A Watch That Tracks the Phases of the Moon

The simple moon phase complication traces its roots as far back as roughly 200 B.C., when early Greek horologists developed a hand-operated calculator that could predict eclipses. Thirteen centuries later, the Chinese scientist Su Song built a 40-foot-tall water-powered astronomical clock tower, and by the early Renaissance, many church congregations could keep track of the lunar path and of the orbits of the known planets (even if they did believe Earth occupied the center of the galaxy). Eventually, the feature appeared in complex German and English grandfather clocks and, in the 20th century, was shrunken down to fit in a wristwatch. Now, as part of its Luminor Due line, the Italian brand Panerai has introduced a celestial timepiece, a slimmer, more formal alternative to its usually muscular, oversize designs. The 38-millimeter Luna, which comes in several versions — including one with a mother-of-pearl dial and a cushion case made from the house’s trademark mix of gold with touches of copper and platinum — features a three-dimensional 24-karat moon set against a starry night sky. Panerai Luminor Due Luna watch, $20,600, panerai.com.