the ratio of 52%, 43% and 5%, respectively. The quantitative measure of solar radiation is considered to be energy illumination (energy flux density) - radiant energy arriving per unit of time per unit of surface.

Distribution of solar radiation over the earth's surface

Most of the radiation is absorbed by the earth's atmosphere and heats it up to the usual temperature for living organisms. The ozone layer transmits only 1% of ultraviolet rays and serves as a shield against more aggressive short-wave radiation.

The atmosphere absorbs about 20% of the sun's rays, scatters 30% in different directions. Thus, only half of the radiant energy, called direct solar radiation, reaches the earth's surface.

Several factors influence the intensity of direct solar radiation:

• the angle of incidence of the sun's rays (geographical latitude);
• distance from the point of impact to the Sun (season);
• the nature of the reflective surface;
• transparency of the atmosphere (cloudiness, pollution).

Scattered and direct radiation make up the total solar radiation, the intensity of which is measured in calories per unit surface. It is clear that solar radiation has an effect only in the daytime and is distributed unevenly over the earth's surface. Its intensity increases as it approaches the poles, however, snow reflects a large proportion of radiant energy, as a result of which the air does not heat up. Therefore, the total indicator decreases as you move away from the equator.

Solar activity shapes the Earth's climate and affects the life processes of the organisms that inhabit it. On the territory of the CIS countries (in the northern hemisphere), diffuse radiation prevails in the winter season, and direct radiation in the summer.

Infrared radiation and its role in the life of mankind

Solar radiation is represented predominantly invisible to the human eye. It is it that heats the earth's soil, which subsequently gives off heat to the atmosphere. Thus, the temperature and habitual climatic conditions are optimal for life on Earth.

In addition to the Sun, all heated bodies are sources of infrared radiation. All heating devices and devices that allow you to see more or less heated objects in conditions of poor visibility work according to this principle.

The fact that a person is not able to perceive infrared light does not reduce its effect on the body. This type of radiation has found application in medicine due to the following properties:

• expansion of blood vessels, normalization of blood flow;
• an increase in the number of leukocytes;
• treatment of chronic and acute inflammation of internal organs;
• prevention of skin diseases;
• removal of colloid scars, treatment of non-healing wounds.

Infrared thermographs allow timely detection of diseases that cannot be diagnosed using other methods (blood clots, cancerous tumors, etc.). Infrared radiation is a kind of "antidote" against negative ultraviolet radiation, therefore its healing properties are used to restore the health of people who have been in outer space for a long time.

The mechanism of action of infrared rays is not fully understood and, like any type of radiation, if used improperly, can be harmful to human health. Treatment with infrared rays is contraindicated in the presence of purulent inflammation, bleeding, malignant tumors, insufficiency of cerebral circulation and the cardiovascular system.

Spectral composition and properties of visible light

Light beams propagate in a straight line and do not overlap each other, which raises a fair question why the world around us strikes with a variety of different shades. The secret lies in the basic properties of light: reflection, refraction and absorption.

It is known for certain that objects do not emit light, it is partially absorbed by them and reflected at different angles depending on the frequency. Human vision has evolved over the centuries, but the retina of the eye can only perceive a limited range of reflected light in the narrow gap between infrared and ultraviolet radiation.

The study of the properties of light has given rise not only to a separate branch of physics, but also to a number of non-scientific theories and practices based on the effect of color on the mental and physical state of the individual. Using this knowledge, a person decorates the surrounding space in the most pleasing color for the eyes, which makes life as comfortable as possible.

Ultraviolet radiation and its effect on the human body

The ultraviolet spectrum of sunlight consists of long, medium and short waves, which differ in physical properties and the nature of the impact on living organisms. Ultraviolet rays, which belong to the long-wave spectrum, are mainly scattered in the atmosphere and do not reach the earth's surface. The shorter the wavelength, the deeper the ultraviolet penetrates into the skin.

Ultraviolet radiation is essential for sustaining life on Earth. UV rays have the following effects on the human body:

• saturation with vitamin D, necessary for the formation of bone tissue;
• prevention of osteochondrosis and rickets in children;
• normalization of metabolic processes and synthesis of beneficial enzymes;
• activation of tissue regeneration;
• improvement of blood circulation, expansion of blood vessels;
• increased immunity;
• removal of nervous excitement by stimulating the production of endorphins.

Despite the long list of positive qualities, sunbathing is not always effective. Prolonged exposure to the sun at unfavorable times or during periods of abnormally high solar activity nullifies the beneficial properties of UV rays.

Ultraviolet irradiation in high doses has the opposite result as expected:

• erythema (reddening of the skin) and sunburn;
• hyperemia, puffiness;
• increase in body temperature;
• headaches;
• dysfunction of the immune and central nervous systems;
• loss of appetite, nausea, vomiting.

These signs are symptoms of sunstroke, in which the deterioration of a person's condition can occur imperceptibly. Procedure for sunstroke:

• move the person from the area exposed to direct sunlight to a cool place;
• put on your back and raise your legs to an elevation to normalize blood circulation;
• rinse your face and neck with cool water, preferably make a compress on your forehead;
• provide the opportunity to breathe freely and get rid of tight clothing;
• for half an hour, give a drink of a small amount of clean cold water.

In severe cases, with loss of consciousness, it is necessary to call an ambulance team and, if possible, bring the victim to his senses. Medical assistance to the patient consists in the emergency administration of glucose or ascorbic acid intravenously.

Safe tanning rules

UV rays stimulate the synthesis of a special hormone melanin, with the help of which human skin darkens and takes on a bronze hue. Disputes about the benefits and harms of tanning have been going on for decades.

It has been proven that sunburn is a protective reaction of the body to ultraviolet radiation, and excessive sunbathing increases the risk of malignant tumors.

If the desire to pay tribute to fashion prevails, you need to understand what solar radiation is, how to protect yourself from it and follow simple recommendations:

• sunbathe gradually exclusively in the morning or evening;
• do not stay in direct sunlight for more than an hour;
• apply protective agents to the skin;
• drink more pure water to avoid dehydration;
• include in the diet foods that contain vitamin E, beta-carotene, tyrosine and selenium;
• limit the consumption of alcoholic beverages.

The reaction of the body to ultraviolet radiation is individual, so the time for sunbathing and their duration should be selected taking into account the type of skin and the state of human health.

Tanning is highly contraindicated for pregnant women, the elderly, people with skin diseases, heart failure, mental disorders and in the presence of malignant tumors.

The number of tanning fans in Russia is growing every year. However, doctors do not get tired of repeating that the sun's rays are the cause of many serious diseases. What are the benefits and harms of tanning?

In the 80s of the XIX century in America and Europe, a tanned body was considered beautiful and desirable, which many people aspired to. This gave scientists a lot of reasons and materials for research. They found that skin changes, called age-related, for the most part do not depend on the number of years a person has lived, but on the harmful effects of ultraviolet radiation, which is responsible for the appearance of a tan.

So there was a theory of photoaging - premature fading of the skin under the influence of UV radiation. It is confirmed by the data that the skin of the inhabitants of the southern countries ages faster than those who are not spoiled by the sun. In addition, open areas of the body that are not protected by clothing undergo various changes faster.

Mechanism of photoaging

Penetrating into the skin, UV rays meet the natural UV filter - melanin, which blocks more than 90% of UV radiation. Thus, sunburn is nothing more than a reaction of the skin to the traumatic effect of solar radiation. Now many people know that prolonged exposure to ultraviolet radiation contributes to the development of melanoma, skin cancer, accelerates aging and the appearance of wrinkles.

Types of UV radiation

Types of sunbeams
Ultraviolet radiation is divided into three components: rays A, B and C (UVA, UVB, UVC rays, respectively). As sunlight passes through the Earth's atmosphere, the most dangerous UVC rays and about 90% of mid-range UVB rays are absorbed by ozone, oxygen and carbon dioxide. Therefore, the radiation that reaches a person contains a large amount of ultraviolet UVA and a small amount of UVB.

Why UVB rays are dangerous
UVB rays produce melanin, cause photoaging of the skin, and stimulate the development of most types of skin cancer, but they are blocked by the protective substances found in sunscreens.

Why are UVA rays dangerous?
UVA rays are less active than UVB in stimulating the development of many types of skin cancer, but they contribute to the formation of melanoma - the most dangerous type of skin cancer. In addition, this radiation is not blocked by many solar filters, so the main protection against it is clothing.

Why is ultraviolet dangerous to humans:

• it reduces the production of collagen - a protein of the connective tissue of the body, due to the lack of which the skin loses its elasticity and wrinkles appear on it;
• it provokes coarsening and thickening of the stratum corneum of the skin, as a result of which it becomes dry, dull and rough;
• it provokes vascular changes, violation of skin pigmentation, as well as the development of neoplasms.

About the benefits of the sun

A place under the sun
Despite the danger of ultraviolet radiation for the body, in small doses it can be beneficial. To do this, it is enough just a few times a week to expose your face or hands to sunlight for 10-15 minutes.

Healing ultraviolet:

• under the influence of ultraviolet radiation, vitamin D is synthesized in the body, which regulates calcium metabolism and serves as a building material for bone tissue;
• sunlight activates the immune system, increases the body's resistance to viruses and infections;
• the sun has a positive effect on the human nervous system, increasing the production of endorphins (hormone of joy) and thereby improving mood;
• in small doses, ultraviolet prevents the occurrence of diseases of the cardiovascular system, musculoskeletal system (osteochondrosis, arthritis) and respiratory organs (bronchitis, rhinitis), dermatological diseases (psoriasis, neurodermatitis, eczema, etc.), cerebrovascular insufficiency.

How to sunbathe

You need to start sunbathing little by little, in the morning and evening hours, spending 10 to 15 minutes in the sun with breaks. Both dark and pale-skinned people should definitely use sunscreen that matches their skin type and with the right SPF. Apply them to the skin should be 20-30 minutes before going outside.
Owners of skin that is particularly sensitive to sunlight should stay in the shade as often as possible and use products with the highest SPF factor (Sun Protection Factor). Your eyes and lips also need sun protection, so use sunscreen around your eyes, lip balm with SPF, and wear sunglasses when you go out.

Peelings are considered an effective means of eliminating
symptoms of photoaging of the skin. They have exfoliating
action, as well as restore skin tone and beauty.

Elena Kobozeva, dermatovenereologist, cosmetologist:“Ultraviolet is the main factor in skin aging. With excessive solar exposure, it provokes the so-called fine-wrinkled type of aging. The skin becomes like a shriveled baked apple, covered with a network of small wrinkles. In addition, ultraviolet radiation provokes the formation of age spots. This is especially noticeable at the age of over 35 years. Therefore, in the summer it is necessary to constantly protect the skin with sunscreens with a high protection factor.

Expert: Elena Kobozeva, dermatovenereologist, cosmetologist
Katerina Kapustina

The material uses photographs owned by shutterstock.com

The sun It is not only a source of heat and light. Air, earth, water and plants are completely permeated with his life energy. This energy is so concentrated and active that it would be extremely careless to expose the body to direct sunlight for a long time. Therefore, air and sun baths should be taken gradually.

The sun's rays can improve health and prolong life.- the skin should always be covered with a light tan. The reason for many diseases often lies precisely in the fact that we are too rarely in the sun. And the more the skin will absorb the sun's rays, the greater will be the supply of bactericidal energy.

There are certain rules for sunbathing. Start with short periods, gradually increasing them little by little. The best time for sunbathing is between 7 and 10 am. Between 11 a.m. and 3 p.m. the sun's rays are at their hottest and can carry radiation. Staying in the sun for more than an hour without a break is not recommended. It is better to take a walk on a sunny day than to lie still. Do not sleep or eat in direct sunlight.

Don't forget about your home, let in more sunlight and air - the guarantees of health. Take advantage of these precious gifts of nature in spring and summer when the sun is at its strongest. Then health and joy will become your best friends and will never leave you.

The sun has a huge positive effect on the human body., stabilizing blood circulation. Therefore, in the summer, the number of deaths from a heart attack decreases, the heartbeat and pulse become more frequent, blood vessels expand and, as a result, blood flow to the skin increases, which makes it look much better. Muscles become more elastic, metabolism increases, food is processed better, fats break down faster, protein is easier to digest.

solar energy stimulates the brain. Even a short exposure to the sun significantly improves brain activity.

Sun rays stimulate the immune system, and sunlight is essential for healthy teeth and bones. With its lack, children develop rickets, and osteoporosis in old age is more likely to affect people who lead a sedentary lifestyle and rarely go to the sun.

Ultra-violet rays slow down the growth of cancer cells. With the help of sunlight, our body produces interleukocytes and interferon - substances that successfully fight cancer cells. People who rarely go out into the sun have a higher risk of getting cancer.

Many people know the benefits of sunlight to improve vision. You need to look at the sun at sunrise, without taking your eyes off, starting from a few seconds, gradually increasing the time of the procedure.

The sun's rays have a healing effect on the entire body.. Blood circulation and the work of the heart muscle are activated, the nervous system is strengthened, physical activity is increased, and the supply of organs and bones with calcium is improved.

But solar procedures in case of overdose have side effects. An overdose of solar energy is fraught with overheating of the body, decay and death of leukocytes in the blood. The result is a headache, fatigue, excessive excitability, irritability and insomnia. To avoid this, it is necessary to know the measure and not be under the direct rays of the sun during the period of solar radiation - from 11.00 to 15.00 hours. Remember this.

You can not use glycerin, petroleum jelly and other mineral fats to protect the skin from the sun and soften it. To protect yourself from possible overheating and burns, you can cover the body with special sunscreen, but remember that they do not guarantee 100% protection from burns.

To protect your hair from drying out in the sun and when swimming, you need to wear a bathing cap, and before going to the beach, rub a mixture of equal parts of castor oil and any vegetable oil into the scalp. In addition, it would be advisable to recall the mandatory headgear in order to avoid sunstroke (this is necessary after 11 am).

Before a sun bath, do not wash your face and body with soap, do not wipe your skin with cologne or other alcohol tinctures and lotions.

Then, noticing redness on the skin and burning, go into the shade as soon as possible, rinse your face and body with fresh water. In case of severe sunburn, lubricate the burnt places with sour cream, butter, cover the body with cabbage leaves.

Always take a shower after the beach to free your clogged skin pores.

Many, after swimming in the sea or river, remain in a wet bathing suit, allowing it to dry on the body. But this can lead to various diseases, sometimes extremely severe. A warm and humid environment allows bacteria to thrive and multiply, causing fungal infections. Therefore, after bathing, be sure to change into dry clothes.

The sun is the main source of energy on Earth. Without it, the existence of life would be impossible. And although everything literally revolves around the Sun, we very rarely think about how our star works.

Structure of the Sun

To understand how the Sun works, you first need to understand its structure.

• Core.
• Radiant transfer zone.
• convective zone.
• Atmosphere: photosphere, chromosphere, corona, solar wind.

The diameter of the solar core is 150-175,000 km, about 20-25% of the solar radius. The core temperature reaches 14 million degrees Kelvin. Inside, thermonuclear reactions constantly occur with the formation of helium. It is in the nucleus as a result of this reaction that energy is released, as well as heat. The rest of the Sun is heated by this energy, it passes through all the layers to the photosphere.

The radiative transfer zone is located above the nucleus. Energy is transferred by emitting photons and absorbing them.

Above the radiative transfer zone is the convective zone. Here, the transfer of energy is carried out not by reemission, but by the transfer of matter. With high speed, the colder matter of the photosphere penetrates into the convective zone, and the radiation from the radiative transfer zone rises to the surface - this is convection.

The photosphere is the visible surface of the Sun. Most of the visible radiation comes from this layer. Radiation from deeper layers no longer penetrates into the photosphere. The average layer temperature reaches 5778 K.

The chromosphere surrounds the photosphere, it has a reddish hue. From the surface of the chromosphere constantly occur emissions - spicules.

The last outer shell of our star is the corona, composed of energetic eruptions and prominences that form the solar wind that spreads to the farthest corners of the solar system. The average temperature of the corona is 1-2 million K, but there are areas with 20 million K.

The solar wind is a stream of ionized particles propagating to the edges of the heliosphere at a speed of about 400 km/s. Many phenomena on Earth are associated with the solar wind, such as the aurora and magnetic storms.

solar radiation

The solar plasma has a high electrical conductivity, which contributes to the appearance of electric currents and magnetic fields.

The sun is the strongest emitter of electromagnetic waves in the world, which gives us:

• ultra-violet rays;
• visible light - 44% of solar energy (mainly yellow-green spectrum);
• infrared rays - 48%;
• x-ray radiation;
• radiation radiation.

Only 8% of the energy is spent on ultraviolet, X-ray and radiation radiation. Visible light lies between the infrared and ultraviolet rays.

The Sun is also a powerful source of non-thermal radio waves. In addition to all kinds of electromagnetic rays, a constant stream of particles is emitted: electrons, protons, neutrinos, and so on.

All types of radiation exert their influence on the Earth. This is the impact we are experiencing.

Exposure to UV rays

Ultraviolet rays affect the Earth and all living beings. Thanks to them, the ozone layer exists, since UV rays destroy oxygen, which is modified into ozone. The Earth's magnetic field, in turn, forms the ozone layer, which, paradoxically, weakens the power of UV exposure.

Ultraviolet affects living organisms and the environment in many ways:

• promotes the production of vitamin D;
• has antiseptic properties;
• causes sunburn;
• enhances the work of hematopoietic organs;
• increases blood clotting;
• the alkaline reserve increases;
• disinfects surfaces of objects and liquids;
• stimulates metabolic processes.

It is ultraviolet radiation that contributes to the self-purification of the atmosphere, eliminates smog, smoke and dust particles.

Depending on latitude, the strength of exposure to UV radiation varies greatly.

Exposure to IR rays: why and how the sun warms

All heat on Earth is infrared rays, which appear due to the thermonuclear fusion of hydrogen to form helium. This reaction is accompanied by a huge release of radiant energy. About 1000 watts per square meter reaches the ground. It is for this reason that IR radiation is often called thermal radiation.

Surprisingly, the Earth acts as an infrared emitter. The planet, as well as the clouds, absorb infrared rays and then re-radiate this energy back into the atmosphere. Substances such as water vapor, water droplets, methane, carbon dioxide, nitrogen, some fluorine and sulfur compounds emit infrared rays in all directions. It is thanks to this that the greenhouse effect takes place, which maintains the surface of the Earth in a constantly heated state.

Infrared rays not only heat the surfaces of objects and living beings, but also have other effects:

• disinfect;
• improve metabolism;
• stimulate blood circulation;
• relieve pain;
• normalize the water-salt balance;
• strengthen immunity.

Why is the sun weak in winter?

Since the Earth revolves around the Sun with some axial tilt, the poles deviate at different times of the year. In the first half of the year, the North Pole is turned towards the Sun, in the second - the South. Accordingly, the angle of exposure to solar energy changes, as well as power.