On the tour, we’re told the best time to see the Aurora is in the winter months, when the long, dark polar nights prevail. From late November through to mid-January, the sun doesn’t rise in Tromsø at all, while the summer gifts the city with days where the sun stays just above the horizon for 24 hours. I watch as sections of the day are lit in a dreamlike wash of deep blue and violet, before giving way to complete nightfall, courtesy of my December trip.