Star trails and northern lights

The sky was clear last night, and the auroral activity was supposed to be very low. So I left he camera rolling to create a star trail image.

But unexpectedly, a geomagnetic storm rolled in. So I went out to admire the lights for an hour.

This is what the camera captured.

You can watch a time-lapse video of the northern lights I made with the same source images here:

It was an sky-wide spectacle. The video doesn't really do it justice.