Aurora Borealis. An unforgettable sight from an unforgettable location. If you've seen the Northern Lights you already know it's an experience you'll never forget. Aurora Borealis pictures in books just can't capture its enormity, beauty or emotional impact. If you haven't, make sure your first time is as spectacular and clear as possible in Northern Maine, away from city lights and sounds. Up here, it's just you and the sky putting on a breathtaking show of glowing arcs with curtains of pink, green, yellow and violet light, all building to a climax. Plan a Maine vacation for late summer or fall and take advantage of some great opportunities for viewing this natural phenomenon, with dark clear skies. Both amateurs and professional photographers can get fantastic photos of the Northern Lights. As solar wind interacts with the Earth's magnetic field, some of the particles are trapped by it and follow the lines of magnetic force down into the ionosphere, the section of the Earth's atmosphere that extends from about 60 to 600 kilometers above the Earth's surface. When the particles collide with the gases in the ionosphere they start to glow, producing the spectacle that we know as the auroras, northern and southern. Photo 1999, Bill Plackson