Photo of the Day 57

Sky Disk at Twilight, Germany, 2004

Photograph by Kenneth Garrett

Found buried in a hill in the town of Nebra in 1600 B.C., this 3,600-year-old sky disk reflects cloud-strewn skies in central Germany. The disk, which tracks the sun's movements along the horizon, contains the oldest known depiction of the night sky and may have served as an agricultural and spiritual calendar.

(Photo shot on assignment for, but not published in, "Star Search," January 2004, National Geographic magazine)