Videographer Chad Blakley shot his November 9 time-lapse sequence from Abisko National Park on the northern edge of Sweden. It was the latest in a series of videos he has shot during an unusually active period.
Blakley, whose company Lights Over Lapland, offers aurora photo expeditions to the park, says he hopes his footage will inspire interest from amateur photographers. He says recent solar flare activity has produced stunning light shows on an almost nightly basis in recent weeks.
Auroras occur when charged particles emitted by the sun during flare activity, reach Earth's atmosphere and collide with its gases. The most common color, green, is produced by a collision of particles with oxygen molecules at an altitude of about 60 miles above Earth. At 200 miles, those molecules produce a rare, red aurora, while nitrogen produces blue lights.
The Sun is approaching the midpoint of its solar cycle, which occurs every ten to 13 years and concludes with the reversal of its magnetic field from north to south and vice versa.
Solar flare activity is expected to remain at relatively high levels until then. According to NASA, the reversal is expected to take place at the end of this year.