What is the meaning of red and green lights on a buoy?

The significance of red and green lights on a buoy is primarily to show direction when approaching splits in channels. This system is part of the U.S. Aids to Navigation System, which uses colored buoys to provide vital information to mariners. When approaching a split or fork in a waterway, a red buoy typically indicates that boaters should keep it to their left when traveling upstream, while a green buoy suggests that it should be kept to the right. Together, these colors help ensure safe navigation and prevent collisions by clearly marking the navigable channel for boats.

This visual guidance is crucial for boat operators, especially during low visibility conditions, to maintain awareness of the channel layout and ensure they are following the correct course. The other options, while related to navigation, do not accurately describe the specific purpose of red and green lights on buoys in this context.