6. The Sun

7. Sun Facts
Our sun accounts for 99.8% of ALL the mass in our solar system
Average size star
( ~ 1.3 million Earths could fit inside the sun )
Estimated age 4.6 billion years old
Light takes 8 minutes to reach Earth

8. The Sun’s Structure The sun does not have a solid surface (granules)
It is a giant ball of glowing PLASMA
Mostly Hydrogen and Helium
Small amounts of other elements
Has an atmosphere and an interior

9. The Sun’s Interior The sun’s interior consists of the Core
Radiation Zone
Convection Zone

10. The Core
The core is where the suns energy is produced – it is the inner most layer of the sun
Temperature 27,000,000 °F
Hydrogen atoms join (fuse) together to form Helium
Nuclear fusion can only occur under extremely high temperature and pressure

11. The Radiation Zone The middle layer of the sun’s interior
Region of very tightly packed gas
Energy is transferred here by electromagnetic radiation
Takes energy about 100,000 years to move through

12. The Convection Zone Outermost layer of the sun’s interior
Hot gases rise from bottom of this layer and move up – then cool and move back down
Convection currents

13. The Sun’s Atmosphere Made up of three layers Photosphere Chromosphere
The inner layer of the atmosphere (surface layer)
Means “light” – it is the part of the sun we see
~ 300 miles thick 10,800 ° F
Chromosphere
“color sphere” - ~ 6000 miles thick
Middle layer – 180,000 °F
Corona
The “crown” or outer most layer – 1,800,000 °F
Extends millions of miles into space
Gradually thins and changes into solar wind

15. The Sun’s Corona

16. Features on the Sun Sunspots Cool areas on the photosphere
Show up as dark spots
Number of sunspots vary – follows an 11 year cycle

18. Prominences
A huge, reddish loop of gas that protrudes from the sun’s surface, linking parts of sunspot regions

20. Solar Flares
An explosion of gas from the sun’s surface that occurs when the loops of sunspot regions suddenly connect

21. Solar Wind
A stream of electrically charged particles that forms in the sun’s corona and flows out into space at high speed