Keeping watch on the northern lights

A red aurora illuminates a UHF antenna for the European Incoherent Scatter Scientific Association northern lights project at a research ­station near Tromso, Norway. — Michal Siarek/The New York Times

THE world’s first permanent northern lights observatory occupies a small stone building atop Mount Halde in Norway.

Built in 1899 by Kristian Birkeland, a physicist and Arctic explorer, the observatory was an eyrie from which scientists of the early 20th century could study the auroras that shimmered and blazed across the Arctic skies at night.