“…During the shortening nights of April in Alaska, the soft glow of twilight remains long after the sun has set, giving the northern latitudes ever-lengthening two-hour shades of blue after sunset and before sunrise .  Soon these twilights meet together and dispense with any darkness altogether.  On rare occasions, during the deepest part of astronomical twilight when stars appear, there is a brief window to space that can allow auroral displays to appear if they occur.  Here, at the fringe of night and twilight, a violet-edged auroral corona crosses at zenith, the center of night, lending its sparkling dance to the moon …”