Final answer:
Marine navigation lights are critical for vessel safety and include a white light on the ship's centerline, red and green sidelights with a specific arc of visibility, a white stern light, a yellow light indicating towing, and flashing lights at navigational aids or lighthouses.
Step-by-step explanation:
The characteristics of lights used in marine navigation are specifically designed to ensure the safety of vessels at sea by providing important information about their orientation and motion. The lights follow international regulations known as the International Regulations for Preventing Collisions at Sea (COLREGs). Each light serves a distinct purpose:
- A white light is placed over the fore and aft centerline of the ship, shining in a 225-degree arc, which allows the ship to be seen from the front and sides.
- Red and green sidelights are located on the port and starboard sides of the vessel respectively, each covering a 112.5-degree arc, with a 3-degree overlap to ensure no blind spots.
- A white light at the stern shows a 135-degree arc, making it visible from behind.
- A yellow light may be used to indicate a towing operation when it is placed above the stern light.
- A light flashing at regular intervals of 120 flashes or more per minute is typically a navigational aid or warning signal, often used in lighthouses to warn ships of dangerous shorelines or obstacles.