Which star is closest to the Earth
Which star is closest to the Earth
The only star in the solar system, and therefore the closest to the Earth, is the Sun. All planets make their movement around it, and therefore the planetary system is named after its star.
Instructions
1
The sun is one of the hundred million stars of the galaxyMilky Way, and in size is approximately on the 4th place among them. According to spectral classification, the Sun belongs to yellow dwarfs, and its age, according to approximate calculations, is about 4.5 billion years. Currently, the Sun is in the middle of its life cycle. The closest star to the Sun is called Proxima Centauri and is 4 light years away. The distance from the planet Earth to the Sun is equal to 150 million km, the distance is 8 minutes. The sun is located at a distance of 26 thousand light years from the center of the galaxy, and the speed of its rotation relative to the center is 1 revolution for 200 million years.
2
When the Sun reaches the age of about 7 billionyears, this star will turn into a red giant. Its outer shells will expand and reach the orbit of the Earth or even Saturn, pushing these planets far back. The star consists of hydrogen by 92% and helium by 7%, having a very complex structure. In the center of the Sun is its core, the radius of which is approximately 150,000 - 175,000 km, which is about 25% of the total radius of the star. At the center of the core, the temperature reaches 14,000,000 K. The nucleus rotates around its own axis at a high rate, which is significantly higher than the outer shells of the star. It is here that as a result of the reaction helium is formed from 4 protons, which releases a large amount of energy. It is something radiated from the photosphere as kinetic energy and light.
3
Over the core of the Sun there is a radiant zonetransport with temperatures in the region of 2-7 million K. This zone is followed by a convective zone with a depth of about 200,000 km. In this zone there is no reradiation and energy transfer, here there is a mixing of the plasma. The surface temperature of this layer reaches 5800 K. The photosphere, which makes up the visible surface of the star, is the main part of the atmosphere of the Sun along with the chromosphere. The last outer shell of the star is the corona, from the outer part of which comes the solar wind - the flow of ionized particles.
4
Life on planet Earth exists in the mainonly thanks to the Sun. The planet rotates around its axis, and every day a person can observe the sunrise and sunset, and at night the stars in the dark sky. On the life of all living things on the planet the Sun has a huge influence: the star participates in photosynthesis, promotes the formation of vitamin D. in the human body. The penetration of the solar wind into the earth's atmosphere is visible to the naked eye. This is the northern lights, which also causes geomagnetic storms. Approximately every 11 years, solar activity decreases or increases.
