If you are interested in mythologies of sun god or goddess, you will be able to find numerous versions in different cultures including Chinese, Korean, Japanese, Egyptian, Greek, Indian and many others.
The first slide shows the Indian sun god and Greek sun god. I personally like the story of Greek sun god, Apollo, very much. I think the story of Apollo is comparable to the best of William Shakespeare’s plays.
However everyone here knows that the sun is the only star in our solar system. Comparison between the sun, the earth and other planets in size is shown in the second slide. The sun is much larger than the earth and other planets. Actually the volume of the sun is over one million times larger than that of the earth.
The sun is an enormous ball of burning gases. The main elements of the sun are hydrogen and helium. Since there is no oxygen on the sun, the energy of the sun does not come from general sense of burning hydrogen, but from hydrogen nuclear fusion, a process similar to that happening in a hydrogen bomb when it explodes.
The sun produces enormous light per second and it has been doing that for billions of years. Up to now, the largest power plant in the world is the Chinese Three Gorge power plant, which can produce 18,000 Megawatts (one million) of power per year. However, the sun puts out the same amount of energy in the form of light per second as a billion of the largest power plant in the world would put out in a year. This number is enormous, even difficult to imagine.
The sun light absorbed by the earth atmosphere, oceans and land is called solar energy. The solar energy the earth receives per hour is equivalent to all the energy humans currently consume in a year.
About 0.1% of the solar energy has been captured by photosynthesis, transferring the light energy into chemical energy. Plants make their own food by Photosynthesis, and animals and humans have to eat plants or other animals to obtain their energy. So the energy to sustain almost all the life on the earth comes from the Sun.
Here lists the energy sources originally from the sun. Currently, 86% of energy we are using are form fossil fuels: coal, oil and natural gas. Fossil fuels were solar energy fixed by plants millions of years ago; and bioenergy, hydropower, solar power, wave power, wind power are all originally from solar energy. The only exceptions are nuclear power, tidal energy, and Geothermal energy.
Without the sun, life on the earth simply wouldn’t exist. We are so blessed that the sun provides us with free and clean energy. How can we be grateful enough for the Sun? The only thing we can do is to make good use of the solar energy.
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The above is one of 5-7 min speeches I delivered in my Toastmasters Club.
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