🔍 Key Concepts

• Aids to Navigation (ATON) publications used in U.S. waters • Where detailed light characteristics (color, period, phase, range) are officially listed • Difference between planning references and operational navigation references

💭 Think About

• Which publication is specifically compiled by the U.S. Coast Guard to list all lights, buoys, and daybeacons in a region? • Which references are mainly for route planning, coastal descriptions, and general navigation theory rather than raw light data? • If you needed the exact occulting/flashing pattern, height, and nominal range of a lighthouse, which book would you reach for on the chart table?

✅ Before You Answer

• Identify which choice is a USCG-maintained directory of lights and other aids to navigation • Eliminate any publication that is mainly for sailing directions, harbor descriptions, or navigation theory • Confirm that the correct reference gives precise light characteristics like period, color, and type of flashing for each aid