Unprecedented solar activity could light up US skies, disrupt power and communications

The most powerful solar storm in more than two decades struck Earth on Friday, triggering spectacular celestial light shows in skies from Tasmania to Britain -- and threatening possible disruptions to satellites and power grids as it persists into the weekend. The first of several coronal mass ejections (CMEs) -- expulsions of plasma and magnetic fields from the Sun -- came just after 1600 GMT, according to the National Oceanic and Atmospheric Administration (NOAA)'s Space Weather Prediction Center.