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EXTREME GEOMAGNETIC STORM—NOW! The biggest geomagnetic storm in almost 20 years is underway now. It has reached category G5—an extreme event. Sky watchers with dark skies may be able to see and photograph auroras even at low latitudes. Get away from city lights and look at the sky! Aurora alerts: SMS Text
CME STRIKE SPARKS WIDESPREAD AURORAS: The first of six CMEs hurled toward Earth by giant sunspot AR3664 hit our planet’s magnetic field today. The impact on May 10th at 1645 UT jolted magnetometers around the world and sparked a geomagnetic storm, which is now extreme. More CMEs are following close behind and their arrival could extend the storm into the weekend. Sign up for Space Weather Alerts to receive instant text messages when the CMEs arrive.
The ongoing storm is producing low-latitude auroras in the southern hemisphere. Ken James sends this picture from the Snake Valley Observatory in Victoria, Australia:
“The red, yellow and green colours were easily visible to my naked eye,” says James.
Readers in the USA should note that the southern latitude of Victoria, Australia, 37 degrees, is the same as the northern latitude of central California. That’s how far down auroras could be seen if it were dark instead of daylight in North America.
Why is this storm so severe? Take a look at the solar wind data from NOAA’s DSCOVR spacecraft:
After the CME struck, the speed of the solar wind blowing around our planet abruptly increased to more than 700 km/s. More importantly, south-pointing magnetic fields from the sun washed over the Earth, opening a crack in our planet’s magnetosphere. Solar wind poured through the gap to turbo-charge the storm.