Green clouds captured on September 13, 2020 @ Abisko National Park, Sweden
© Chad BlakleyGreen clouds captured on September 13, 2020 @ Abisko National Park, Sweden
Last night, auroras unexpectedly exploded over Abisko, Sweden. "It was a great display," says Chad Blakley of local tour guide service Lights Over Lapland. "But it wasn't the auroras that caught our eye." It was the clouds.

What happened? A crack opened in Earth's magnetic field. Solar wind poured in to fuel the display. Such cracks form often during weeks around equinoxes--a pheomenon known as the "Russell-McPherron effect." With the autumnal equinox only 1 week away, more green clouds could be in the offing. Stay tuned.