Solar flares expand aurora borealis shows visible from North America
WASHINGTON, September 12, 2014 — Two recent solar events have led the Space Weather Prediction Center to issue a strong geomagnetic storm watch for this weekend, Friday and Saturday night.
The sun is a giant ball of superheated gas (plasma) made of 92.1% hydrogen and 7.8% helium, and like any gas bag, it sometimes bloats and expels a bit of matter. In the sun’s case, that burst is called a “coronal mass ejection,” or CME. These are the most explosive events in the solar system.
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This week, the sun produced two ejections, on September 9 and 10. These sent clouds of fast-moving charged particles shooting out of the sun’s outer atmosphere. CMEs are linked to solar flares. The second CME this week was produced from a flair which NASA says was an X1.6 class, putting it in the most intense category.
Because of the sun’s distance from earth — about 93 million miles — those charged particles are just hitting our magnetosphere and atmosphere, where they may produce a spectacular reaction to the solar flair actions.
NASA and Space Weather experts are both guessing at that this solar storm will do.
When charged particles hit our upper atmosphere, they strip electrons from oxygen and nitrogen molecules. Just as in a neon light, this produces colored light, in this case green and red — the aurora borealis, or northern lights. For persons in the higher northern areas, there should be stronger aurora borealis light shows than usual, with stronger colors across the spectrum. The aurora may be visible as far south as the central U.S.
When the charged particles of a CME hit the magnetosphere, they may have another less desirable affect; they can cause a geomagnetic storm, with enormous electrical currents in the magnetosphere inducing huge currents in long-distance power lines. The result can be small or extensive disruptions of the power grid. They could knock out power here on earth, or interfere with GPS and radio communications. This includes those on commercial airliners.
There could also be damage to satellites.
“People on the ground really don’t have to worry,” said Lika Guhathakurta, a program scientist with NASA’s Solar Dynamics Observatory.
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Solar storms don’t usually affect humans on the ground, but they can cause trouble for astronauts and sensitive electrical equipment. NASA is taking steps to keep the crew members on the International Space Station safe.
Satellite operators are being counseled to turn off sensitive sensors on satellites.
Disruptions, short of a complete power loss, should be minimal; we should not lose our basic services like cell phones, according to Dr. Petrus Martens, an expert on solar flares and a professor in the Department of Physics and Astronomy at Georgia State University.
Dr. Martens has said that we might expect:
• Distortions in GPS readings of up to a few yards which would effect military applications, such as drones, much more than your travels.
• Increased corrosion of long pipelines like the Alaska oil pipeline.
• Homing pigeons going off course. (Just when it would be fun to have homing pigeons!)
This is not the first solar storm to affect the earth. On March 13, 1989, Quebec lost power for 12 hours. While power grids in the United States were affected, there are no records of any blackouts due to CME.
NASA reports that during the Quebec blackout, some satellites tumbled out of control; the orbiting space shuttle Discovery had a mysterious sensor problem that went away after the storm, according to NASA
Tonight and over the weekend, aurora watchers in the northern United States who are outside major metropolitan areas should be watching the skies.
“A fantastic display of Northern Lights as far south as the northern half of the U.S.” is possible, Martens said.
The current solar eruptions are benign by comparison — though the fact that there are two of them in such close proximity is unusual.
Here’s a video of the X-class solar flare-up on September 10, courtesy of NASA: