Chart Navigation & Plotting · Sailings — Great Circle on a Mercator
On a Mercator chart, a great-circle track between two points in the Northern Hemisphere appears as:
- AA circle
- BA straight line
- CA curve bowed toward the equator
- DA curve bowed toward the nearer pole (concave toward the equator)✓ Correct
Explanation
Because the Mercator projection stretches the higher latitudes, a great circle plots as a curve bowing poleward (toward the nearer pole, concave toward the equator). A rhumb line, by contrast, plots as a straight line on a Mercator chart.
Authority: Bowditch (Pub. No. 9), Chart Projections
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