🔍 Key Concepts

• Double star (binary or optical) definition in maritime/astronomical navigation • Difference between physical properties (brightness, declination) and appearance in the sky • How stars are plotted and identified on a nautical star chart

💭 Think About

• Look at which choices describe how the star LOOKS in the sky versus how bright it is or where it is located • Ask yourself: when using a star finder or star chart, what would make a star specifically labeled as a "double star"? • Consider whether "double" is referring to number of stars, brightness, or position on the celestial sphere

✅ Before You Answer

• Verify which option talks about two stars in relation to each other • Eliminate any answers that only talk about brightness changes without mentioning two stars • Eliminate any answers that involve declination relationships to the Sun, since that is not part of the basic definition of a double star