Our Sun is one of many billions of stars in our galaxy. Although it is a relatively insignificant star in terms of the vastness of the universe, it is of major importance to man.
Without the Sun, there would be no life on our planet. We would have neither air to breathe nor water to drink. There would be no evaporation, no atmospheric movements and no rain. However, the Sun also has negative aspects, as for instance its ultraviolet_radiation, which is harmful to us. According to theoretical calculations, the Sun is 4. 5 billion years old. In the first 50 million years of its "life", it shrank to its current size. Half of its life is already over and it will become a red giant in five billion years. Our proximity to the Sun, only 150 million kilometers distant, gives us the unique opportunity to study stars in general.
Light from the Sun takes only eight minutes to reach the Earth, while the light from the next nearest star takes 4.3 years. The Sun is the basis of all life and all forms of energy.
The Sun has always been venerated and sometimes even worshipped. The most significant Sun cult existed about 3000 years ago in Egypt. Earlier gods were replaced by the sun god Re, who travels across the sky in the "bark of eternity". The Sun was also of central importance for the Aztec and Inca peoples of South America.
The regular movements of the Sun were observed and described very early on. Rare occurrences were recorded already in early history. A solar_eclipse was for example described in detail in 763BC in Babylon.
Chinese astronomers observed the first sunspots as early as 200 BC. With the invention of the telescope in the 17th century these were examined more closely. For a long time, sunspots were considered the only activity of the Sun.
