2. Sun vs. Earth Sun as wide as 109 Earths. Sun’s volume is 1.25 million times greater. Sun has 332,000 times more mass. Sun has only ¼ the density.

8. Sun’s Layers Photosphere –Photos = light Sphere = ball –Visible “surface” made of gas –Has small, bright markings called granules –Granules make the surface appear to boil

9. Sun’s Layers Chromosphere –First layer of Sun’s “atmosphere” –Can only be seen during a total solar eclipse or by blocking out the light from the photosphere –A few thousand kilometers thick

10. Sun’s Layers Corona –Means “crown” –Outermost layer of Sun’s “atmosphere” –Only visible when photosphere is covered –Very weak, about half the brightness of a full moon –Extends a million kilometers from Sun

11. Active Sun Sun is very active The Sun’s equator rotates faster (25 days) then areas near the top and bottom (33 days) Sunspots, prominences, and solar flares are proof of activity

12. Active Sun Sunspots –Dark areas on the Sun’s surface that are 1500k cooler then the surrounding surface

15. Active Sun Prominences –Huge cloudlike structures made of gas that explode from the Sun’s surface at 1000 kilometers per second

17. Active Sun Solar Flares –Brief outbursts where enormous amounts of energy are released

21. The Solar Interior Nuclear Fusion Energy = (mass X speed of light)2 or E=mc2 –Speed of light = 300,000km/s –Because the speed of light is so large, a small amount of hydrogen converted into Helium creates an enormous amount of energy –Converting the amount of hydrogen that could fit on the head of a pin into Helium releases more energy then burning thousands of tons of coal