Lapland Aurora Cam — Posio, Finland

This live camera looks north over Posio in Finnish Lapland, roughly 100 miles inside the Arctic Circle — one of the most reliable places on Earth to watch the aurora borealis. From late August through early April, when the polar night deepens and the skies go dark, the northern lights ripple overhead in curtains of green, and on strong geomagnetic nights, violet and crimson. Posio sits in a low-light-pollution belt of lakes and old-growth spruce forest, which is exactly why aurora hunters and photographers favor it. The aurora is driven by solar wind striking the upper atmosphere, so activity rises and falls with the Sun's 11-year cycle and with day-to-day space weather. Check the Kp index before you watch — a Kp of 3 or higher over Lapland usually means a good show. Peak viewing runs from about 9 PM to 2 AM local time on clear nights, with the deepest darkness around the winter solstice. In summer, the same camera shows the opposite extreme: the midnight sun, when the Sun barely dips below the horizon and the forest glows through the small hours. Posio is also known for Korouoma Canyon and its frozen waterfalls, Riisitunturi National Park's snow-laden "crown snow-load" trees, and a deep Finnish ceramics tradition.