Navigation, Seamanship, and Shiphandling (NSS) – Officer of the Deck (OOD) Phase 2 Practice Exam

The key idea is the moment a celestial body crosses the local meridian—the line running north-south through your position. That crossing is known as the culmination, i.e., the transit of the meridian. In many contexts, these terms are used interchangeably to describe the same event: the body reaches its highest point in the sky as it passes the local meridian. For the Sun, this meridian crossing corresponds to local apparent noon, so you’ll also hear it called the Noon Moment in solar observations. Zenith Passage is a different event entirely, occurring when a body crosses the observer’s zenith, not the meridian. So the term that names the same event, exactly, is meridian transit, which is why that option is correct.