It may be hard for you to believe, but when you look at the stars that shine at night and the sun that shines by day, you are looking at the same kinds of objects!
The sun is really a star. In fact, it's nearest star to the earth. Life as we know it depends on the sun. Without the sun's heat , life could not have started on earth. Without sunlight, there would be no green plants, no animals, no humjan beings.
The sun is 93,000,000 miles from the earth.The volume , or bulk, of the sun is about 1,300,000 times that of the earth! Yet an interesting thing about the sun is that it is not a solid body like the earth.
Here is how we know this: The teperature on the surface of the sun is about 6,000 degrees centigrade. This is hot enough to change any metal or rock into a gas, so the sun must be a globe of gas!
Years ago, scientists believed that the reason the sun shone, or gave off light and heat, was that it was burning. But the sun has been hot for hundreds of millions of years, and nothing could remain burning for that long.
Today scientist believe that the heat of the sun is the result of a process similar to what takes place in an atom bomb. The sun changes matter into energy.
This is different from burning. Burning changes matter from one form to another. But when matter is changed into energy, very little matter is needed to produce a great deal of energy. Twenty eight grams of matter could produce enough energy to melt more than a million tonnes of rock!
So if science is right, the keeps shining because it is constantly changing matter into energy. And just one percent of the sun's mass would provide enough energy to keep it hot for 150 thousand million years!
The sun is really a star. In fact, it's nearest star to the earth. Life as we know it depends on the sun. Without the sun's heat , life could not have started on earth. Without sunlight, there would be no green plants, no animals, no humjan beings.
The sun is 93,000,000 miles from the earth.The volume , or bulk, of the sun is about 1,300,000 times that of the earth! Yet an interesting thing about the sun is that it is not a solid body like the earth.
Here is how we know this: The teperature on the surface of the sun is about 6,000 degrees centigrade. This is hot enough to change any metal or rock into a gas, so the sun must be a globe of gas!
Years ago, scientists believed that the reason the sun shone, or gave off light and heat, was that it was burning. But the sun has been hot for hundreds of millions of years, and nothing could remain burning for that long.
Today scientist believe that the heat of the sun is the result of a process similar to what takes place in an atom bomb. The sun changes matter into energy.
This is different from burning. Burning changes matter from one form to another. But when matter is changed into energy, very little matter is needed to produce a great deal of energy. Twenty eight grams of matter could produce enough energy to melt more than a million tonnes of rock!
So if science is right, the keeps shining because it is constantly changing matter into energy. And just one percent of the sun's mass would provide enough energy to keep it hot for 150 thousand million years!
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