The sun is the center point of our sun system and origin of all life. The sun shines already 5 billion years with its present power. Even the fossil energy sources are stored solar energy. Most of the renewable energy sources also come directly or indirectly from the sun. The sun consits of about 80 % hydrogen, 20 % helium and only 0.1 % other elements. The following table compares the most important data of sun and earth.