Have you every seen the dazzling, dancing lights of the aurora in the night sky? The closer you are to the North or South Pole, the greater your chances of seeing this amazing spectacle. In the Northern Hemisphere, it is called an aurora borealis or the northern lights. In the Southern Hemisphere, it is called an aurora australis or the southern lights.
What Causes the Aurora? Auroras are a natural interaction between the Sun and Earth's atmosphere. Our Sun generates a strong solar wind, which carries about one million tons of extremely hot plasma (electrons, protons, and other particles) away from the Sun every second. Earth's magnetosphere acts like a shield that protects us from most of this constant solar wind, deflecting it around Earth.
During a solar storm, such as a solar flare or coronal mass ejection, a large amount of plasma hurls through space at high speeds as part of the solar wind. When this extra solar energy collides with Earth's magnetosphere, some of the electrically charged particles move down strong magnetic field lines at the North and South Poles and become trapped in Earth's atmosphere. These particles bounce from the North Pole to the South Pole and back again, transferring energy to molecules in Earth's atmosphere as they go. The colorful, glowing lights of the aurora result when these energized molecules release their extra energy. Continue reading from University Corporation for Atmospheric Research
Aurora Tutorial (Space Weather Prediction Center)
Aurora Borealis (Seven Wonders)
Northern Lights (Aurora Borealis): What They Are & How to See Them (Space.com)
Why Do the Northern and Southern Lights Differ? (Scientific American)
Auroras: The Northern and Southern Lights (UCAR)
Aurora Colors: What Causes Them and Why Do They Vary? (Space.com)
Aurora Colors: What Causes Red, Pink, Purple, Green and Yellow Northern Lights? (The Science Times)
Best Places to See the Southern Lights (Smithsonian Magazine)
The 18 Best Places to See the Northern Lights (U.S. News & World Report)
