analemma

The figure-eight pattern traced by the sun's position in the sky if you record it at the same time of day from the same place over the course of a year. The asymmetric eight is produced by the combination of Earth's axial tilt and its slightly elliptical orbit. An analemma printed on a globe is the key to reading a sundial. Photographing one requires a year of patience — one exposure per week, same clock time, same tripod position — and the result is one of the most beautiful proofs that the Earth moves.