Aurora Borealis, Acadia National Park, Maine

Photograph by Michael Melford, National Geographic

April 2, 2008

Nature's light show—aurora borealis—bathes Maine's Acadia National Park in a pink glow. These dazzling patterns in nature, called aurora australis in the Southern Hemisphere, are created when charged particles outside the Earth's atmosphere collide with atoms in the upper atmosphere, producing a glowing display of curtains, arcs, and bands stretching across the sky.

Photograph shot on assignment for, but not published in, the November 2005 feature story "Autumn in Acadia National Park."