1. Auroras Matt Tanaka & Kristel Curameng

2. What is an Aurora?  A natural light display in the sky caused by the collision of charged particles directed by the Earth's magnetic field  Its an atmospheric phenomenon typically observed in the night sky from locations at high latitudes.  Commonly known as the, “Northern Light”  A natural light display in the sky caused by the collision of charged particles directed by the Earth's magnetic field  Its an atmospheric phenomenon typically observed in the night sky from locations at high latitudes.  Commonly known as the, “Northern Light”

3. 3 Location  Surrounding the north magnetic pole is the aurora borealis.  Surrounding the south magnetic pole is the aurora australis.  Surrounding the north magnetic pole is the aurora borealis.  Surrounding the south magnetic pole is the aurora australis.

4. What Causes Auroras  Aurora’s occur when highly charged electrons from solar wind interact with elements in the Earth’s atmosphere.

5. 5 Causes continued...  Solar winds stream away at almost 1 million miles per hour.  When they reach the earth they follow the lines of magnetic force generated by the earths core and flow through the magnetosphere.  The magnetosphere is an area of highly charged electrical and magnetic fields.  Solar winds stream away at almost 1 million miles per hour.  When they reach the earth they follow the lines of magnetic force generated by the earths core and flow through the magnetosphere.  The magnetosphere is an area of highly charged electrical and magnetic fields. 5

6. 66 http://www.youtube.com/watch?v=ivBaLt6kj 04&feature=player_embedded

7. 7 Causes continued....  As these charged electrons enter the earths upper atmosphere, they will encounter atoms of oxygen and nitrogen from altitudes from 20-200 miles above earths surface.  The color of the aurora depends on which atom is struck and the altitude it is struck at.  As these charged electrons enter the earths upper atmosphere, they will encounter atoms of oxygen and nitrogen from altitudes from 20-200 miles above earths surface.  The color of the aurora depends on which atom is struck and the altitude it is struck at. 7

8. 8 Green  Oxygen, up to 150 miles in altitude. 8

9. 9 Red  Oxygen, above 150 miles in altitude. 9

10. 10 Blue  Nitrogen, up to 60 miles in altitude. 10

11. 11 Purple/Violet  Nitrogen, above 60 miles in altitude. 11

12. 3 Dominant Forms of Display  First Form  homogenous band or arc of light rises across the lower part of the sky from east to west, reaching within a few degrees of the horizon.  This band may be just 100 m thick.  First Form  homogenous band or arc of light rises across the lower part of the sky from east to west, reaching within a few degrees of the horizon.  This band may be just 100 m thick.

13. 3 Dominant Forms of Display (continued)  Second Form  rays stream up vertically from the arc or band like fringes on fine fabric, following the lines of the Earth’s magnetic field.  Second Form  rays stream up vertically from the arc or band like fringes on fine fabric, following the lines of the Earth’s magnetic field.

14. 3 Dominant Forms of Display (continued)  Third Form  the corona, is seen when the aurora is directly above you, and rays seem to fall around you from the zenith of the sky.  Third Form  the corona, is seen when the aurora is directly above you, and rays seem to fall around you from the zenith of the sky.

15. 15 Works Cited  "HowStuffWorks "How Does the Aurora Borealis (the Northern Lights) Work?"" Howstuffworks "Science" Web. 10 Mar. 2011..http://science.howstuffworks.com/nature/climat e-weather/atmospheric/question471.htm  "Northern Lights - Aurora Borealis." Fairbanks Alaska Visitor Information Site. Web. 10 Mar. 2011..http://fairbanks-alaska.com/northern-lights- alaska.htm  "Auroras: What Makes Them Happen?" Exploratorium: the Museum of Science, Art and Human Perception. Web. 10 Mar. 2011..http://www.exploratorium.edu/learning_studio/a uroras/happen.html  "HowStuffWorks "How Does the Aurora Borealis (the Northern Lights) Work?"" Howstuffworks "Science" Web. 10 Mar. 2011..http://science.howstuffworks.com/nature/climat e-weather/atmospheric/question471.htm  "Northern Lights - Aurora Borealis." Fairbanks Alaska Visitor Information Site. Web. 10 Mar. 2011..http://fairbanks-alaska.com/northern-lights- alaska.htm  "Auroras: What Makes Them Happen?" Exploratorium: the Museum of Science, Art and Human Perception. Web. 10 Mar. 2011..http://www.exploratorium.edu/learning_studio/a uroras/happen.html 15