April 10, 2022: Earth’s magnetic field was supposed to be quiet on April 10th. Instead a strong (G3-class) geomagnetic storm broke out. At the apex of the disturbance, auroras crossed the Canadian border into multiple northern-tier US states. Ron Risman sends this time-lapse movie from Milton, New Hampshire:

“We don’t get to see the aurora all that often in New Hampshire, but this solar cycle so far has been fantastic,” says Risman. Before the show was over, the lights spread west all the way to Washington state.

What caused the storm? The prime suspect is a “canyon of fire” CME, which hit Earth’s magnetic field on April 8th. The impact was weak and, at first, it seemed to have little effect. Geomagnetic unrest increased on April 9th as Earth passed into the CME’s strongly magnetized wake. The arrival of an unrelated solar wind stream on April 10th tipped conditions into G3-category storming.

more images: from Shayne Smith of Charlevoix, Michigan; from Dirk S. Miller of Rice Lake, Wisconsin; from Rocky Raybell of Keller, Washington; from Christy Turner of Calgary, Alberta; from Thomas McCarty of Fairbanks, Alaska; from Ian Griffin of Hoopers Inlet, Otago Peninsula, New Zealand; from Gunjan Sinha of Saskatoon, SK, Canada