🔍 Key Concepts

• Apparent angular size of celestial bodies as seen from Earth • Typical angular diameter of the Sun and Moon used in basic navigation calculations • Relationship between degrees (°), minutes (') and the full circle of 360°

💭 Think About

• First, recall roughly how many degrees across the Sun or Moon appear in the sky. Is it a tiny fraction of a degree, about half a degree, or several degrees? • Think about how many minutes of arc are in one degree and convert a commonly remembered value in degrees for the Sun/Moon into minutes. • Compare each choice with what you might use as the Sun or Moon’s diameter when sketching or working sight-reduction problems.

✅ Before You Answer

• 1 degree = 60 minutes of arc (60') — convert any value in degrees to minutes before comparing • Recall that the Sun and Moon appear almost the same size in the sky, on the order of about half of one degree, not several degrees • Eliminate options that are unrealistically small (much less than a tenth of a degree) or close to a full degree or more