1. STARS Space Science Lab 2008

3. ElementPercent of Total Mass Hydrogen71.0 Helium27.1 Oxygen0.97 Carbon0.40 Nitrogen0.096 Silicon0.099 Magnesium0.076 Neon0.058 Iron0.014 Sulfur0.040 Composition of a Star Like the Sun

4. How does the sun produce energy in its center? 1.Through chemical burning of hydrogen (2 H + O → H 2 O). 2.Through thermonuclear fusion of helium into Carbon. 3.Through thermonuclear fusion of hydrogen into helium. 4.Through thermonuclear fission of helium into hydrogen. 5.Through thermonuclear fission of Uranium into lighter nuclei.

5. Structure of a Star Temperature, pressure and density increases Energy generation via nuclear fusion Energy transport via radiation Energy transport via convection Flow of energy Star

7. What would happen if the sun suddenly stopped producing energy in its center? 1.It would explode. 2.It would rapidly collapse. 3.It would gradually cool off and shrink. 4.It would gradually cool off and expand. 5.It would maintain its current structure.