According to Halverson,
It is the result of 20-30 second exposures edited together over many hours to produce the timelapse. This allows you to see the Milky Way, Aurora and other phenomena, in ways you wouldn’t normally see them.
You can click on the video below to watch it. Be sure to play it in full screen mode and turn up your sound. The music was written by Bear McCreary, who also wrote the stunning music for the Sci-Fi channel’s much-acclaimed remake of “Battlestar Galactica,” my favorite science fiction TV series. Watching this brought back fond memories of many nights spent looking through my telescopes under the amazingly dark skies of the eastern Montana prairie. Enjoy.