CNN  —  It tracks the sun’s position in the sky. It chimes with the sound of hammers hitting four miniature gongs. It even tells the wearer when certain stars will be visible from Earth. Swiss watchmaker Vacheron Constantin’s latest timepiece is not just packed with novel features — it is, officially, the most complicated mechanical wristwatch ever produced. In horology , a “complication” refers to any function that goes beyond standard time-telling, such as a Gregorian calendar or moon phase