The Sun

1. The Sun

2. Introduction to The Sun • Our sun is a star located at the center of our Solar System. It is a huge, spinning ball of hot gas and nuclear reactions that light up the Earth and provides us with heat. The Greeks called the Sun "Helios"; the Romans called it "Sol."

3. COMPOSITION OF THE SUN • The Sun is made up of gases. It is composed of about 75% hydrogen and 25% helium. About 0.1% is metals ). • The Sun formed 4.5 billion years ago

4. THE TEMPERATURE OF THE SUN • The Sun's core can reach 10 to 22.5 milliondegrees Fahrenheit. The surface temperature is approximately 9,900°F. The outer atmosphere of the Sun gets extremely hot again, up to 1.5 to 2 million degrees. • The temperature of the Sun is determined by measuring how much energy (both heat and light) it emits.

6. The Sun’s ENERGY PRODUCTION • At the Sun's core the changing hydrogen into heliumproduces large amounts of energy. This is called nuclear fusion. • Nuclear fusion releases an enormous amount of this heat and light energy into the Solar System (including Earth).

7. AGE OF THE SUN • The Sun formed 4.5 billion years ago, as the solar system coalesced from a cloud of gas and dust.

8. 1. Is the Sun a star, a planet, or a nebula?_______________________ 2. Is the Sun solid, liquid, or gaseous ?_______________________ 3. What did the Greeks call the Sun?________________________4. Where is the Sun hottest?_______________________ 5. Where is the Sun coolest?_______________________ 6. What element is there the most of on the Sun?_______________________ 8. What is the name for what happens when the Sun changes hydrogen atoms into helium atoms? _______________________ 9. How old is the Sun? ______________________