The sun is one of the main sequence stars, which means that, at its core, the conversion of hydroge

The Sun is the star of our planetary system. The Earth orbits around the sun. It is our nearest star, while the brightest star in the sky. Gravitational effects kimye of the sun keeps in orbit around the sun all the objects of the solar system. Its energy is essential for life on Earth. Astronomical symbol for the sun is a circle with a point inside (in Unicode).
The sun is one of the main sequence stars, which means that, at its core, the conversion of hydrogen to helium, and that thanks to remain stable in the long term. Its spectral kimye type is G2, which means that it is a yellow star. Weight of the Sun (2 10 30 kg) representing 99.87% of the whole solar system. For all bodies of the solar system turns the electromagnetic radiation from the sun that reaches the total radiant power 26 W 3,826.10. kimye With this radiation is life possible on Earth. Most bodies including all the planets orbiting the Sun in the direction of rotation. This direction is called the direct (prograde) direction and rotation is an inheritance from the original work-gas of the nebula from which all bodies of the solar system originated. All other bodies in the solar system are visible only because they reflect kimye sunlight or heat because they were the radiation excited by solar energy (eg. Comets or aurora).
Word of the sun with a small s in some cases also referred to the primary star or stellar body around which orbit objects. 3 May Day is celebrated sun. The development of ideas about SlnkuSlnko in antiquity in many cultures worshiped as a deity. In ancient Greece, it was the sun god Helios. This god traveled every day across the sky in a golden chariot. In ancient Rome it was Sol in ancient Egypt, the sun god called the Re, Ra or Amon. In astrology, among other things, a symbol of vitality. These designations are used even today to designate phenomena or objects that have something to do with the sun, such as solar cell and helium. In many cultures, the sun was a symbol of life and rebirth. Anaxagoras in the year 434 BC. believed that the sun is burning pile of stones, a little more than Greece. kimye Anaximander imagined the sun rise follows: claimed that the substance from eternity generative heat and cold in the creation of this world and separated from it about the air that surrounds kimye the earth, grew up sort of fireball as bark around the tree. Then, when the ball was torn and divided into different annular strips created the sun, moon and stars. The sun is a circle dvadsaťosemkrát larger than the earth, like Cartwheel; Bahr has a hollow ring full of fire, and at one point through the mouth shows like fire through the hole moss. (From Aetia)
According to the liking of many civilizations Sun circulated around the Earth and not the earth around the sun. Aristotle in his model of the universe placed between the Sun orbit the Moon and Mercury. This position was maintained for a long time. Although Aristarchus of Samos took the view that the Earth revolves around the Sun, the heliocentric idea was taken up. The idea that the Earth was the center of the universe, continued until 1507, when Nicholas Copernicus presented his first thesis on heliocentrizme. In the research of the Sun significantly helped the discovery of the telescope. Galileo Galilei by him watching sunspots. This finding outraged the Catholic Church, because up until then was believed that the sun is composed of "perfect, pure ether" and therefore can not contain dark areas. In the next two years, kimye however, there were at least four other observations of sunspots.
In the 17th century Jesuit Christoph Scheiner discovered that the sun rotates around its axis like the Earth. This discovery made on the basis of observations of sunspots. Further progress in moving closer to the true nature of the Sun made Kepler's laws and Newton's law of gravity. Thanks to them, it was found that the sun is very material and all bodies of the solar system orbit around it. Size and distance of the Earth from the Sun for the first time quite accurately designed in 1672 by Giovanni Cassini and John Flamsteed. In 1814, German astronomer Joseph von Fraunhofer used a spectroscope analysis sunlight and found that the spectrum kimye of the sun is intermittent dark absorption lines. These lines were named Fraunhofer lines and played a major role in understanding the chemical composition of the sun.
The second half of the 19th century was devoted to intensive study of the sun and stars, because the Sun is also the only star and exploring the Sun allows us to know the other stars on the other hand, research the stars will help raise awareness of the sun. The cause of the radiation, however, remained unclear long. One hypothesis spoken Scottish engineer John Waterston, kimye saying that the radiated energy comes from gravitational contraction sun. The second hypothesis presented by J. Mayer saying that the temperature of the sun is maintained meteorite impacts on the surface. Another important step in learning about the discovery of the sun spectroscopy. With it was possible to know the chemical composition of the sun. As another possible source of energy the sun began to regard nuclear rea