"St. Patrick's Aurora"

Geomagnetic Storms
Sometimes during the solar magnetic events, solar explosions hurl clouds of magnetized particles into space. Traveling more than a million miles per hour, these coronal mass ejections, or CMEs, made up of hot material called plasma take up to three days to reach Earth. Spacecraft and satellites in the path of CMEs can experience glitches as these plasma clouds pass by. In near-Earth space, magnetic reconnection incites explosions of energy driving charged solar particles to collide with atoms in Earth’s upper atmosphere. We see these collisions near Earth’s polar regions as the aurora.

The prevalence of specific gases in the atmosphere determines the color of the aurora. For example, if charged particles strike oxygen atoms, the aurora will appear green. Excited nitrogen closer to 60 miles above Earth’s surface will produce a blood red color. Three spacecraft from NASA’s Time History of Events and Macroscale Interactions during Substorms (THEMIS) mission, observe these outbursts known as substorms. Substorms can intensify aurora’s near Earth’s poles.

To learn more about the aurora, go to NASA’s THEMIS mission: www.nasa.gov/mission_pages/themis/main/index.html

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Original caption:
How about a little something green for St. Patrick's Day?

"St. Patrick's Aurora" was taken at Donnelly Creek, Alaska at 1:30 am, March 17, 2015 by our good friend Sebastian Saarloos!

You can see more images from Sebastian here: www.facebook.com/SebastianSaarloos

Credit: Sebastian Saarloos

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