Moonraker (sail)

A moonraker, also known as a moonsail, is a square sail set above a skysail on a sailing ship. It is the highest sail on a full-rigged ship or other square-rigged vessel when all sails are set. Moonrakers are relatively small sails, and their primary purpose is to catch the lightest of breezes and increase the vessel's speed in calm conditions. Due to their height and the difficulty in handling them, moonrakers were rarely used except in fair weather and were considered something of a vanity sail, displaying a ship's ability to carry a large amount of canvas. Above the moonraker, a further sail, a "hopeful," could sometimes be flown, although this was exceptionally rare.