Sun

The sun is the most important heavenly body, without no life on earth would be possible. Without the constant river of solar power the earth would be a dead, before cold weather rigid-ends rock ball with an average Temperature over minus 270 degrees Celsius. The sun radiates however already since several billions years, before alone in the form of visible light, inconceivable Energy quantities on earth. The collected solar power would be sufficient, everything Water of the earth's surface, thus all oceans, icebergs, rivers and lakes within to evaporate from only 10 seconds on! Because of the large distance between earth and sun reaches the earth however actually only a half billionth that Solar radiation, which corresponds to a still annually 1.5 quintillion a kwh! Those Sun is that the earth nearest star. Exactly like all other fixed stars, substantially further, produce they are distant from the earth for energy and shine even. In the comparison to the other stars it belongs to the inconspicuous, smaller representatives, on the average only which its mass, their luminosity and their energy production concerns. All other bright stars in the sky, those we with the naked eye to see good can, are clearly, partly even whole substantially more largely and more shine-strongly than it. In the comparison to the earth are those Dimensions of the sun nevertheless enormously. Their energy probably produces the sun by the process of the nuclear fusion in their inside. There must a temperature of approximately 16 million degree and a pressure of approximately 200 billion atmospheres prevail. Under such conditions merge hydrogen atoms, those that Constitutes main part of the sun, to helium, whereby a tiny part that Mass directly according to the famous formula of Albert Einstein: Energy = mass x speed of light in the square (E = mc2) in energy is converted. Those Sun »uses «in such a way per second about 4 million tons of mass. It is however so inconceivably largely that it since its emergence only 0.03% of their mass into energy converted. The sun is the only star, on its surface we details to recognize can. Famous are above all the sunspots, cools places on its surface, those because of the smaller temperature black appear. In this sunspots often giantrie-senhafte eruptions unload themselves, with those radiation and subject into the universe are hurled. On earth if such radiation outbreaks produce the famous polar lights, lead to radio losses and affect the upper atmosphere in more varied, partially not yet whole investigated way. The number of the sunspots and thus the activity of the sun varies in an on the average eleven-year old rhythm. The emergence of this »Sunspot cycle «as well as many other procedures on the sun is to today still a mystery. The sun strives at the moment a calmer Phase against their activity. The last sunspot maximum stepped at the end of of 1989 ; the next minimum is expected approximately in the year 1994. More again High point of the solar activity with many marks is reached around the year 2000.

August Keller

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