1. The Structure of the Sun
Chapter 29-1
The Structure of the Sun

2. Fire and Sun For years people thought the Sun’s energy came from fire.
Over the last 100 years we have found it’s not really the case.

3. Composition of the Sun Light is broken up into a spectrum.
Spectrograph

5. Using this info:
Determines temperature, pressure, density of gas

6. Can match spectra lines of elements on Earth to those from Sun

7. Elements in the sun Hydrogen and Helium 75% hydrogen 24% helium
1% trace of all other elements

8. Nuclear Fusion
Nuclei of small atoms combine to form more massive atoms
Hydrogen atoms
Releases energy

9. The Final Product The fusion of Hydrogen produces Helium nuclei
Energy that is released causes light and heat

10. Mass into Energy Einstein E=mc2 Energy = mass x speed of light squared
Speed of light = 300,000 km/s

11. Einstein
Using his equation astronomers were able to explain the huge quantities of energy produced by the sun.
600 million tons of hydrogen is changed into helium every second
The suns light reaches earth in 8 minutes

12. Sun’s Interior
Studies of sun’s motion help scientists to hypothesis the structure

13. Core
15,000,000 C
27,000,000 F
No liquid or solid can exist at this temperature
Ionized gas (plasma)
Extreme pressure

14. Pressure and temperature cause atoms to fuse

15. Radiative Zone Energy moves out from the core 2,000,000 – 7,000,000 C
Energy moved by radiation
Electromagnetic waves

16. Convection Zone 2,000,000 C 3,600,000 F Energy moved by convection
Matter
Energy transferred as gases rise and sink

17. Atmosphere
Upper most layers:
Photosphere
Chromosphere
Corona

18. Photosphere “Sphere of Light” Energy in the form of visible light
Sun spots – cooler dark areas

19. Chromosphere
“Color sphere”
Thin layer that glows red

20. Corona “Crown” Ions (charged particle) escape into space
Make up solar wind that flows out into space