Crowning in the Sky

On the night of 2015 March 17/18 this umbrella of northern lights unfolded over backyards in Vallentuna, Sweden, only 30 kilometers north of Stockholm. A result of the strongest geomagnetic storm of the solar cycle, auroral displays were captured on that night from back and front yards at even lower latitudes. A boon for aurora hunting skywatchers, the space storm began building when a coronal mass ejection, launched by solar activity some two days earlier, struck planet Earth’s magnetosphere.