The sun is the principal source of energy for the earth. Each year this immense, nuclear furnace bathes the earth with energy equivalent to that contained in 250 million million tons of coal, about 100,000 tons for each person on earth. In one day enough sun energy shines upon Lake Erie alone to meet the needs (if it could be fully utilized) of the entire American populace for a whole year.
The sun is an enormous nuclear machine. It runs by fusing ions of light hydrogen (H1) to form the heavier atoms of helium (He4). The energy released becomes heat. Every minute about 40 billion tons of hydrogen atoms are fused on the sun.
The sun is indirectly responsible for many other forms of energy too. The sun's rays cause tropical air to warm up and rise while cooler air from polar regions flows in to replace it. This creates winds that can be used for sailing ships, grinding grain, or even for producing electricity from windmill-powered generators. Coal is the fossilized remains of plants that stored solar energy in their cells long ago. Likewise, the chemical energy in oil is the light and radiant energy of the sun stored in the cells of living things in the past.
The sun is an enormous nuclear machine. It runs by fusing ions of light hydrogen (H1) to form the heavier atoms of helium (He4). The energy released becomes heat. Every minute about 40 billion tons of hydrogen atoms are fused on the sun.
The sun is indirectly responsible for many other forms of energy too. The sun's rays cause tropical air to warm up and rise while cooler air from polar regions flows in to replace it. This creates winds that can be used for sailing ships, grinding grain, or even for producing electricity from windmill-powered generators. Coal is the fossilized remains of plants that stored solar energy in their cells long ago. Likewise, the chemical energy in oil is the light and radiant energy of the sun stored in the cells of living things in the past.