1. Cycle of Solar Activity
The Sun
Cycle of Solar Activity

2. The Sun
sohowww.nascom.nasa.gov

3. Sun’s Energy Due to nuclear fusion
Hydrogen atoms combine to form helium – this gives off energy (light and heat)
Happens in the core

4. Sun’s Atmosphere Inner Atmosphere: Photosphere Gives off visible light
considered the sun’s surface
What you see when you see the sun

5. Sun’s Atmosphere Middle Atmosphere: Chromosphere
Reddish in color (color sphere)
folk.uio.no

6. Sun’s Atmosphere Outer Atmosphere: Corona
Can see during a total eclipse (means crown)

7. Sun’s Atmosphere
Can not normally see outer two atmospheres because of the glare from the photosphere
Only see during solar eclipses
See chromosphere at beginning and end of eclipse and corona at total eclipse

8. Solar Wind
Flow of electrical charged particles from the sun’s corona (can travel 900 km/sec!)
When interact with atoms of gas in Earth’s atmosphere cause auroras
apod.nasa.gov

9. Sunspots – areas of cooler gas on the sun

10. Sunspots
"SOHO (ESA & NASA)"

11. Solar Prominence – loops of gas that connect sunspot regions

12. Erupting Prominence 2001

13. Eruptive Prominance 1999

14. Twisting Prominence 2000

15. Arching Prominence

16. Solar Flares – explosive releases of energy due to prominences connecting

17. Solar Flare

18. Coronal Mass Ejection (CME) 2007

19. Another CME 2000

20. CME
"SOHO (ESA & NASA)"

21. CME April 25, 2003

22. Why Sunspots are Darker
Sunspots are areas of cooler gas – which give off less light – so look darker /
misterzwanch.com/NASA/sunspot.gif.bmp

23. Number of Sunspots Varies over a period of 10-11 years
Hypothesis: cycle may influence short term climate changes on Earth (sun gives off different amount of energy)
science.nasa.gov

24. Radiation Zone Middle layer of sun’s interior
Has very tightly packed gas
Energy transferred here through electromagnetic radiation.
Energy takes 100,000 years to travel through here
members.rediff.com

25. Convection Zone Outer layer of the sun’s interior
Hot gas rises up, cools as it rises, and then sinks back down forming loops of gas
These loops move energy towards the sun’s surface
members.rediff.com

26. June 2, 1613

27. June 3, 1613

28. June 5, 1613

29. June 6, 1613
The Galileo Project

30. June 7, 1613

31. June 8, 1613

32. June 9, 1613

33. June 10, 1613

34. June 11, 1613

35. June 12, 1613

36. June 13, 1613

37. June 14, 1613

38. What did you notice in Galileo’s Drawings?
The Solar Center Stanford University

39. Sunspot Movement from SOHO
"SOHO (ESA & NASA)"
Solar Center Stanford University

40. Solar Center Stanford University
The sun rotates!
The sun rotates once every 27 days
Different parts of the sun rotate at different speeds
Solar Center Stanford University

41. Sun pictures are from: sohowww.nascom.nasa.gov/ Gallery of Images

42. Works Cited
Many images Courtesy of SOHO/[instrument] consortium. SOHO is a project of international cooperation between ESA and NASA.
The SOLAR Center at Stanford University
The Galileo Project at Rice University
NASA