Northern lights delight as 'cannibal' solar storm triggers auroras across US and Canada (photos)

Northern lights appearing as a vibrant green ribbon of light in the sky. .

Over two days the sun launched a barrage of coronal mass ejections (CMEs) — expulsions of plasma and magnetic field — toward Earth. 

The first two CMEs combined and formed a "cannibal CME" which hit on July 29 at 8:27 p.m. EDT (0027 on July 30), sparking a minor G1-class geomagnetic storm and triggering northern lights across the U.S. and Canada.