1. The Solar Surface Luminosity Luminosity Sunspots Sunspots Sunspot Cycle Sunspot Cycle Solar Prominences Solar Prominences Differential Rotation Differential Rotation Solar Wind Solar Wind Auroras Auroras

2. So How Much Energy Does the Sun Release? Luminosity = the total power output of the Sun Luminosity = the total power output of the Sun 1 second of the Sun’s energy = 500,000 years of energy for us! 1 second of the Sun’s energy = 500,000 years of energy for us! 3.8 x 10 26 watts 3.8 x 10 26 watts 380,000,000,000,000,000,000,000,000 watts! 380,000,000,000,000,000,000,000,000 watts! That’s 380 septillion watts That’s 380 septillion watts That’s 3,800,000,000,000,000,000,000,000 100 watt light bulbs! That’s 3,800,000,000,000,000,000,000,000 100 watt light bulbs! 3.8 sextillion light bulbs 3.8 sextillion light bulbs $0.65/hr $4,111,599,999,920,000,000,000,000 hour $6,852,666,666,540,000,000,000.00 per minute $114,211,111,109,000,000,000 per second $0.65/hr $4,111,599,999,920,000,000,000,000 hour $6,852,666,666,540,000,000,000.00 per minute $114,211,111,109,000,000,000 per second

3. Magnetic field – flow of electromagnetic energy Sunspots = Darker and cooler areas on the Sun. Caused by a concentration of the Sun's magnetic field, which last from several hours to several months. Usually occur in pairs Light and dark in this magnetic scan of the Sun indicate concentrated areas of intense magnetic fields. Magnetism and Sunspots

4. Solar Prominences They are eruptions caused by the flow of electromagnetic energy from sunspot to sunspot. They are eruptions caused by the flow of electromagnetic energy from sunspot to sunspot. Cooler gases above the photosphere can often be seen flowing along magnetic field lines. Cooler gases above the photosphere can often be seen flowing along magnetic field lines. A fairly common occurrence A fairly common occurrence

6. Large Solar Prominences This is the largest prominence observed. This huge prominence is 100,000 kilometers above the Sun. 28 Earths high

7. Solar Flare An eruption of energy An eruption of energy Does not “jump” from sunspot to sunspot like a prominence Does not “jump” from sunspot to sunspot like a prominence

8. Sunspot Cycle – Rising and falling levels in the number of observable sunspots. Solar maximum – numerous observable sunspots Solar minimum – only a few sunspots are visible Has a period of about 11 years Sunspots migrate Mid-latitudes to equator Why?

9. What Causes the Sunspot Cycle and Migration? Not well understood! Not well understood! May be related to convection currents May be related to convection currents As the convection cells rise and fall they may be dragging pockets electromagnetic energy up with them. As the convection cells rise and fall they may be dragging pockets electromagnetic energy up with them. Differential Rotation Differential Rotation Period of 27 days at equator, 31 days at poles Period of 27 days at equator, 31 days at poles May stretch and distort magnetic fields May stretch and distort magnetic fields

10. The Solar Wind A constant stream of particles that flow from the Sun’s corona, with a temperature of about a million degrees and with a velocity of up to 450 kilometers per second. The solar wind reaches out beyond Pluto's orbit (about 5900 million kilometers).

11. Auroras They are also called Northern or Southern lights. These often brilliant and colorful phenomena, seen in the night sky usually closer to the poles. They are caused by the impact of solar wind particles and magnetic forces on the Earth’s magnetosphere.

12. How is the Solar Interior Observed? Prediction Models Prediction Models Computer Analysis and Simulations Computer Analysis and Simulations Sun Quakes Sun Quakes Vibrations of the Sun Vibrations of the Sun Releasing pressure Releasing pressure Helioseismology Helioseismology Doppler Radar Doppler Radar Neutrinos Neutrinos Neutrinos – neutral particles released during fusion Neutrinos – neutral particles released during fusion Rarely interact with anything Rarely interact with anything Neutrino Problem! Neutrino Problem!