THE SUN

1. Chapter 3, Lesson 2 THE SUN

2. The sun’s interior consists of the core, the radiation zone, and the convection zone. Unlike Earth, the sun does not have a solid surface. Rather it is a big ball of gas made mostly of hydrogen and helium and smaller amounts of other elements. The Sun’s interior

4. The sun produces an enormous amount of energy in its core, or central region. The sun’s energy comes from nuclear fusion. In the process of nuclear fussion, hydrogen atoms join together to form helium. Nuclear fusion only occurs under extreme conditions of extremely high temperatures and pressure. The Core

5. The core

6. The energy produced in the sun’s core moves outward through the middle layer of the sun’s interior, the radiation zone. It is a region of very tightly packed gas where energy is transferred mainly in the form of electromagnetic energy The convection zone is the outermost layer of the sun’s interior. Hot gases rise from the bottom of the convection zone and gradually cool as they approach the top. The Radiation and Convection zone

7. Radiation and convedtion zones

8. The sun’s atmosphere includes the photosphere, the chromosphere and the corona. The sun’s atmosphere

10. The photosphere is the inner layer of the sun’s atmosphere. The Greek word “photos” means light, so photosphere means the sphere that gives off visible light When you look at an image of the sun, you are looking at the photosphere. It is considered to be the sun’s surface layer. The photosphere

11. During a solar eclipse, the moon blocks the light from the photosphere and it no longer produces the glare that keeps you from seeing the sun’s faint, outer layers. The glow that you see during a solar eclipse is from the chromosphere, which is the middle layer of the sun. The Greek word “chroma” means color. So the chromosphere is the color sphere. The chromosphere

12. During a total solar eclipse an even fainter layer of the sun becomes visible. This outer layer, which looks like a white halo around the sun, is called the corona. Corona means “crown” in Latin. The corona extends into space for millions of kilometers. It gradually thins into streams of electrically charged particles called the solar wind. The corona

13. Features on or just above the sun’s surface include sunspots, prominences and solar flares. Sunspots are areas of gas on the sun’s surface that are cooler than the gases around the, Sunspots usually occur in groups. Huge reddish loops of gas called prominences often link different parts of sunspot regions. Solar flares are gas eruptions that take place out into space when the energy of the sun heats the gases. Features on the sun

14. Solar wind particles can also affect Earth’s magnetic field causing magnetic storms. Magnetic storms sometimes disrupt radio, telephone, and television signals and also cause electrical power problems. Solar WInd

15. SUN’S FEATURES