Interesting facts about the Sun

The Sun is one of the stars in our Galaxy (the Milky Way) and the only star in our solar system. We all know that solar radiation supports life on our planet and determines its climate. But how much do you know about this star? In this article, we have prepared answers to the most common questions of mankind about the Sun.


What is the sun made of?

The sun is a huge ball of plasma (that is, ionized gas) consisting mainly of hydrogen (73,46 percent of the mass) and helium (24,85 percent of the mass). Thus, all other elements in the composition of the solar matter account for less than 2 percent.

The main of these remaining elements are oxygen (0,77 percent solar mass), carbon (0,29 percent), iron (0,16 percent), neon (0,12 percent), nitrogen (0,09 percent), silicon (0,07 percent), magnesium (0,05 percent) and sulfur (0,04 percent).


What is the source of solar energy?

The main source of solar energy is the thermonuclear fusion reactions that take place in the interior of this star and are accompanied by the release of a huge amount of energy. The main role here is played by the conversion of hydrogen into helium.

This process is a series of four protons (hydrogen nuclei) joining each other and combining them in a helium nucleus. Since the mass of the latter is less than the sum of the masses of four free protons, part of the mass in this reaction is converted into photon energy.


How big is the solar mass loss due to radiation?

Every second, the Sun loses about 4,3 million tons of its substance to radiation. This amounts to 140 trillion tons per year (a trillion is a number represented by a unit followed by 12 zeros) – such is, for example, the mass of an asteroid with a diameter of 50 kilometers. But the Sun is very large, and at this rate of radiation, it would take 150 billion years for it to lose just one percent of its mass.

Interesting facts about the Sun


How much of the sun's radiation hits the earth?

A little less than half a billionth of solar radiation hits the Earth, but it is its energy that provides favorable conditions for life on our planet.

Although the globe has a hot core, the heat that each square meter of the Earth's surface receives from its interior is 25000 times less than the heat received from the Sun.

If we remember that about 150 million kilometers separate us from our luminary, and its radiation is attenuated in proportion to the square of the distance, then one can only be amazed at how great the power of a thermonuclear reactor called the Sun is.

Interesting fact

Sunlight takes 8 minutes and 17 seconds to reach Earth, while it takes 1,255 seconds from the Moon to Earth.

The impact of the ultraviolet part of the solar spectrum is greatly attenuated by the ozone layer in the Earth's atmosphere, so the intensity of ultraviolet radiation on the Earth's surface varies greatly with latitude. The angle at which the sun is above the horizon at noon affects many types of biological adaptation, such as the color of human skin in different regions of the globe.

The ultraviolet radiation of the Sun has antiseptic properties, allowing it to be used to disinfect water and various objects. It also causes sunburn and has other biological effects, such as stimulating the body's production of vitamin D.


How does a solar eclipse occur?

This phenomenon occurs due to the fact that the Moon closes (eclipses) the Sun completely or partially from an observer on Earth. A solar eclipse is possible only on new moons, when the side of the Moon facing the Earth is not illuminated, and the Moon itself is not visible.

Eclipses are possible only if the new moon occurs near one of the two lunar nodes (the point of intersection of the visible orbits of the Moon and the Sun), no more than about 12 degrees from one of them.

When an observer is in the shadow of the moon, he observes a total solar eclipse. When he is in the penumbra, he can observe a partial solar eclipse. In addition to total and partial solar eclipses, there are annular eclipses. Visually, during an annular eclipse, the Moon passes over the disk of the Sun, but it turns out to be smaller than the Sun in diameter, and cannot completely hide it. This phenomenon is caused by a change in the angular dimensions of the Moon in the sky due to the ellipticity of its orbit.

From 2 to 5 solar eclipses can occur on Earth per year, of which no more than two are total or annular. On average, 100 solar eclipses occur in 237 years, of which 160 are partial, 63 are total, and 14 are annular.

Interesting facts about the Sun


What are solar flares?

Solar flares are strong explosions that cover large areas of the surface layer of the Sun. Flares usually appear in the centers of solar activity (for example, in a group of spots, sometimes between two spots that make up a magnetic pair) and manifest themselves as sharp increases in brightness.

The duration of flashes is usually tens of minutes, and sometimes reaches up to an hour. But the phase in which the main part of the energy is released lasts a few minutes and corresponds to the greatest brightness.

Solar flares are the most powerful of all manifestations of solar activity. The energy of a large flash is approximately 100 times higher than the thermal energy that could be obtained by burning all the reserves of oil and coal on Earth. However, in this case, the flash power does not exceed hundredths of a percent of the power of the total radiation of our star, and there is no noticeable increase in the luminosity of the Sun.

Flares cause a sharp increase in ultraviolet and X-ray radiation from the Sun, as well as a stream of charged particles, whose speeds reach 1000 kilometers per second or more. Having reached our planet in a few hours, these particles give rise to auroras and electromagnetic storms, which sometimes lead to disruptions in the functioning of telecommunication networks and devices. So, for example, on September 2, 1967, a bright solar flare caused an almost two-hour cessation of radio communications throughout the Earth.


You can learn more interesting facts about the Sun from the following documentaries that we have selected for you.


In the video player, you can turn on subtitles and select their translation into any language in the settings


In the video player, you can turn on subtitles and select their translation into any language in the settings



In the video player, you can turn on subtitles and select their translation into any language in the settings


In the video player, you can turn on subtitles and select their translation into any language in the settings