Question 1615Navigation General70% to pass
Concerning a celestial observation, the azimuth angle is measured from the principal vertical circle to the _______________.
AI Explanation
The correct answer is C) vertical circle of the body.
The azimuth angle is measured from the principal vertical circle (a great circle passing through the zenith and the north and south points of the horizon) to the vertical circle of the celestial body being observed. The vertical circle of a celestial body is the great circle passing through the zenith and the celestial body. This is the standard definition of azimuth in celestial navigation.
The other options are incorrect because the azimuth is not measured relative to the local celestial meridian (A), the Greenwich celestial meridian (B), or the hour circle of the body (D). Those are different reference circles used in celestial navigation, but not the one used to define azimuth.
Related Questions
#1613 Given are the courses and speeds of 4 vessels. The navigator of which vessel would be required to know the actual time of meridian transit in order to take an accurate observation at LAN? #1614 In which of the following does the arc of a great circle pass through a body and the celestial poles? #1616 The Sun's center is coincident with the principal vertical circle when _______________.#1617 The owner or Master of a towing vessel shall ensure that each person that directs and controls the movement of the vessel can accomplish all of the following EXCEPT _______________.#1618 When the time is based on the movement of the visible Sun along the ecliptic the time is known as _______________.