Week 13 at the Pole

ICLpretty
Martin Wolf, IceCube/NSF

The sun has set, they’ve held their traditional sunset dinner, and yet … it’s still light outside. Well, that’s twilight. Even after the sun falls below the horizon, the scattering of light in the upper atmosphere illuminates the lower atmosphere and the Earth’s surface. At the South Pole, the initial period of twilight—or