What creates the different colors?


The colors of the aurora can be green, yellow, pink, blue, violet and red

The colors of the aurora depend on the atmospheric gases that the solar winds encounter as well as the altitude in which they interact. 

Oxygen and nitrogen are the most abundant gases in the atmosphere and create most of the colors that we see. The green lights are the most common.  Oxygen creates the green lights when the solar winds interact with the air molecules below 240 km (approx. 150 miles) in altitude. 

Nitrogen creates the blue lights when the altitude is below 100 km (approx. 62 miles), but above this altitude nitrogen will emit a purple or violet color. 


The image below shows atoms being excited at different altitudes.



 



The red aurora is one of the rarest phenomenons.   This aberration is the result of the solar winds interacting with oxygen at altitudes above 240 km.

Red Aurora

Red aurora borealis over Wrangell/St.Elias National Park in Alaska.
             Michael S. Quinton/National Geographic/­Getty Images.





The following image is the light spectra of  oxygen and nitrogen and shows the wavelength in nano-meters. 





Oxygen



Nitrogen



The aurora can depict wisps, pillars, pinwheels, arcs, rays, curtains, ribbons and halos of dancing lights. The dancing of the aurora is created by the movement of the lights with the atmospheric currents.             

Pink Aurorada
Aurora Borealis as seen in Michigan                                                             Aurora Borealis as seen from Delta Junction Alaska on April 10, 2015






The heavens declare the glory of God; The skies proclaim the work of His hands.
Day after day they pour forth speech; night after night they reveal knowledge.
They have no speech; they use no words; no sound is heard from them.
Yet their voice goes out into all the earth, their word to the ends of the world.
In the heavens God has pitched a tent for the sun.

Psalm 19:1-4 NIV


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Background Photo ©2014 Casey Bullmer taken in Fairbanks, Alaska.