slender crescent MoonThe photo above showing the shy smile of a slender Moon was captured at sunset over the lights of Costa da Caparica, Portugal. The Moon was but one percent illuminated by the Sun on this beautiful spring evening.

Most of the time the smile (or horns) presented by a crescent Moon is quite crooked or sometimes even at the side of the face. On occasion, though, a classic Cheshire grin greets us.

When the Sun sets or rises rather abruptly, for the mid latitudes this happens at sunrise in early autumn and at sunset in early spring, the smile is fairly straight because the Moon is following the Sun, which is directly below it. However, when the Sun sets in summer, for example, its descent toward the horizon is decidedly unhurried (more inclined), and consequently the Moon’s smile is noticeably offset.

via epod