The "Long Duration M3.2 Class Solar Flare" started at 8:42 a.m. EST Thursday and released the blast headed toward Earth at 630 miles per second, the space agency said.
The Coronal Mass Ejection or CME is expected to arrive at Earth Saturday, bringing with it bright Northern Lights but also the possibility of communications disruptions, USA Today reported.
"Geomagnetic field activity is expected to be at quiet-to-unsettled levels [Friday through Sunday] with a chance for active levels on [Saturday] due to the expected arrival of today's CME," the National Oceanic and Atmospheric Administration's space weather Web site said.
The CME comes as the sun is in the upward swing of its 11-year cycle of solar activity, with more storms expected though 2014.
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