Question 1396Navigation General

The correct answer is B) directly over the observer. The zenith is the point on the celestial sphere that is directly overhead the observer's location. It is the point on the celestial sphere that is 90 degrees directly above the observer's head. This is because the celestial sphere is a hypothetical sphere surrounding the Earth, with the observer at the center. The zenith is the point on this sphere that is directly over the observer. The other answer choices are incorrect because: A) Greenwich is a location on Earth, not a point on the celestial sphere; C) the eastern horizon is a different point on the celestial sphere; and D) 90 degrees away from the poles would not be directly overhead the observer.