The Icelandic Road and Coastal Administration also frequently has to deal with drivers who cause accidents by stopping their cars, without warning, in the middle of the road.
Tourists have flooded the tiny island nation in recent years, since a number of budget airlines began offering cheap trans-Atlantic flights with free stopovers.
Last year, the number of American visitors - just Americans, not including anyone else - was higher than the population of Iceland itself.
They love the thundering waterfalls, boiling geysers, bubbling volcanoes, and rugged landscapes, and they love taking pictures.
Bemused local authorities say there's no simple solution.
"We can never completely bar people from stopping their cars when the idea pops into their head to take a photo, whether that is of a flock of sheep or horses or anything else which captures their attention," bureaucrat Hreinn Haraldsson said in 2015.
In the recent cases involving the northern lights, police sternly warned the offending drivers to either keep their eyes on the road, or to find a safe spot to stop their car so that they could continue to gaze at the sky.