The unusual STEVE auroral arc across the northern sky at Bow Lake, Banff National Park, Alberta on the night of July 16-17, 2018. The more normal green auroral arc is lower across the northern horizon. But STEVE here appears more pink.

alberta aurora banff national park big dipper bow lake northern lights num ti jah steve auroral arc north sky skies sky photography astronomy astronomical astro photography astro photography science nature astro