The Sun

                                           The Sun

     The Sun is a celestial body lies at the centre of the solar system. Sun is a star because it emits its own light. This is the nearest star to the earth which is estimated with the composition of 10 percent helium and 90 percent hydrogen gases. The diameter of the sun is 1.39 million k.m. Sun accounts 99.86% of mass of the solar system. The sun is 1,300,000 times larger than the earth.

     The heat is generated by the conversion of hydrogen into helium. Sun radiates energy in the form of electro magnetic waves to all directions due to atomic fusion. The energy emitted by the sun is called Solar Radiation. The amount of solar energy reaches on the earth's surface is known as Insolation.

     Sun's innermost layer is Core. Radiative Zone lies around the core. Convection Zone lies around the Radiative Zone. Photosphere lies around Convection Zone, Chromosphere lies around Photosphere and Carona is found around the Photosphere.

   Photosphere and Chromosphere are the atmospheric layers of the sun. The visible parts or the glowing parts of the sun is known as Photosphere or Lightsphere. The outermost layer, Corona is visible during the eclipse only with the help of Coronagraph.

    The Sun Spots are the dark spots of the sun's surface. The flaming parts extending outwards into the sun's Corona is known as Solar Prominence. The temperature of the Corona is 5,500 degree C. In Photosphere 5,730 degree Celsius and in Chromosphere 4,320 degree C. It is believed that the temperature of the core is 15 million degree Celsius.