What is the structure of the Sun

1. What is the structure of the Sun Layers of the Sun

2. What are the layers of the Sun? Core, radiation zone, and convection zone. • In which layer does the nuclear fusion occur? The core. • What is nuclear fusion? Hydrogen atoms join to form helium. • How is energy transferred in the radiation zone ? In the form of electromagnetic radiation

3. What happens to the temperature of gases as they reach the top of the convection zone? Their temperature decreases. • What happens to the gases as they become cooler? They sink to the bottom of the convection zone. • What is convection? Transfer of heat by the movement of currents in a fluid (both interim tests, Fall and Winter, had a question about convection) .

4. Where do convection currents in the sun absorb heat? From the radiation zone. • Where do the convections currents carry this heat? Toward the surface of the sun.

5. The sun’s atmosphere • The sun’s atmosphere(just as the Earth’s atmosphere) has layers. • What are the layers of the sun’s atmosphere from innermost to outermost? The photosphere, the chromosphere and the corona. • If you look at a typical image of the sun, which layer can see? The inner layer, the photosphere. • Why are you able to see this layer? The gases are very thick. Thick enough to be visible.

6. At the start and end of a total eclipse a reddish glow is visible just around the photosphere. This glow comes from the middle layer of the sun’s atmosphere ,the chromosphere. Chromo means color so chromosphere means the color sphere. • Students page 124 figure 2

7. The corona: 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(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. • Students page 125 see figure 2 and answer “apply it 1and 2” and assess your understanding 1a, 1b

8. What features can you see on the Sun? • You can see 3 features on the sun’s surface. • A) sunspots: areas of gas on the sun’s surface that are cooler than the gases around them. • B) prominences: huge loops of gas that link different parts of sunspot regions. • C) solar flares: eruptions of gas from the sun into space. • How do solar flares form? They form when prominences connect.

9. Compare and contrast sunspots and prominences: • Both are made of gas. • Sunspots are regions of relatively cool gas that occur in groups. • Prominences are huge loops of gas that often link different parts of sunspot regions. • Cycles of solar activity affect how much energy the sun emits and these changes can affect the climate on Earth • Students see figure 3 page 126 for a visual representation of sunspots and prominences.

10. Solar wind • What part of the sun and the Earth interact to create auroras and magnetic storms? The solar wind interacts with Earth’s magnetic field. • Aurora: a natural light display caused by the collision of energetic charged particles with atoms in the high altitude atmosphere. • Students: page 127 assess your understanding 2a,2b,2c.