What do the red, green, and white lights indicate when seen together at night?

The combination of red, green, and white lights observed together at night typically indicates the presence of another vessel's stern. In maritime navigation, boat lighting is standardized to help operators identify the direction and type of other vessels.

The green light is located on the starboard (right) side of a boat, while the red light is on the port (left) side, and a white light is generally found at the stern. When you see a red, green, and white light together, this configuration suggests you are seeing the back of another boat, as you will observe the white stern light along with both colored sidelights. Understanding these light configurations is essential for nighttime navigation and helps in assessing the relative position and heading of approaching vessels, promoting safe boating practices.