Question 1550Navigation General

The correct answer is A) Zn. In the celestial equator system of coordinates, the Zn (Zenith Angle) is not equivalent to the longitude of the Earth system of coordinates. The longitude is an angular measurement east or west of the prime meridian, while the Zn is the angular distance of a celestial body from the observer's zenith, which is the point directly overhead. The other options, B) LHA (Local Hour Angle), C) SHA (Sidereal Hour Angle), and D) t (time), are all equivalent to the longitude in the celestial equator system, as they represent the angular measurement of a celestial body's position relative to the observer's location.