What is Known About the Sun?

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The Sun is a huge source of energy. This energy travels into space in the form of waves of light and heat. The hydrogen is the main fuel that burns in the Sun. The temperature at the centre may be 15 million oC. The surface of the Sun is known as the photosphere. This is the coolest part of the Sun with a temperature of about 60000C. It takes about 8.3 minutes for the light to travel from the Sun to the Earth. The Sun is a star which is about 4.6 billion years old. It spins around its axis once every 27.4 days. It has a diameter of about 1,380,000 million km which is about 109 times the diameter of the earth. The Sun can easily house about million earths in itself.

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