10 January, 2000

The Northern Goddess of Dawn: Aurora Borealis

Streams of electrons from the sun are constantly bombarding the Earth. Most of these electrons (travelling at a speed of 2 million mph) are deflected by Earth's magnetic field. However, some of the electrons are pulled into the vortex of the magnetic fields at the north and south poles. When these millions of electrons interact with atoms from the earth's atmosphere an "aurora" is formed.

The formation of an aurora can be compared to the way a neon or fluorescent light works. A steady flow of electrons (electricity) enters the Earth's upper atmosphere and charges (ionizes) atoms of nitrogen, oxygen, and other gases there. Interactions between positively and negatively charged atoms cause the release of tiny bits of light. The waves of color that we see result from the billions of light bursts that are emitted by this process. The color of the aurora is dependent upon which gas is being hit with electricity. Nitrogen will result in shades of red and blue, while (more commonly) oxygen will produce greenish hues.

The aurora usually occurs between 50 and 250 miles above Earth's surface. Some parcticularly strong auroral storms, however, can actually reach the surface.

Aurora True or False

Test your own "Northern Lights" with this auroral trivia quiz! Answers will be provided in tomorrow's journal entry. A PRIZE goes to the FIRST response that I receive with the correct answers!! Send your responses to: marjorie.a.porter@snet.net

1. T/F The first person to use the word "aurora" for the Northern Lights was Galileo.

2. T/F A strong aurora can corrode the Alaskan Pipeline.

3. T/F The color of the aurora depends upon which atmospheric gases are being hit with electricity.

4. T/F Auroral displays are related to solar activity.

5. T/F The aurora has been seen as far south as Mexico.

6. T/F Auroral storms have been known to cause power outages.

7. T/F The southern hemisphere also experiences an aurora.

8. T/F Some locations on Earth may experience an auroral display 2/3 of the year.

9. T/F Some people may be able to "hear" the aurora.

10. T/F Many cultures have associated the aurora with omens.

Photo of the Aurora taken by Alaskan artist Dennis Anderson