A potent solar flare has unleashed the biggest radiation storm since 2005 and could disrupt some satellite communications in the polar regions, US space weather monitors said Monday. The event started late Sunday with a moderate-sized solar flare that erupted right near the center of the Sun, said Doug Biesecker, a physicist with the National Oceanic and Atmospheric Administration Space Weather Prediction Center. "The flare itself was nothing spectacular, but it sent off a very fast coronal mass ejection traveling four million miles per hour (6.4 million kilometers per hour)," he told AFP.

Night-sky viewers in Asia and Europe may be able to witness the aurora, or Northern Lights, late Tuesday as a result of the storm.