Bright sunshine is a source of excellent mood and vivacity. In cloudy weather, many people feel depressed, succumb to depression. Despite this, everyone knows that bad weather will soon end and the sun will appear in the sky. It has been familiar to people since childhood, and few people think about what this luminary represents. The most famous information about the Sun is that it is a star. However, there are many more interesting facts that may be of interest to both children and adults.
What is the sun?
Now everyone already knows that the Sun is a star, and not a huge luminous ball resembling a planet. It is a cloud of gases with a core inside. The main component of this star is hydrogen, which occupies about 92% of its total volume. About 7% is helium, and the remaining percentage is shared among other elements. These include iron, oxygen, nickel, silicon, sulfur and others.
Most of the star’s energy is generated as a result of thermonuclear fusion of helium from hydrogen. Information on the Sun, collected by scientists, allows us to classify it as G2V by spectral classification. This type is called the "yellow dwarf". In this case, the sun, contrary to popular belief, shines with white light. A yellow glow appears as a result of the dispersion and absorption by the atmosphere of our planet of the short-wave part of the spectrum of its rays. Our luminary - the Sun - is part of the Milky Way galaxy. The star is located at a distance of 26,000 light years from its center, and one revolution around it takes 225-250 million years.
Solar radiation
The Sun and the Earth are separated by a distance of 149600 thousand km. Despite this, solar radiation is the main source of energy on the planet. Not all of its volume passes through the Earth’s atmosphere. The energy of the sun is used by plants in the processes of photosynthesis. In this way, various organic compounds are formed and oxygen is released. Solar radiation is also used to generate electricity. Even the energy of stocks of peat and other minerals appeared in ancient times under the influence of the rays of this bright star. Particular attention deserves the ultraviolet radiation of the sun. It has the properties of an antiseptic, can be used to disinfect water. Ultraviolet radiation also affects biological processes in the human body, causing tanning on the skin, as well as the production of vitamin D.
Sun Life Cycle
Our star - the Sun - is a young star belonging to the third generation. It contains a large number of metals, which indicates the formation of it from other stars of previous generations. According to scientists, the Sun is about 4.57 billion years old. Given the fact that the life cycle of a star is 10 billion years, now it is in its middle. At this stage, the thermonuclear synthesis of helium from hydrogen takes place in the core of the sun. Gradually, the amount of hydrogen will decrease, the star will become hotter, and its luminosity - higher. Then, the hydrogen reserves in the core will run out completely, part of it will go into the outer shell of the Sun, and helium will begin to condense. The processes of extinction of the star will continue for billions of years, but still lead to its transformation first into a red giant, then into a white dwarf.
Sun and Earth
Life on our planet will depend on the degree of solar radiation. After about 1 billion years, it will be so strong that the Earth’s surface heats up significantly and becomes unsuitable for most life forms, they can only remain in the depths of the oceans and in the polar latitudes. By the age of the Sun at about 8 billion years, conditions on the planet will be close to those that are now on Venus. There will be no water left; it will all evaporate into space. This will lead to the complete disappearance of various life forms. As the core of the Sun shrinks and its outer shell increases, the probability of absorption of our planet by the outer layers of the star’s plasma will increase. This will not happen only if the Earth revolves around the Sun at a farther distance as a result of a transition to another orbit.
A magnetic field
Information about the Sun, collected by the researchers, indicates that it is a magnetically active star. The magnetic field created by him changes its direction every 11 years. His tension also varies over time. All these transformations are called solar activity, which is characterized by special phenomena, for example, sunspots, wind, flashes. They are the cause of auroras and geomagnetic storms, which negatively affect the operation of some devices on Earth, the well-being of people.
Solar eclipses
Information about the Sun, collected by ancestors and survived to this day, contains references to its eclipses from antiquity. A large number of them are also described during the Middle Ages. A solar eclipse is the result of the closure of a star by the moon from an observer on Earth. It can be complete when, at least from one point on our planet, the solar disk is completely and partially hidden. There are usually two to five eclipses per year. At a certain point on Earth, they arise with a time difference over 200-300 years. Lovers of viewing the sky, the Sun can also see an annular eclipse. The moon covers the star’s disk, but due to its smaller diameter, it cannot eclipse it completely. As a result, the “ring of fire" remains noticeable.
It is worth remembering that observing the Sun with the naked eye, especially with binoculars or a telescope, is very dangerous. This can lead to irreversible visual impairment. The sun is relatively close to the surface of our planet and shines very brightly. Without a threat to eye health, you can look at it only during sunrises and sunsets. The rest of the time, you need to use special dimming filters or project an image obtained using a telescope onto a white screen. This method is the most acceptable.